Article: 225030 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4485eeaa$0$3704$ecde5a14@news.coretel.net> Message-ID: Date: Wed, 07 Jun 2006 03:30:30 GMT clfe wrote: > DUH - I KNOW THAT - I was just saying the tapping let the people at the > surface know there were 9 people down there. MORSE CODE - "could" have > relayed much more info if one of them knew it. REREAD my message....... How do you send a 'dash' by tapping on a pipe? You apparently could revolutionize prison communications by providing an answer to that simple question. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225031 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: sealing coax holes in outside wall Message-ID: Date: Tue, 6 Jun 2006 20:36:46 -0700 "Chris W" <1qazse4@cox.net> wrote in message news:fy7hg.52579$9c6.12825@dukeread11... > Can anyone tell me what the official name of the putty they use to seal > the holes you run your coax through so bugs don't crawl in the wall or > water doesn't get in? I like to get all my hardware type items from > mcmaster.com. I'm sure they have it, if I just know what it is called I > can find it on their website. I was thinking "electrician's putty" or similar -- what we used to call "monkey shit" in the Navy, but I couldn't get a good match on Google for those terms. While mulling this over, I remembered also Plumbers Putty. While generally not used for coax, I have used it under sinks and in the garage for sealing around pipe penetrations. What I have is light tan in color. It stays soft and flexible (but I don't know what sunlight does to it or whether it will take paint). It's cheap and available and might be just what you need. Article: 225032 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: FIGHT! FIGHT! FIGHT! References: <1149609129.041873.312040@g10g2000cwb.googlegroups.com> <23774-44862470-817@storefull-3257.bay.webtv.net> Message-ID: Date: Wed, 07 Jun 2006 03:38:07 GMT Richard Harrison wrote: > (mx) is a straight line. Every value of (b) produces a straight lline > parallel with lhe line y=mx when b=0. Factor (b) is merely the offset > value of the sloped line in the x direction. Why must superposition preserve 'b' (as someone has asserted?) -- 73, Cecil http://www.qsl.net/w5dxp Article: 225033 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <448624c0$0$6154$39cecf19@news.twtelecom.net> <448628bb$0$3693$ecde5a14@news.coretel.net> Message-ID: Date: Wed, 07 Jun 2006 03:41:05 GMT clfe wrote: > I'm not sure if you're referring to my post or someone else's who I didn't > see. In "my" example - I was saying if a MIC was broken and they knew code, > they could short out the tranmit pins - like making and breaking contact > such as a key would do - to broadcast a coded message. It "can" be done. Please tell us when, in human history, it has ever been done. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225034 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <1148272981_5573@sp6iad.superfeed.net> Subject: Re: Grounding a metal roof Message-ID: Date: Tue, 6 Jun 2006 20:54:08 -0700 "Steve N." wrote in message news:e64jaq$mml$1@avnika.corp.mot.com... < snip > > Do you know about the web site? > http://www.usncva.org/ > didn't see any recognizable names there. > > 73, Steve, K9DCI I remember the typewriter shop at the receiver building. First door on the right, inside the front door. I never worked there, but I often fetched a shelf spare for an operator. I know about the NCVA, but I've never been to the website. Going now. TKS 73 John KD6VKW Article: 225035 of rec.radio.amateur.antenna Message-ID: <4486538A.5070005@fuse.net> Date: Wed, 07 Jun 2006 00:18:18 -0400 From: jawod Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> Cecil Moore wrote: > clfe wrote: > >> Many of you may have heard of the Quecreek Mine incident in PA some >> time ago. A pipe was drilled down into the shaft. Those at the surface >> heard 9 taps on it, signifying there were 9 miners there. NOW - if any >> of those miners KNEW code, they could have gotten a message to the >> surface as to what conditions were exactly, the extent of injuries as >> best they could, etc. > > > Not by tapping. International Morse requires dashes as well > as taps (dots). There is a tap code used in prisons that will > accomplish communications under those circumstances. And since > more people have been in prison than hold an amateur radio > license, seems that it would make more sense to require knowing > the tap code than to require knowing International Morse code. I seem to remember that the original Morse code was all clicks. I think the telegraph lines were DC current to electromagnetic clicking "receivers". The dashes were sort of implied by the spacing of the clicks...not that it matters to the antenna group, I guess. The only thing good about the prison system of taps mentioned earlier in the group is that if you know the grid, you know the "code". Extremely inefficient, however. Long live di-dah Article: 225036 of rec.radio.amateur.antenna Message-ID: <4486549E.7000802@fuse.net> Date: Wed, 07 Jun 2006 00:22:54 -0400 From: jawod Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <448624c0$0$6154$39cecf19@news.twtelecom.net> <448628bb$0$3693$ecde5a14@news.coretel.net> Cecil Moore wrote: > > > Please tell us when, in human history, it has ever been done. Yes. It was an episode of the old Adam-12 TV series. Patrolman was injured in a crashed cruiser. Mic out. but he could click the mic button...the guy on the other end directed him to "click once if you hear me and twice if you don't" Classic television: you had to be there. Article: 225037 of rec.radio.amateur.antenna Subject: Re: FS: High Quality Coax Connectors & Adapters at very low prices From: Larry References: <%fihg.6120$rS6.5893@fed1read11> Message-ID: Date: Wed, 07 Jun 2006 00:24:01 -0400 The spam is getting worse! "AAA RF Products" wrote in news:%fihg.6120$rS6.5893@fed1read11: > Path: > be01!atl-c01.usenetserver.com!news.usenetserver.com!border1.nntp.dca.gi > ganews.com!nntp.giganews.com!nx01.iad01.newshosting.com!newshosting.com > !68.1.17.232.MISMATCH!peer01.cox.net!cox.net!p01!fed1read11.POSTED!53ab > 2750!not-for-mail From: "AAA RF Products" > Newsgroups: > misc.industry.electronics.marketplace,rec.boats.electronics,rec.radio.a > mateur.antenna,rec.radio.amateur.boatanchors Subject: FS: High Quality > Coax Connectors & Adapters at very low prices Lines: 4 > X-Priority: 3 > X-MSMail-Priority: Normal > X-Newsreader: Microsoft Outlook Express 6.00.2900.2869 > X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 > X-RFC2646: Format=Flowed; Original > Message-ID: <%fihg.6120$rS6.5893@fed1read11> > Date: Tue, 6 Jun 2006 09:42:39 -0700 > NNTP-Posting-Host: 64.58.167.76 > X-Complaints-To: abuse@cox.net > X-Trace: fed1read11 1149612155 64.58.167.76 (Tue, 06 Jun 2006 12:42:35 > EDT) NNTP-Posting-Date: Tue, 06 Jun 2006 12:42:35 EDT > Organization: Cox Communications > Xref: usenetserver.com misc.industry.electronics.marketplace:126894 > rec.boats.electronics:160705 rec.radio.amateur.antenna:326563 > rec.radio.amateur.boatanchors:215022 X-Received-Date: Tue, 06 Jun 2006 > 12:42:35 EDT (be01) > > Please email sales@aaarfproducts.com or call 949 481 3154 (San > Clemente, CA, USA) for a copy of our latest catalog. > > > Article: 225038 of rec.radio.amateur.antenna From: blair thompson Subject: End-fed wire question. Date: Tue, 06 Jun 2006 21:34:26 -0700 Message-ID: <0ukc82prneu4c8u1pdnpe132g06353kvk2@4ax.com> I have a 63 ft. end-fed wire antenna which I am using with an MFJ-949 versa tuner, and 4 counterpoises cut for 1/4 wave on 15,20, 30 and 40 meters. Far end not very high, about 25 feet up a tree, shot up there with a slingshot. Pretty thick foliage right now, but not a lot of the wire is showing and in the clear as the near end of the wire slopes down almost to ground level (townhome QTH). Bit of an underperformer, and I was wondering whether it would be worth my while to install a ground rod in order to ground the tuner, and whether that might improve matters a bit, Thanks for any information. Blair VA7NA Article: 225039 of rec.radio.amateur.antenna From: "kd5sak" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4485eeaa$0$3704$ecde5a14@news.coretel.net> Subject: Re: Give up CB for ham? Message-ID: Date: Wed, 07 Jun 2006 04:36:52 GMT "Cecil Moore" wrote in message news:qLrhg.39959$4L1.32138@newssvr11.news.prodigy.com... > clfe wrote: > How do you send a 'dash' by tapping on a pipe? You > apparently could revolutionize prison communications > by providing an answer to that simple question. > -- > 73, Cecil http://www.qsl.net/w5dxp How about a fast double tap on the pipe (or bar) to signify a "dash"? It's not an elegant solution, but could be made to work. Those guys are probably not gonna try for 30 characters per minute anyway. Harold KD5SAK Article: 225041 of rec.radio.amateur.antenna From: wood@itd.nrl.navy.mil (J. B. Wood) Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 07:43:44 -0400 Message-ID: References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <23774-4485E9C0-784@storefull-3257.bay.webtv.net> <128c1e6mscrqe09@corp.supernews.com> In article <128c1e6mscrqe09@corp.supernews.com>, Roy Lewallen wrote: > Yes. American antenna salesmen haven't yet gotten as sophisticated as > the British inventors and purveyors of the CFA. But they're learning. Be > patient -- perhaps someday they'll reach that level. > The CFA proponents weren't sophisticated at all. The "inventors" probably read half of chapter one of an undergraduate electromagnetics textbook but forgot to read/understand the rest. Another source of embarrassment was that one of the CFA backers was a university EE professor. Go figure. Extraordinary claims but no extraordinary proof. BTW, in case you're interested, the British/Egyptian inventors' U.S. patent number is 5155495. It's patented so it must work... 73s from N4GGO, John Wood (Code 5550) e-mail: wood@itd.nrl.navy.mil Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337 Article: 225042 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: H FIELD ANTENNAS? Date: Wed, 7 Jun 2006 08:21:18 -0400 Message-ID: <128dh45bejvrd5d@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Dear Tom: Your message may one of the most interesting and unexpected that I have read in a long time. Some comments follow. Please note my extreme reluctance to engage in anything but a calm exchange of experiences and opinions. I have no interest in provoking you. Your experience does not seem to agree with experience at remote, flat, treeless sites here in Michigan. Please note the qualifiers in the last sentence. Especially in the UP of Michigan, at certain times of the year, P-noise is the major factor in limiting radio use. P-noise is not found on an antenna imbedded in a clump of trees when an antenna out in the open (many wavelengths from the first antenna) has P-noise. The follow-on is that since most sites are urban or suburban, few radio amateurs will experience P-noise. P-noise is observed when there is no rain nor thunderstorms, but plenty of wind. This is suggestive of moving charge discharging into the antenna. Of course, one could define this action as being "corona." Of course, if one places enough charge on a piece of metal eventually there will be "corona." Many antennas have a conductive path to earth that makes such an accumulation of charge unlikely. There is no doubt that an antenna experiencing P-noise will radiate and thus noise will be received by nearby antennas. That is why successful receiving antennas here in the flatland are placed a long distance from metallic objects. Most people have never heard P-noise because their site precludes same. A paper published in August about 1961 (IEEE Vehicular Transactions) is one of the few references that has been published that deals with means for reducing P-noise. The article involved a fixed, not mobile, antenna. It appears that additional work has not been published that deals significantly with fixed antennas. (Lots of papers exist dealing with aircraft antennas.) Your #6 is interesting. Unfortunately, there is so much radiation from what else is on a tall building that it is difficult to sort out where excess noise is coming from. An antenna inside of a slightly conductive radome that is placed a long distance from anything that could radiate might be different. Your #7 is especially interesting. Our EMC group has on the drawing board just such experimentation. We will be on the lookout for "end effects." Your note is a valuable observation. Regards, Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net wrote in message news:1149675056.576658.92120@c74g2000cwc.googlegroups.com... > > Reg Edwards wrote: > > Precipitation static, eg., from highly charged raindrops and fine snow > > or fine sand, impinging on the antenna wire, just causes an increase > > in receiver white noise level. It can be reduced but not removed by > > using a very thickly insulated antenna wire, like the inner conductor > > of a coaxial cable complete with its polyethylene jacket. > > ---- > > Reg. > > I've never seen a case of precitation static occuring that way. > > In every single case I've seen, whether on tall buildings, tall towers, > or antenna hear earth, it has always been corona discharges from the > antenna or objects near the antenna. > > How do I know this? > > 1.) I had side by side "insulated" and "unisulated" Beverage antenna > wires that are otherwide identical except for being spaced a few dozen > feet apart, and the antebnna pointed towards my tall towers had precip > static and the others did not. Both were equal in noise despite the > fact they are hit by the same rain or dust. > > 2.) I have Yagis on towers that are identical, and the LOWER antenna > almost never has precipitation static despite the fact they are hit by > the same rain or dust. > > 3.) I've had dipoles at various heights, and the lower dipole always > has much less precipitation staic than the high dipole despite the fact > they get the same rain or dust. > > 4.) The period of the noise has nothing at all to do with the number of > droplets hitting the antenna. It increases in pitch as the charge > gradient between earth and clouds builds, then when lightning flashes > it immediatly stops without time delay. > > 5.) On tall buildings on dark nights in storms, we could actually hear > the same pitch noise as the repeaters rebroadcast, and walk to the > noise source and actually see the corona. > > 6.) Antennas in fiberglass radomes were no quieter than bare metal > dipoles on tall buildings. > > 7.) I even used an electrostatic sprayer to charge droplets and hit an > antenna, and could only simulate noise when the antenna element had a > sharp point and I got near the sharp point...at which time I could see > faint corona. > > 73 Tom > Article: 225043 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Quad feedpoint Message-ID: Date: Wed, 7 Jun 2006 08:44:55 -0500 I just built a 3el 6m quad. Should I put a choke or balun at the feedpoint? What type? -- 73's de Ken KG0WX - Kadiddlehopper #11808, Flying Pigs #-1055, Grid EM17io, FT-857D, AL-84, Elecraft XG2, 4SQRP Tenna Dipper, Heath GD-1B Article: 225044 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: H FIELD ANTENNAS? References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Message-ID: Date: Wed, 07 Jun 2006 13:45:28 GMT w8ji@akorn.net wrote: > Reg Edwards wrote: >> Precipitation static, eg., from highly charged raindrops and fine snow >> or fine sand, impinging on the antenna wire, just causes an increase >> in receiver white noise level. It can be reduced but not removed by >> using a very thickly insulated antenna wire, like the inner conductor >> of a coaxial cable complete with its polyethylene jacket. > > I've never seen a case of precitation static occuring that way. I experienced that kind of static in Arizona with wind, extremely low humidity, and bare wire. I've never experienced it in East Texas. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225045 of rec.radio.amateur.antenna Subject: Re: End-fed wire question. From: chuck Date: Wed, 07 Jun 2006 09:53:31 -0400 Message-ID: <1149687760_46747@sp6iad.superfeed.net> References: <0ukc82prneu4c8u1pdnpe132g06353kvk2@4ax.com> <_MqdnV8xku6s9BvZRVnyiw@bt.com> Reg Edwards wrote: > "blair thompson" wrote >> I have a 63 ft. end-fed wire antenna which I am using with an > MFJ-949 >> versa tuner, and 4 counterpoises cut for 1/4 wave on 15,20, 30 and > 40 >> meters. Far end not very high, about 25 feet up a tree, shot up > there >> with a slingshot. Pretty thick foliage right now, but not a lot of > the >> wire is showing and in the clear as the near end of the wire slopes >> down almost to ground level (townhome QTH). >> >> Bit of an underperformer, and I was wondering whether it would be >> worth my while to install a ground rod in order to ground the tuner, >> and whether that might improve matters a bit, >> > ================================= > Blair, > A single ground rod will be virtually useless - that is unless it can > be driven into salt sea water. > In which case, it will be practically perfect! Not much gray area for ground rods in this Zoroasterian space. ;-) Well, as far as ground rods are concerned, it would be practically perfect, but your antenna as is would still not be. > If the radials are elevated above ground, then some improvement may be > achieved by allowing them to rest at ground level. This will increase > the effective height of the antenna. > > Better still, shallow-bury them. > > Even better, add more radials. Extra radials, on or underground, need > not be very long and not of any particular length. The more there are > up to a dozen or so, the merrier. > If the antenna is roughly a half-wave on 40 meters, mostly horizontal, I doubt that more radials will help much. > Important - try to get the near end of the wire as high as you can in > the air. Get some vertical wire into it. Can the near end be taken up > the side of the house and suspended from a chimney, TV antenna or rain > gutter or something? This will definitely make a noticeable > improvement. > ---- > Reg. > > If you are seeking more low-angle radiation for DX, then this will help and you may see more benefit from additional radials. You might consider attaching the guy to the chimney, etc., and running the "vertical" wire from the tuner up and away from the house. You don't want that vertical wire running right alongside the chimney or TV antenna support. Chuck ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- Article: 225046 of rec.radio.amateur.antenna From: "Caveat Lector" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4485eeaa$0$3704$ecde5a14@news.coretel.net> Subject: Re: Caught Sending Morse (was Give up CB for ham?) Message-ID: <_PAhg.178634$bm6.159481@fed1read04> Date: Wed, 7 Jun 2006 06:49:47 -0700 During long boring meetings at an Aerospace company, my buddy and I would send Morse by pencil taps, sharp tap was a dit and a tap-scrape was a dah. Worked well until a new manager gave his fist talk assuring us nothing would change - we tapped out BS. After the meeting, the new manager asked my buddy and I to stay for a moment after the meeting, With a smile, he sed Hi guys -- I'm W#XYZ Real call sign disguised to protect the guilty (;-) -- CL -- I doubt, therefore I might be ! "kd5sak" wrote in message news:EJshg.40736$fb2.8847@newssvr27.news.prodigy.net... > > "Cecil Moore" wrote in message > news:qLrhg.39959$4L1.32138@newssvr11.news.prodigy.com... >> clfe wrote: >> How do you send a 'dash' by tapping on a pipe? You >> apparently could revolutionize prison communications >> by providing an answer to that simple question. >> -- >> 73, Cecil http://www.qsl.net/w5dxp > > How about a fast double tap on the pipe (or bar) to signify a "dash"? It's > not an elegant solution, but could be made to work. Those guys are > probably not gonna try for 30 characters per minute anyway. > > Harold > KD5SAK > Article: 225047 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4486538A.5070005@fuse.net> Message-ID: Date: Wed, 07 Jun 2006 14:03:01 GMT jawod wrote: > I seem to remember that the original Morse code was all clicks. Wasn't there a strong click when the receiver circuit closed and a different weak click when the circuit opened? The length of time between those two types of clicks was either a dot or a dash? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225049 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Quad feedpoint References: Message-ID: <8gBhg.18641$VE1.11065@newssvr14.news.prodigy.com> Date: Wed, 07 Jun 2006 14:19:48 GMT Ken Bessler wrote: > I just built a 3el 6m quad. Should I put a choke or balun > at the feedpoint? What type? A few turns of coax will do the trick for 6m. How about this solution from an earlier posting? | | | Driven | Element | +====================================coax braid +------------------------------------coax center conductor | | ==============================+===coax braid | spacing | +--------------------------------+ | 1/4WL wire (~4.7') | -- 73, Cecil http://www.qsl.net/w5dxp Article: 225050 of rec.radio.amateur.antenna From: "Caveat Lector" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4486538A.5070005@fuse.net> Subject: Re: Give up CB for ham? Message-ID: Date: Wed, 7 Jun 2006 07:33:24 -0700 The first Morse machines scribed the dots and dashes on a moving strip of paper. Operators of the day found that they could decode the sound of the scriber by ear, so the scribing machines were scrapped. http://www.maxmon.com/1880ad.htm -- CL -- I doubt, therefore I might be ! "Cecil Moore" wrote in message news:p0Bhg.18634$VE1.9119@newssvr14.news.prodigy.com... > jawod wrote: >> I seem to remember that the original Morse code was all clicks. > > Wasn't there a strong click when the receiver circuit > closed and a different weak click when the circuit > opened? The length of time between those two types of > clicks was either a dot or a dash? > -- > 73, Cecil http://www.qsl.net/w5dxp Article: 225051 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <128ccnil05e0744@corp.supernews.com> Subject: Re: H FIELD ANTENNAS? Message-ID: Date: Wed, 7 Jun 2006 11:26:55 -0400 "Roy Lewallen" wrote in message news:128ccnil05e0744@corp.supernews.com... > Yuri Blanarovich wrote: >> . . . >> Roy, 'splain to him about this 1/8 or so thing. He still dungetit. > > Tom understands it, but I see you don't quite have a handle on it yet. > > Roy Lewallen, W7EL So I "don't get it" because I (and others) see the difference in reality, when electrostatic shield suppresses the local interference. You explain behavior of E and H field in the vicinity of antenna but that does not apply to "W8JI shield is the antenna" and "current at both ends of the loading coil is always the same". I will stick to my reality handle, rather than joining scientwist's chorus. 73 Yuri, K3BU Article: 225052 of rec.radio.amateur.antenna From: Tron Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 15:27:28 -0000 Message-ID: <128ds3056onlhb4@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> Roy Lewallen wrote: > > Bill Ogden wrote: > > OK, let me display my ignorance once again. > > > > There are many construction articles about ferrite-core antennas for the low > > bands. (Not to mention all the ferrite-core antennas in AM receivers.) Are > > these not H-field antennas, to a large extent? > > Only very locally, and only to a limited extent. > > When a signal originates far from an antenna, the response to E and H > fields is in the ratio of about 377 ohms, the impedance of free space. > This is true for *all antennas*. In other words, all antennas have the > same relative E and H response to signals originating far away. > > Very close to a small loop antenna, response is greater to an H field > than E field. It does respond to both, however, as all antennas must. As > you get farther away from the antenna, the response to the H field > decreases in relation to the E field response. At around an eighth > wavelength distance from the antenna, the response to E and H fields are > about the same as for a distant source. Beyond about an eighth > wavelength, the response to the H field is actually *less* than the > response to an E field compared to a source at a great distance. The > ratio of E to H field responses then decreases to the distant value as > you get farther from the antenna. > > In summary, the antenna responds more strongly to the H field if the > source is within about an eighth of a wavelength from the antenna. > Beyond that, it actually responds more strongly to the E field relative > to the H field than a short dipole or many other antennas -- you could > more properly call it an "E-field antenna" in its response to signals > beyond about an eighth wavelength. The difference in relative E and H > field response among all antennas becomes negligible at great distances; > for antennas which are small in terms of wavelength, the difference > becomes negligible beyond about a wavelength. > > Now, suppose you could make a magic antenna which would respond only to > the H field of a signal originating at any distance from the antenna > (which is impossible). "A system for determining the modulation imposed on a curl-free magnetic vector potential field.": http://jnaudin.free.fr/html/tepvppl.htm Other 'magic' antennae: http://rugth30.phys.rug.nl/quantummechanics/ab.htm Robust OP AMP Realization Of Chua's Circuit: http://citeseer.ist.psu.edu/kennedy92robust.html > What advantage would it have over a real antenna? I read the main reason was less electrostatic interference but with less immunity to strong nearby stations. Does the magnetic field really have less noise than the E-field? Polarization is also an interesting component. > Remember that the E/H ratio of any signal originating very far away is > 377 ohms, regardless of what kind of antenna or source it came from. I seem to recall this had something to do with the speed of light not being infinite. > > Roy Lewallen, W7EL Article: 225053 of rec.radio.amateur.antenna From: "Bill Ogden" References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Subject: Re: H FIELD ANTENNAS? Message-ID: Date: Wed, 7 Jun 2006 12:05:09 -0400 I understand that E and H fields are intrinsic parts of the same thing (for radio waves, etc), and I am not trying to separate them along the lines discussed by some list participants. I would think that the E and H ratio of 377 is a function of the SI units of measurement involved. It would seem that there is the same amount of energy (at different and selected instances) in the E and H waves, and different units of measurement could produce a ratio of 1:1 (or anything else, with appropriate units of measurement). To return to the ferrite rod antenna: Ignoring the directional null capability (which might be very useful in some real-world circumstances) is there any advantage to a small ferrite rod antenna over a short wire antenna (assuming perfect amplifiers, as needed, following the antennas and assuming 160m or 80m usage)? As mentioned earlier, there have been a number of construction articles over the years explaining how a ferrite rod antenna did wonderful things for 160/80 operation. I have wondered if these results are generally valid, or were the result of the authors' pride in their works, or happened because the directional null abilities solved a local problem. Bill - W2WO Article: 225054 of rec.radio.amateur.antenna From: Tron Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 15:45:43 -0000 Message-ID: <128dt579n3outf2@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Cecil Moore wrote: > > w8ji@akorn.net wrote: > > Reg Edwards wrote: > >> Precipitation static, eg., from highly charged raindrops and fine snow > >> or fine sand, impinging on the antenna wire, just causes an increase > >> in receiver white noise level. It can be reduced but not removed by > >> using a very thickly insulated antenna wire, like the inner conductor > >> of a coaxial cable complete with its polyethylene jacket. > > > > I've never seen a case of precitation static occuring that way. > > I experienced that kind of static in Arizona with wind, extremely > low humidity, and bare wire. I've never experienced it in East > Texas. Isn't this the triboelectric effect? I read this was a big problem for certain newer wireless applications. Energized TV antennas always feel 'gritty' when I brush my fingers lightly across them. Why is that? I also get a very mild shock sometimes, but that gritty electric sandpaper friction is very strange. Also the indoor TV antenna collects dust and vaporized cooking oil like there's no tomorrow. Is this like a Tesla coil? > -- > 73, Cecil http://www.qsl.net/w5dxp Article: 225055 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: H FIELD ANTENNAS? References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Message-ID: Date: Wed, 07 Jun 2006 15:52:47 GMT Bill Ogden wrote: > To return to the ferrite rod antenna: Ignoring the directional null > capability (which might be very useful in some real-world circumstances) is > there any advantage to a small ferrite rod antenna over a short wire antenna? For the 1980's CA 75m mobile antenna shootouts, a ferrite rod antenna was used for receiving because the local human bodies had much less of an effect upon it than, for instance, upon a hamstick antenna. I always assumed it was because a human body has more of an effect on the E-field than it does on the H-field. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225056 of rec.radio.amateur.antenna From: "Mike Y" References: Subject: Re: sealing coax holes in outside wall Message-ID: Date: Wed, 7 Jun 2006 12:04:17 -0700 When I used to work for a power company, they used a 'tape' that was like a strip of rubber just under maybe 1/8" thick. When you pulled it off the roll, you had to remove a paper backing, then 'stretch' the tape to activate it. Then when it was wrapped around a connection, it would 'cure' into a solid mass. I think RS used to sell something similar, but have no idea what it would be called. You might try some industrial electrical supply houses. Mike Article: 225057 of rec.radio.amateur.antenna From: Roger Subject: Re: sealing coax holes in outside wall Message-ID: References: Date: Wed, 07 Jun 2006 12:19:09 -0400 On Tue, 6 Jun 2006 20:36:46 -0700, "Sal M. Onella" wrote: > >"Chris W" <1qazse4@cox.net> wrote in message >news:fy7hg.52579$9c6.12825@dukeread11... >> Can anyone tell me what the official name of the putty they use to seal >> the holes you run your coax through so bugs don't crawl in the wall or >> water doesn't get in? I like to get all my hardware type items from >> mcmaster.com. I'm sure they have it, if I just know what it is called I >> can find it on their website. > I use the "expandable foam" that comes in a can about the size of a spray paint can. There are two types. The yellow foam that expands and gets hard which also is sensitive to UV which will cause it to change color (darken). Don't use this around areas where the pressure of expansion can cause problems like sealing around a door. They also have a "soft/flexible" version that is white and costs a bit more. It's what I use to block the large conduit between the tower and basement. http://www.rogerhalstead.com/ham_files/cablebox.htm Shows the conduit at the tower and coming in the basement. I just squirted the stuff in. I wasn't worried about it being pretty, just effective. With care you can be a lot more artistic. <:-)) It's easy to apply and easy to remove when necessary. Bugs and critters appear to not like the stuff. I like it far better than the putty. The yellow foam is a tad over $3 USD a can while the white, flexible stuff is $4 or $5 a can. Both are usually available at Lowe's, Builder's Square, and hard ware stores. Roger Halstead (K8RI & ARRL life member) (N833R, S# CD-2 Worlds oldest Debonair) www.rogerhalstead.com >I was thinking "electrician's putty" or similar -- what we used to call >"monkey shit" in the Navy, but I couldn't get a good match on Google for >those terms. While mulling this over, I remembered also Plumbers Putty. >While generally not used for coax, I have used it under sinks and in the >garage for sealing around pipe penetrations. What I have is light tan in >color. It stays soft and flexible (but I don't know what sunlight does to >it or whether it will take paint). It's cheap and available and might be >just what you need. > Article: 225058 of rec.radio.amateur.antenna From: "Steven R. Jones" Subject: How to model linear loading in shortened dipole of vertical using EZNEC? Message-ID: Date: Wed, 07 Jun 2006 13:25:44 -0400 I want to work out a design for a linear loaded off center fed vertical dipole for 75M (perhaps will work multiband as well?) using linear loading in an "S" configuration, i.e: feedpoint I-----------------------------------()-------------I I I I----------------------------------I I------------I I I -----------------------------------I I------------- Which per my reading should let me design a 75M vertical that is only 60% of the length of a conventional radiator. A recent article in QST showed the successful use of 450 ohm ladder line with interwoven 3rd wire as a conveient way to build this sort od linearly loaded design. In attempting to model this design in EZNEC, I do not seem to get the loading effect and shorter length of the radiators to achieve resonance, nor do I get the feedpoint impedance lowering that is described for this sort of loading. I was hoping that the OCFD design would allow direct feed through a choke balun without having to deal with impedance transformations. with either an excessively low center feed impedance (with loading) or the typical ~200 feedpoint impedance and 4:1 balun required with the OCFD design at about 1/3 distance from one end. Any thoughts or prior experience to share? Steve KQ4WB Article: 225059 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Yet another 6m 3el Quad question Message-ID: Date: Wed, 7 Jun 2006 12:22:22 -0500 My Quad is all built and I'm waiting or FedEx to deliver my rotor. I built the quad out of wood, with a 1-1/4" dia pine boom and 4' mast plus 1/4"x48" spruce dowels for spreaders. I used insulated 16g stranded wire for the elements. All the wood is either painted or treated with sealer. Problem is I just broke a spreader moving the antenna and I'm worried about how fragile the whole design is. Would the performance change much if I used 1/4" aluminum rods instead? Maybe I should just get some fiberglass resin and paint the spreaders with several coats? How about wrapping them in re-enforced boxers tape (the good stuff with fibers in the tape)? Thanks for the help, guys.... -- 73's de Ken KG0WX - Kadiddlehopper #11808, Flying Pigs #-1055, Grid EM17io, FT-857D, AL-84, Elecraft XG2, 4SQRP Tenna Dipper, Heath GD-1B Article: 225060 of rec.radio.amateur.antenna From: "Steven R. Jones" Subject: Re: How to model linear loading in shortened dipole of vertical using EZNEC? Message-ID: References: Date: Wed, 07 Jun 2006 13:30:43 -0400 sorry, the diagram came out mangled on the post. the idea is a derivative of the construction used in "The K4VX linear loaded dipole for 7 MHz" QST, July 2002, pages 40-42. Thanks Steve On Wed, 07 Jun 2006 13:25:44 -0400, Steven R. Jones wrote: > I want to work out a design for a linear loaded off center fed vertical > dipole for 75M (perhaps will work multiband as well?) using linear loading > in an "S" configuration, i.e: > feedpoint > I-----------------------------------()-------------I > I I > I----------------------------------I I------------I > I I > -----------------------------------I I------------- > > Which per my reading should let me design a 75M vertical that is only 60% > of the length of a conventional radiator. A recent article in QST showed > the successful use of 450 ohm ladder line with interwoven 3rd wire as a > conveient way to build this sort od linearly loaded design. In attempting > to model this design in EZNEC, I do not seem to get the loading effect and > shorter length of the radiators to achieve resonance, nor do I get the > feedpoint impedance lowering that is described for this sort of loading. > I was hoping that the OCFD design would allow direct feed through a choke > balun without having to deal with impedance transformations. with either > an excessively low center feed impedance (with loading) or the typical > ~200 feedpoint impedance and 4:1 balun required with the OCFD design at about 1/3 distance from > one end. > > Any thoughts or prior experience to share? > > Steve > KQ4WB Article: 225061 of rec.radio.amateur.antenna Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? From: Ed References: Message-ID: Date: 07 Jun 2006 17:59:49 GMT > No more automatic renewals. Individuals must retest and pass all elements > required for their license class. > > > The passing score for written exams needs to be raised to 85%. > > > Code elements should be 13 wpm for General, and 20 wpm for Extra. > > > Make the no-code Tech license one year non-renewable. You forgot one item.... abolish the VEC program and mandate that all candidates must test at an FCC Field Office. Also, it would be nice to abolish transistors and madate using only tubes, too! :^) Ed K7AAT Article: 225062 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Have any of you mailed this to your ARRL Division directors and Date: Wed, 07 Jun 2006 15:03:27 -0400 Message-ID: References: Ed wrote: >> No more automatic renewals. Individuals must retest and pass all > elements >> required for their license class. >> >> >> The passing score for written exams needs to be raised to 85%. >> >> >> Code elements should be 13 wpm for General, and 20 wpm for Extra. >> >> >> Make the no-code Tech license one year non-renewable. > > > > You forgot one item.... abolish the VEC program and mandate that > all candidates must test at an FCC Field Office. > > > Also, it would be nice to abolish transistors and madate using only > tubes, too! :^) All licenses should be terminated, immediately, and future testing will be a minimum of 110 wpm Morse code in a language that the applicant does not know. All sent straight key. Written tests will be changed to essay type. The applicant must demonstrate mastery of all aspects of RF discipline at the PhD level. Since people can look up answers in a book as well as a test question pool, all work must be new and cutting edge. Any answer that can be found in a book will disqualify the applicant. Upon the successful defense of the applicant's thesis, a 20 year waiting period starts. The work done by the applicant in pursuit of his license must be demonstrated to have a lasting and profound effect upon the RF discipline and especially so on the Amateur radio community. There may only be 2 hams left, but just imagine how superior they can feel about themselves........ Article: 225063 of rec.radio.amateur.antenna From: Allodoxaphobia Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Date: 7 Jun 2006 19:29:02 GMT Message-ID: References: On Wed, 07 Jun 2006 15:03:27 -0400, Michael Coslo wrote: > > <-BIG snip-> > > There may only be 2 hams left, but just imagine how superior they can > feel about themselves........ And, the rec.radio.amateur... ng's will still suffer from trolls and off-topic postings. Article: 225064 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 12:39:34 -0700 Message-ID: <128earr46e4i34e@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <128ccnil05e0744@corp.supernews.com> My reality, and Tom's, fits with the clear explanations in Johnson's _Antenna Engineering Handbook_ (successor to Jasik); King and Harrison's _Antennas and Waves_; King, Mimno, and Wing's _Transmission Lines, Antennas, and Wave Guides_; and undoubtedly others, since it comes from basic electromagnetic principles. I explained the nature of the E and H fields from a small loop antenna. This is the sum of the fields from each part of the loop. It is not representative of the field in the small region between the wire and shield of a "shielded" loop, as you seem to be trying to infer. If you'd spend a fraction of the time studying that you spend desperately trying to find something wrong with anything Tom says, you'd have a much better understanding of how antennas work. Roy Lewallen, W7EL Yuri Blanarovich wrote: > "Roy Lewallen" wrote in message > news:128ccnil05e0744@corp.supernews.com... >> Yuri Blanarovich wrote: >>> . . . >>> Roy, 'splain to him about this 1/8 or so thing. He still dungetit. >> Tom understands it, but I see you don't quite have a handle on it yet. >> >> Roy Lewallen, W7EL > > So I "don't get it" because I (and others) see the difference in reality, > when electrostatic shield suppresses the local interference. You explain > behavior of E and H field in the vicinity of antenna but that does not apply > to "W8JI shield is the antenna" and "current at both ends of the loading > coil is always the same". > > I will stick to my reality handle, rather than joining scientwist's chorus. > > 73 Yuri, K3BU > > Article: 225065 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 12:53:57 -0700 Message-ID: <128ebmplg6g9080@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> Bill Ogden wrote: > I understand that E and H fields are intrinsic parts of the same thing (for > radio waves, etc), and I am not trying to separate them along the lines > discussed by some list participants. > > I would think that the E and H ratio of 377 is a function of the SI units of > measurement involved. It would seem that there is the same amount of energy > (at different and selected instances) in the E and H waves, and different > units of measurement could produce a ratio of 1:1 (or anything else, with > appropriate units of measurement). Yes, that's correct. What I tried to do in my explanation was to relate the E/H ratio near a small loop with that of free space. That makes the units of measure immaterial. > To return to the ferrite rod antenna: Ignoring the directional null > capability (which might be very useful in some real-world circumstances) is > there any advantage to a small ferrite rod antenna over a short wire antenna > (assuming perfect amplifiers, as needed, following the antennas and assuming > 160m or 80m usage)? You get a greater effective aperture (aka "capture area", and directly related to "effective length") from the ferrite rod antenna for a given physical size. This results in a larger signal for a given impinging field strength. If you had perfect amplifiers, that would make no difference, but real amplifiers generate noise, so a larger signal results in a better signal/noise ratio when you're at the level where the amplifier noise dominates the system noise figure. But if the signal level is large enough so that atmospheric noise dominates, having a greater aperture doesn't present any advantage. > As mentioned earlier, there have been a number of construction articles over > the years explaining how a ferrite rod antenna did wonderful things for > 160/80 operation. I have wondered if these results are generally valid, or > were the result of the authors' pride in their works, or happened because > the directional null abilities solved a local problem. Anecdotal reports of "wonderful things" should always be highly suspect, and placebo effect high on the list of possible causes. It might be easier to get a good null with a ferrite rod antenna than with a casually built antenna of some other kind, and that would be a big potential advantage. When considering the value of anecdotal reports, consider the widely reported benefits of various kinds of speaker cable, and the staggering amount of money that's being extracted from the believers. Roy Lewallen, W7EL Article: 225066 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: End-fed wire question. Date: Wed, 07 Jun 2006 12:58:35 -0700 Message-ID: <128ebvef3u49he6@corp.supernews.com> References: <0ukc82prneu4c8u1pdnpe132g06353kvk2@4ax.com> <4486a95f@nntp.zianet.com> BKR wrote: > > End fed wires must always be used against an efficient ground system > consisting of a large number of radials or a tuned counterpoise for each > frequency. > > A single ground rod is normally fairly poor. It depends on the length of the wire. If it's near an odd number of quarter wavelengths long, the radiation resistance between the end and ground will be low, and a good ground system is necessary to get good efficiency. If it's significantly shorter than a quarter wavelength, the resistance is lower yet and a very good system is required. On the other hand, if it's close to an integral number of half wavelengths, the resistance will be high, and you can get by with a very poor ground system -- in many cases just a ground rod -- without sacrificing a significant amount of efficiency. That's the reason why a half wave antenna works so well on an HT. Roy Lewallen, W7EL Article: 225067 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: H FIELD ANTENNAS? Date: Wed, 07 Jun 2006 13:21:22 -0700 Message-ID: <128eda58dva2n33@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <23774-4485E9C0-784@storefull-3257.bay.webtv.net> <128c1e6mscrqe09@corp.supernews.com> J. B. Wood wrote: > . . . It's patented so it must work... Yeah, like U.S. patent 6,025,810, "Hyper-Light-Speed Antenna" (http://tinyurl.com/h546u). Roy Lewallen, W7EL Article: 225068 of rec.radio.amateur.antenna From: "Brian Hill" References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Message-ID: Date: Wed, 7 Jun 2006 16:22:52 -0500 "John S." wrote in message news:1149714609.565540.160300@c74g2000cwc.googlegroups.com... > > New Ham wrote: >> Did I get ripped off? > > You might try a Stetson. > four or five X beaver John? BH Article: 225069 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <128ccnil05e0744@corp.supernews.com> <128earr46e4i34e@corp.supernews.com> Subject: Re: H FIELD ANTENNAS? Message-ID: Date: Wed, 7 Jun 2006 18:30:50 -0400 "Roy Lewallen" wrote > > If you'd spend a fraction of the time studying that you spend desperately > trying to find something wrong with anything Tom says, you'd have a much > better understanding of how antennas work. > > Roy Lewallen, W7EL > Congratulations Roy, you have nove graduated from "W8JI school of personal mud slinging" when running out of arguments. How perceptive: " ...desperately....anything Tom says...." "Better understanding" - you mean swallowing fallacies you scientwists proclaim? I will stick with my understanding of how antennas work and I can measure, vs. your misapplied theories why it "can't be so". 73 Yuri, K3BU Article: 225070 of rec.radio.amateur.antenna From: "Gil" References: Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Message-ID: Date: Wed, 7 Jun 2006 19:12:12 -0400 Ed wrote: >> No more automatic renewals. Individuals must retest and pass all >> elements required for their license class. >> >> >> The passing score for written exams needs to be raised to 85%. >> >> >> Code elements should be 13 wpm for General, and 20 wpm for Extra. >> >> >> Make the no-code Tech license one year non-renewable. > > > > You forgot one item.... abolish the VEC program and mandate that > all candidates must test at an FCC Field Office. > > > Also, it would be nice to abolish transistors and madate using only > tubes, too! :^) > > > > Ed K7AAT Tubes are for appliance operators...real hams use SPARK!!! Hmm, wonder what a spark-gap transmitter would do to a BPL Internet deployment. Might have to try... Article: 225071 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: sealing coax holes in outside wall References: Message-ID: Date: Wed, 07 Jun 2006 23:19:49 GMT Think it scotch #23 tape (and several other numbers . Home Depot and Lowes has the stuff (Not to be confused with "Coax Connector Sealant" Radio shack # 278-1645, which is also great for sealing connectors against the weather). Great for weatherproofing, but needs to be covered (it is ultravilot sensitive) But- NOT to use it to plug holes! Dux Seal (a.k.a. "Monkey Shit" is MUCH BETTER-- Jim NN7K Mike Y wrote: > When I used to work for a power company, they used a 'tape' that was > like a strip of rubber just under maybe 1/8" thick. When you pulled it off > the roll, you had to remove a paper backing, then 'stretch' the tape to > activate it. Then when it was wrapped around a connection, it would > 'cure' into a solid mass. > > I think RS used to sell something similar, but have no idea what it would > be called. > > You might try some industrial electrical supply houses. > > Mike > > Article: 225072 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Message-ID: Date: Wed, 07 Jun 2006 23:31:19 GMT Reminds me of the time (many years ago), when the new kid on the gang was ordered to "Wash the Dishes" (microwave ), on a 150 foot tower ! Kid decided it was time to quit! Had to tell him it was a JOKE, or get the WHOLE Gang in hot water !!! Jim NN7K Brian Hill wrote: > "John S." wrote in message > news:1149714609.565540.160300@c74g2000cwc.googlegroups.com... > >>New Ham wrote: >> >>>Did I get ripped off? >> >>You might try a Stetson. >> > > > four or five X beaver John? > > BH > > Article: 225073 of rec.radio.amateur.antenna Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. From: Dave Oldridge References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Message-ID: Date: Wed, 07 Jun 2006 23:42:40 GMT Jim - NN7K wrote in news:blJhg.19147 $VE1.18282@newssvr14.news.prodigy.com: > Reminds me of the time (many years ago), when the > new kid on the gang was ordered to "Wash the > Dishes" (microwave ), on a 150 foot tower ! Kid > decided it was time to quit! Had to > tell him it was a JOKE, or get the WHOLE Gang > in hot water !!! Jim NN7K Yeah. When I was in the RCAF many years ago, a common thing was to ask a newbie to go to the tool crib for a bucket of propwash. -- Dave Oldridge+ ICQ 1800667 Article: 225074 of rec.radio.amateur.antenna Message-ID: <448765D1.5060004@fuse.net> Date: Wed, 07 Jun 2006 19:48:33 -0400 From: jawod Subject: Re: Have any of you mailed this to your ARRL Division directors and References: > > > You forgot one item.... abolish the VEC program and mandate that > all candidates must test at an FCC Field Office. > Hell, do it right. Transfer ham radio to the Food and Drug Administration where we know we all belong. Annual meat inpections mandatory. > > Also, it would be nice to abolish transistors and madate using only > tubes, too! :^) > > > > Ed K7AAT Article: 225075 of rec.radio.amateur.antenna Message-ID: <448767E7.4040009@fuse.net> Date: Wed, 07 Jun 2006 19:57:27 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> John S. wrote: > New Ham wrote: > >>Did I get ripped off? > > > You might try a Stetson. > Try a Dunce Cap (low capacitance) attached to your screwdriver and manually adjust until your dip meter reads moron :) Article: 225076 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Wed, 07 Jun 2006 19:21:51 -0500 Message-ID: <128ercucqikj3b0@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <1149724604.928282.248280@u72g2000cwu.googlegroups.com> John S. wrote: > Or looking for a left-handed crescent wrench and fetching a bucket of > prop wash. The problem with this joke is that the wrench exhists. Handedness in a wrench is determined by which thumb closes the jaws. Right thumb right hand wrench, left thumb left handed wrench. I have a left handed crescent type wrench. Where was it made? POLAND of course. Wrench available for inspection. Dave WD9BDZ > > > Jim - NN7K wrote: > >>Reminds me of the time (many years ago), when the >>new kid on the gang was ordered to "Wash the >>Dishes" (microwave ), on a 150 foot tower ! Kid >>decided it was time to quit! Had to >>tell him it was a JOKE, or get the WHOLE Gang >>in hot water !!! Jim NN7K >> >> >> >>Brian Hill wrote: >> >>>"John S." wrote in message >>>news:1149714609.565540.160300@c74g2000cwc.googlegroups.com... >>> >>> >>>>New Ham wrote: >>>> >>>> >>>>>Did I get ripped off? >>>> >>>>You might try a Stetson. >>>> >>> >>> >>>four or five X beaver John? >>> >>>BH >>> >>> > > Article: 225077 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: H FIELD ANTENNAS? References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> <128dh45bejvrd5d@corp.supernews.com> <1149721730.564878.262550@j55g2000cwa.googlegroups.com> Message-ID: Date: Thu, 08 Jun 2006 01:37:13 GMT w8ji@akorn.net wrote: > J. Mc Laughlin wrote: >> P-noise is observed when there is no rain nor thunderstorms, but plenty >> of wind. This is suggestive of moving charge discharging into the antenna. > > So how does it get there? How does it build up? Where is the spark arc > or sizzle? This is a well known phenomenon in Arizona. What else, besides charged dust particles, could cause arcing at coax connectors on a perfectly clear windy day? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225078 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: H FIELD ANTENNAS? Date: Wed, 7 Jun 2006 21:47:20 -0400 Message-ID: <128f0bfir75r9ec@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> <128dh45bejvrd5d@corp.supernews.com> <1149721730.564878.262550@j55g2000cwa.googlegroups.com> Dear Tom: It appears that two noise mechanisms exist. The two are P-noise and corona noise. A receiver will experience close to white noise in both cases. However, corona noise tends to be accompanied by sudden stops and starts and P-noise starts with a sequence of perceptibly time spaced pops that increase in rate. If there is corona off of the top of a structure then it is reasonable to expect the antennas most close to the corona will "hear" more noise than the antennas that are farther away (such as below). It is also to be expected that moving charged particles that are higher above the ground will carry more charge on the average than charged particles that are moving near the ground. Depending on the wind and gradient, I expect that there is a height below which few charged particles are found when higher above ground charged particles are common. In short: If one can see corona, it will be the dominate noise source. If the gradient with altitude is not sufficient for corona, and weather conditions are such that moving charged particles exist, then out in the open the higher antennas are expected to have more discharges from moving charged particles per second and more noise than experienced by lower antennas. I have offered an alternative explanation for why, absent corona, higher antennas might well experience more noise. Actual precipitation (rain, snow, hail) is not needed for P-noise. Moving dust particles can carry charge and become charged. The noise does follow the "pattern of the particle rate." However, as you understand from other work, when the rate becomes high enough compared to the bandwidth of the receiver the result is essentially indistinguishable from white noise. Even with a 400 Hz bandwidth, the onset of P-noise is unique and comprises a sequence of pops that either die away or increase in rate to produce prodigious amounts of noise. I have used a time blanking circuit - noise clipper - and find that it is effective at lower rates. Corona noise does not seem to have the same temporal characteristics. A moving charged particle is able to discharge into an insulated conductor with aplomb. It is the very-close-to-the-antenna sudden accelerations of charge that produce noise (radio waves). What has shown promise is the use of slightly conductive coverings. The theory is that the amplitude of the pop will be reduced because the rate of charge transfer will be slowed. UV resistant materials that are easy to apply and that are not expensive seem not to exist. Obviously, too much conductivity would be ineffective. Absent actual corona, a noise mechanism is contended that comprises the sudden transfer of some or all of the charge on a moving charged particle (that occurs naturally) into an antenna's structure, support or even into insulation around same. A near optimum, HF, DX, low-noise receiving antenna is a small, horizontal, unturned loop antenna with an amplifier that is mounted on a wood pole having no metal inserts. The pole is some 200 meters from any exposed metal. The coax that runs up the pole to the amplifier is encased in conductive, plastic conduit as is the loop's wire. This antenna has close to a null at the zenith and is omnidirectional in azimuth. It is contended that what I have observed is not in conflict with what you have observed with corona discharges. 73 Mac N8TT P.S. Some months ago you asked about V antennas for low HF or MF use involving a 300 foot tower. I found that an interesting topic and did some analysis, which I tried to sent to you. Unfortunately, the E-mail address did not work. My conclusion, was, as well as I am able to remember, the same as yours: at the low frequencies involved, the effort did not have a reasonable pay-back. -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net wrote in message news:1149721730.564878.262550@j55g2000cwa.googlegroups.com... > J. Mc Laughlin wrote: > > > P-noise is not found on an antenna imbedded in a clump of trees when an > > antenna out in the open (many wavelengths from the first antenna) has > > P-noise. The follow-on is that since most sites are urban or suburban, few > > radio amateurs will experience P-noise. > > That does not disagree with anything I said. A lower antenna surrounded > by taller objects is not subject to the same high voltage gradient as > an antenna out in a flat clear field. > > > P-noise is observed when there is no rain nor thunderstorms, but plenty > > of wind. This is suggestive of moving charge discharging into the antenna. > > So how does it get there? How does it build up? Where is the spark arc > or sizzle? > > > Of course, one could define this action as being "corona." Of course, if > > one places enough charge on a piece of metal eventually there will be > > "corona." Many antennas have a conductive path to earth that makes such an > > accumulation of charge unlikely. > > The fact is grounded or ungrounded antennas all behave the very same > way. Ask anyone who has yagis on towers. It is a potential difference > between earth and the atmosphere around the antenna. It isn't the > antenna charging up so much differently than earth. It is the > difference in potential between the antenna and the space around the > antenna. > > Remember those old tall mast wooden sailing ships soaked with saltwater > and the fire off the yardarms at night? > > > Your #6 is interesting. Unfortunately, there is so much radiation from > > what else is on a tall building that it is difficult to sort out where > > excess noise is coming from. An antenna inside of a slightly conductive > > radome that is placed a long distance from anything that could radiate might > > be different. > > You can walk right up to the noise source, and even see the corona at > night. It's very easy to take a FSM with audio monitor or AM receiver > with S meter and walk the roof for strongest noise, and it will > generally take you right to the tallest sharpest object (grounded or > not) on the roof. > > The last place you want to be is the tallest antenna on the building. > Get high winds or inclement weather and you will be destined for > noise....grounded antenna or not. > > We serviced dozens of repeaters and a few STL or Remote links in the > 70's, it was a pattern that repeated. > > I have a suggestion. Go to a forum where there are many people with > antennas at various heights, like a contesting reflector. Ask people > who have similar or identical antennas at various heights on a single > tall tower what they observe during high winds, nasty weather, or rain. > The very same wind and the very same moisture is impacting all of the > antennas, but without fail they will tell you the lower antennas are > always much better and the taller antennas are the first to go. > > If the P-staic is actually coming from the particles or moisture in air > striking the antenna, and if the same basic sample of weather is at all > the antennas, why are the upper antennas affected more? > > If it is the conductor charging, why do plumber's delight antennas or > folded elements with grounded centers have the same noise as insulated > elements? > > If it is moisture or particles striking the antenna causing the > problem, why is an insulated antenna with a single sharp protrusion > just as noisey as a bare antenna? Why doesn't the noise follow the > pattern of the particle rate, and why does it occur (as you even seemed > to say) when there is no actual precipitation? > > Since I've always had towers taller than 100 feet, and since I've > worked on VHF and UHF systems that had to stay up during storms, I've > spent a lot of time looking at this. I've not found anything that > points to the antenna charging differently than earth or being struck > by charged particles. > > 73 Tom > Article: 225079 of rec.radio.amateur.antenna Date: Wed, 07 Jun 2006 21:51:58 -0500 From: Tom Ring Subject: Re: Have any of you mailed this to your ARRL Division directors and References: Message-ID: <448790cf$0$6154$39cecf19@news.twtelecom.net> yea right wrote: >>Code elements should be 13 wpm for General, and 20 wpm for Extra. >> > > > No Way! 35wpm for extra! > Come on, that sets the bar way too low. 100 wpm CW, and 45 baud RTTY. RTTY is the wave of the future, after all. And we add a new class called "Extra Extra Read All About It!" where you have to copy Hellschreiber and PSK31 and copy and whistle 1200 baud packet. tom K0TAR Article: 225080 of rec.radio.amateur.antenna From: Mike Burch Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4485f6e7$0$26775$88260bb3@free.teranews.com> Message-ID: <19Nhg.22056$No1.19537@attbi_s71> Date: Thu, 08 Jun 2006 03:51:25 GMT Thanks for stepping up to the plate and admitting it. You got some points for that. :-) LLOYD THE LARDASS LOSER DAVIES wrote: > I'm an inbred alabama hick and I hate CB. > > > Lloyd Davies N0VFP > Cow Cornholer > Nutsackkk Gobbler > Dumpster Dweller > in Athens, Alabama > > wrote in message > news:1149534276.955122.310050@i40g2000cwc.googlegroups.com... >> Alot of people are telling me that CB is just for inbred hicks and that >> I should replace the CB in my truck with a ham radio. What do you >> thjink? >> > > > Article: 225081 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: H FIELD ANTENNAS? Date: Wed, 7 Jun 2006 23:57:10 -0400 Message-ID: <128f7uvfmnrlq36@corp.supernews.com> References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> <128dh45bejvrd5d@corp.supernews.com> <1149721730.564878.262550@j55g2000cwa.googlegroups.com> <128f0bfir75r9ec@corp.supernews.com> <1149737733.436349.216110@f6g2000cwb.googlegroups.com> Dear Tom: Thank you for your ideas and the reference. Let us leave it that we see things differently. Readers have the ability to learn from contrasting each of our viewpoints. I have always included my E-mail address in my communications. I must to bed - tomorrow is the last lab day of the semester and I anticipate many questions directed to the proximate final exams. 73, Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net wrote in message news:1149737733.436349.216110@f6g2000cwb.googlegroups.com... > J. Mc Laughlin wrote: > > > It appears that two noise mechanisms exist. The two are P-noise and > > corona noise. A receiver will experience close to white noise in both > > cases. However, corona noise tends to be accompanied by sudden stops and > > starts and P-noise starts with a sequence of perceptibly time spaced pops > > that increase in rate. > > Pops are caused by something charging and flashing over. All it takes > to eliminate pops is a leak resistance or a leak choke slow enough to > keep the antenna from charging. > > I've never heard the slow popping noise called P-static by anyone I > know, but that doesn't say some people don't call it that. > > I have dipole high in the air, and on a clear day with a fair breeze > they will knock someone right on their butt if the feeder is unhooked > and the antenna allowed to charge. It does that dust or no dust, > although nasty weather seems to greatly increase charge rate. > > It's easy to see why that happens. > > http://www.who.int/peh-emf/publications/3_EHC_232_Sources_and_Exposure.pdf > > There is a significant electric field as we increase height even in > fair weather. Even though that is a very high impedance field, it > doesn't take air movement to charge a high conductor that is > well-insulated. > > > I have offered an alternative explanation for why, absent corona, higher > > antennas might well experience more noise. > > True, but a height change of just a few meters on a building or tower > hundreds of meters tall makes a big difference as do sharp compared to > blunt points on an antenna. > > During a rainstorm, when most people complain about corona, droplets > from the very same sources are hitting lower and upper antennas. The > noise does NOT follow the pattern or rate of raindrops hitting the > antenna, and the upper antenna is always significantly noisier than the > lower antenna. > > > Actual precipitation (rain, snow, hail) is not needed for > P-noise. > > Of course not. It is a voltage gradient problem. > > > Moving dust particles can carry charge and become charged. The noise does > > follow the "pattern of the particle rate." > > I've never seen it do that. But I'll keep watching for it. > > > P.S. Some months ago you asked about V antennas for low HF or MF use > > involving a 300 foot tower. I found that an interesting topic and did some > > analysis, which I tried to sent to you. Unfortunately, the E-mail address > > did not work. > > That's because the email address listed by Google for me is a dead > address. If it was live, it would be useless with spam and virus. > > 73 Tom > Article: 225082 of rec.radio.amateur.antenna From: Roger Subject: Re: sealing coax holes in outside wall Message-ID: <82ff825hutrj9r42aked488a2faasvqahu@4ax.com> References: <1149734093.836818.227270@f6g2000cwb.googlegroups.com> Date: Thu, 08 Jun 2006 02:05:09 -0400 On 7 Jun 2006 19:34:53 -0700, "George" wrote: > >Chris W wrote: >> Can anyone tell me what the official name of the putty they use to seal >> the holes you run your coax through so bugs don't crawl in the wall or >> water doesn't get in? I like to get all my hardware type items from >> mcmaster.com. I'm sure they have it, if I just know what it is called I >> can find it on their website. >> >> >> >> -- >> Chris W >> KE5GIX >> > >George >WB3HUH SAYS: > >Try DOW Chemical's "Great Stuff ", a "Tripple Expanding Polyurethane >Foam Sealant I'm surprised to see Dow with such a product when it competes with Dow Corning's compounds which are sold under the DAP as well as Dow Corning names. >This comes in a paint spray size can and is applied withan attachable >tube. >It sticks to everything, as it goes in as a liquid then expands to fill >even large holes. >It firms up and seals tight. Cable companies around here use it. Even >works well on cinder block > The various forms of expandable foam are easier to use, and to me work far better than the putty and self vulcanizing tape. The Silastic RTVs (TM) work well, but may be a bear to get out. Roger Halstead (K8RI & ARRL life member) (N833R, S# CD-2 Worlds oldest Debonair) www.rogerhalstead.com > > >> Gift Giving Made Easy >> Get the gifts you want & >> give the gifts they want >> One stop wish list for any gift, >> from anywhere, for any occasion! >> http://thewishzone.com Article: 225084 of rec.radio.amateur.antenna From: kretko Subject: impedance Date: Thu, 08 Jun 2006 08:48:46 +0200 Message-ID: Hello ! Im looking for a formula impedance of conductor between two ground plane. _________ * h1 * p * h2 * _________ p -conductor h1 = h2 Thank you for your help ! Goodlack ! ! ! Article: 225085 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Message-ID: <077g82l0l7crfa52216an302bqf7icaiql@4ax.com> References: Date: Thu, 08 Jun 2006 12:56:49 GMT No. I know a fellow who works in Tech support for a big computer company who says they get questions likes this all the time. There are several reasons the product has failed to meet your expectations. 1- you have likely installed it upside down. 2- Your antenna is defective, the product is not meant to be used with a defective antenna. 3- Exposure to weather has nullified your warranty. 4- There is an improved replacement product available and you may wish to upgrade at a special price. de W8CCW John On Wed, 07 Jun 2006 20:26:26 GMT, cq-dx@arrl.net (New Ham) wrote: >Did I get ripped off? John Ferrell W8CCW Article: 225086 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Thu, 08 Jun 2006 08:45:40 -0500 Message-ID: <128gag4l6ir25e0@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <1149724604.928282.248280@u72g2000cwu.googlegroups.com> <128ercucqikj3b0@corp.supernews.com> <1149773576.391521.292660@h76g2000cwa.googlegroups.com> John S. wrote: > > > David G. Nagel wrote: > >>John S. wrote: >> >>>Or looking for a left-handed crescent wrench and fetching a bucket of >>>prop wash. >> >>The problem with this joke is that the wrench exhists. Handedness in a >>wrench is determined by which thumb closes the jaws. Right thumb right >>hand wrench, left thumb left handed wrench. >> >>I have a left handed crescent type wrench. Where was it made? >>POLAND of course. >> >>Wrench available for inspection. >> > > > You had me going there for a moment..... > > I know...one side is labeled L and the flip side is labeled R. > No. This is an honest to god left handed crescent style wrench. Hold in left hand and close the jaws using the left thumb. Dave WD9BDZ Article: 225087 of rec.radio.amateur.antenna From: wood@itd.nrl.navy.mil (J. B. Wood) Subject: Re: measurements at the antenna Date: Thu, 08 Jun 2006 12:24:05 -0400 Message-ID: References: In article , dansawyeror wrote: > Good morning, > > This question is: Taking measurements at the antenna and what they mean? > > The antenna is a loaded vertical over a set of untuned radials. The feed is 50 > Ohm coax with a 1:1 isolation transformer at the antenna. I intend to run a > separate coax for measurement purposes to the feed point, stimulate the antenna > with a 10 mw signal at the operating frequency, and measure the voltage across > the antenna feed and the ground connection. > > Will the voltages indicate the relative RF impedance of antenna (including > loading coil) versus the ground? If the ground were near perfect the voltage at > the feedpoint should be close to zero. These voltages should indicate the power > disapation difference between the antenna and the ground. > > Thanks, > Dan Hello, Dan. If we have a quarter wavelength monopole the voltage at the feedpoint is at a minimum but definitely not zero even if we had a perfectly electrically conducting (PEC) ground. If we had a PEC ground and a monopole with no resistive (ohmic) losses then the impedance seen at the feedpoint at resonance would be about 37 ohms resistive. The 37 ohms is the radiation resistance of the antenna. This is where the RF power gets "dissipated" when that power is radiated into free space. If we use an electrically short antenna and put in say, a loading coil at the feedpoint to resonate the monopole at the desired frequency, we are looking at a radiation resistance of less than 37 ohms. It could be quite small depending on how short the antenna is. If in addition we have finite losses in the monopole structure, loading coil and in the ground/radials, we are measuring a resistance that is the sum of all ohmic losses and radiation resistance. And that's a classic problem - how to separate out all these losses. Without making radiation pattern measurements (to obtain total power radiated) about all you can do is calculate the radiation resistance for a PEC monopole fed against a PEC ground (or use an electromagnetics computation program like NEC to model the structure.). The measured value less the calculated radiation resistance would reflect the ohmic losses. And you still don't know how much of this is ground loss without knowledge of the other ohmic losses. There exits another direct measurement technique (Wheeler Cap) for determing antenna efficiency that can be readily applied to antennas in the GHz range but is not practical at HF because of the scaling factor (compare the size of 2.4 GHz yagi or log-periodic with the same type at 14 MHz to put things in perspective). Sincerely, John Wood (Code 5550) e-mail: wood@itd.nrl.navy.mil Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337 Article: 225088 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: sealing coax holes in outside wall References: <1149734093.836818.227270@f6g2000cwb.googlegroups.com> <82ff825hutrj9r42aked488a2faasvqahu@4ax.com> Message-ID: Date: Thu, 08 Jun 2006 16:30:08 GMT Roger wrote: > > > The various forms of expandable foam are easier to use, and to me work > far better than the putty and self vulcanizing tape. The Silastic > RTVs (TM) work well, but may be a bear to get out. > > Roger Halstead (K8RI & ARRL life member) > (N833R, S# CD-2 Worlds oldest Debonair) > www.rogerhalstead.com Altho, these may be easier to use than dux seal, beware- if the stuff smells like Vinagar (as in Ascetic acid) , you may be contaminateing your coax, as is my understanding. And, MOST RTV's have this feature (contaminateing your coax)! Not a good situation! as info, Jim NN7K Article: 225089 of rec.radio.amateur.antenna From: gene@csl.uiuc.edu (Gene Gardner) Subject: Re: measurements at the antenna Date: Thu, 8 Jun 2006 18:28:06 +0000 (UTC) Message-ID: References: ...........some "seat-of-the-pants" observations (to use an old aviator expression): To judge the performances of two similar-sized mobile installations, note the value of the shunt-C required across the feed-coax to provide good SWR 50 ohm match (or shunt-L if that option is used). The more C required (less capacitive reactance), the better [or similarly, the less L (less inductive reactance), the better]. This method of match is actually a version of the classic "L-match" where the mobile whip with its loading coil represents either R in series with Inductance, OR R in series with Capacitance at the feedpoint....depending on whether the loading coil is tuned slightly Below, or Above the resonant frequency. The shunt C (or L) is the third element in the L-Match Equation. (Many readers will already know this) Since standard antenna equations calculate the actual radiation resistance to be very small in electrically- short mobile antennas, we know that with a perfect ground, and zero-loss mast and coil, the feed-point resistance would be only the radiation resistance of a few ohms, perhaps 2 to 5 (W8JI's web page calculates a 15 ft. antenna on 1.8 MHz to be only 1.22 ohms). Therefore, if the mobile feedpoint was found to have low SWR 50 ohm match with no shunt element, that would be very bad news........it would mean that perhaps 2 parts out of 50 were radiated, and the other 48 parts were loss! And of course, here no shunt C (or L) would be required which is the worst news. Conversely, back to "seat-of-the-pants thinking", the more C (or smaller L) required, the smaller the feed-point impedance had to have been....meaning less loss resistance included at the feedpoint. Article: 225090 of rec.radio.amateur.antenna From: "Jimmie D" References: <1149734093.836818.227270@f6g2000cwb.googlegroups.com> <82ff825hutrj9r42aked488a2faasvqahu@4ax.com> Subject: Re: sealing coax holes in outside wall Message-ID: Date: Thu, 8 Jun 2006 15:58:48 -0400 "Jim - NN7K" wrote in message news:kgYhg.42344$fb2.11559@newssvr27.news.prodigy.net... > > > Roger wrote: >> >> >> The various forms of expandable foam are easier to use, and to me work >> far better than the putty and self vulcanizing tape. The Silastic >> RTVs (TM) work well, but may be a bear to get out. Roger Halstead (K8RI >> & ARRL life member) >> (N833R, S# CD-2 Worlds oldest Debonair) >> www.rogerhalstead.com > > Altho, these may be easier to use than dux seal, beware- if the stuff > smells like Vinagar (as in > Ascetic acid) , you may be contaminateing your coax, as is my > understanding. And, MOST RTV's > have this feature (contaminateing your coax)! > Not a good situation! as info, Jim NN7K Not usually a problem when going through a wall unless the outer insulation is broken, but RTV is not may favorite for this. Plain old caulk works great unless you have a big void to fill. Article: 225091 of rec.radio.amateur.antenna From: Roger Subject: Re: sealing coax holes in outside wall Message-ID: References: <1149734093.836818.227270@f6g2000cwb.googlegroups.com> <82ff825hutrj9r42aked488a2faasvqahu@4ax.com> Date: Thu, 08 Jun 2006 17:13:19 -0400 On Thu, 08 Jun 2006 16:30:08 GMT, Jim - NN7K wrote: > > >Roger wrote: >> >> >> The various forms of expandable foam are easier to use, and to me work >> far better than the putty and self vulcanizing tape. The Silastic >> RTVs (TM) work well, but may be a bear to get out. >> >> Roger Halstead (K8RI & ARRL life member) >> (N833R, S# CD-2 Worlds oldest Debonair) >> www.rogerhalstead.com > >Altho, these may be easier to use than dux seal, >beware- if the stuff smells like Vinagar (as in >Ascetic acid) , you may be contaminateing your >coax, as is my understanding. And, MOST RTV's >have this feature (contaminateing your coax)! >Not a good situation! as info, Jim NN7K Jimmie already go this one, but if the seal is pretty much out in the open it will not contaminate the coax jacket. Normally the stuff won't bother the jacket any way, just don't apply directly to copper or aluminum braid as the Copper will turn green. OTOH there are versions available in Silicon that are non-contaminating and there are also latex/water based versions. Most of the DAP (TM) ( made by DC) is water based although you can specify Silicon. Once cured there is not a great deal of difference although there are some. Roger Halstead (K8RI & ARRL life member) (N833R, S# CD-2 Worlds oldest Debonair) www.rogerhalstead.com Article: 225092 of rec.radio.amateur.antenna From: cq-dx@arrl.net (New Ham) Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Message-ID: References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> Date: Thu, 08 Jun 2006 21:18:31 GMT In article <1149774341.518961.129650@i40g2000cwc.googlegroups.com>, "John S." wrote: > >jawod wrote: >> John S. wrote: >> > New Ham wrote: >> > >> >>Did I get ripped off? >> > >> > >> > You might try a Stetson. >> > >> Try a Dunce Cap (low capacitance) attached to your screwdriver and >> manually adjust until your dip meter reads moron :) > >Uh oh...feeling a bit testy today??? What good's a hat if it don't keep the antenna dry? I think I'll keep it though, for some odd reason my SWR's are better. Article: 225093 of rec.radio.amateur.antenna Message-ID: <44889424.5070305@fuse.net> Date: Thu, 08 Jun 2006 17:18:28 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> John S. wrote: > jawod wrote: > >>John S. wrote: >> >>>New Ham wrote: >>> >>> >>>>Did I get ripped off? >>> >>> >>>You might try a Stetson. >>> >> >>Try a Dunce Cap (low capacitance) attached to your screwdriver and >>manually adjust until your dip meter reads moron :) > > > Uh oh...feeling a bit testy today??? > Not, not at all...didn't you see my :) ? No offense intended. Article: 225094 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: measurements at the antenna Message-ID: <3t4h82p7805tv1vqaq7hqcbturep8s49hc@4ax.com> References: Date: Thu, 08 Jun 2006 21:26:48 GMT On Thu, 08 Jun 2006 07:03:05 -0700, dansawyeror wrote: >Ohm coax with a 1:1 isolation transformer at the antenna. I intend to run a >separate coax for measurement purposes to the feed point, stimulate the antenna >with a 10 mw signal at the operating frequency, and measure the voltage across >the antenna feed and the ground connection. You seem to be implying more than one measurement, and that with those measurements you can separately determine (radiation resistance + loss resistance in the vertical and coil) and loss resistance in the ground system. Can you elaborate? Perhaps a block diagram of your measurement setup might reveal what you are thinking. (If you need a tool for drawing schematics in ascii text, Google for AACircuit. Alternatively, sketch it, scan it and publish it on a web site somewhere... DON'T attach it to your news post.) Owen -- Article: 225095 of rec.radio.amateur.antenna From: "W.Henry" Subject: 3 Killed in Fall From Iowa TV Tower Message-ID: Date: Thu, 08 Jun 2006 21:38:16 GMT 3 Killed in Fall From Iowa TV Tower Jun 01 http://www.breitbart.com/news/2006/06/01/D8HV79B00.html OAKLAND, Iowa Three workers fell 1,100 feet Wednesday from an Iowa Public Television tower and died, officials said. Bill Hayes, director for engineering at IPTV, said the crew was replacing strobe lights when the accident happened. "They were up fairly high when something went wrong and all three members of the crew fell," Hayes said. "We don't know what the actual cause was." He said a fourth member of the crew was working on the ground, operating a winch, hoisting parts to the crew. "We can only assume that the safety equipment failed," said Pottawattamie County Sheriff Jeff Danker. The men _ ages 57, 27 and 19 _ were pronounced dead at the scene. They worked for Deter Tower Service, of Grimes. Their names weren't immediately released. A woman answering the phone at Deters said no one was available to talk about the accident. She declined further comment. -- Humble to the humble , inflexible to the arrogant . begin 666 dot_clear.gif K1TE&.#EA`0`!`( ``/___P```"'Y! $`````+ `````!``$```("1 $`.P`` ` end Article: 225096 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Thu, 08 Jun 2006 16:46:03 -0500 Message-ID: <128h6krkcmme48c@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <1149724604.928282.248280@u72g2000cwu.googlegroups.com> <128ercucqikj3b0@corp.supernews.com> <1149774179.543305.288650@f6g2000cwb.googlegroups.com> John S. wrote: > Brian Denley wrote: > >>David G. Nagel wrote: >> >>>John S. wrote: >>> >>>>Or looking for a left-handed crescent wrench and fetching a bucket of >>>>prop wash. >>> >>>The problem with this joke is that the wrench exhists. Handedness in a >>>wrench is determined by which thumb closes the jaws. Right thumb right >>>hand wrench, left thumb left handed wrench. >>> >>>I have a left handed crescent type wrench. Where was it made? >>>POLAND of course. >>> >>>Wrench available for inspection. >>> >>>Dave WD9BDZ >>> >>> >> >>At 23, I took a job as a young engineer at a place that had previously been >>a gyroscope manufacturer. As the new guy, they asked my to deliver a >>briefcase to the boss' office and (you guessed it) there was a spinning gryo >>in the briefcase. I got a big surprise when I tried to turn a corner in the >>corrider and the briefcase kept going straight ahead! A great 'new guy' >>trick. >>-- > > > > Or send the new guy in engineering to supply for a pressurized > container of Dihydrogen Monoxide. > Careful that stuff is extremely deadly if inhaled. > Or send the new finance guy to get the difference finder. > Article: 225097 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Thu, 08 Jun 2006 16:47:11 -0500 Message-ID: <128h6n0a56nj295@corp.supernews.com> References: <9LWhg.13749$523.13324@trnddc07> Reloader wrote: > John - KD5YI Wrote: > >>New Ham wrote: >>Did I get ripped off? >> >> >> >>Old Office supply joke. Goo get the paper stetcher. But I answered, >>you want the one in the maintenance shop or the one in Mr. Anderaon's >>(the owner's) Office. They VERY QUICKLY told me it was a joke. I told >>them, "I know." Hated me ever since. > > > Why do you hate yourself? Article: 225098 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Thu, 08 Jun 2006 22:25:41 GMT On 8 Jun 2006 05:42:37 -0700, Mystery.DXer@yahoo.com wrote: >Buyer Beware Hmmm. >same antenna I purchased. I bought the Cobra junior antenna and >followed the directions for installation. The antenna is 50ft in the >air in a flat top configuration. When I hooked it up to my radio, it >would not tune on segments of certain bands, most noticeably 75/80. I >called Joe to get some help and was told that my radio, which has a >built in tuner would not accept more than a certain level of SWR and >was told to trim the twinlead back 19 feet. I did and while some of the >problem was solved, I continued to have problems on 75/80. I emailed >Joe to ask for further assistance and was told that the next step was >to buy a tuner extender (price $60). Not the answer I wanted to hear. >If in fact this kind of problem exists with radios that have built in >tuners, prospective buyers should know that in advance. For the cost of >the antenna and now the tuner extender, I could have bought a better >antenna, which is what I intend to do. I am not pleased with this >antenna and would not recommend it especially to someone who has a >radio with a built in tuner and intends to use it. Additionaly, the >performance on 40 seems to be very good. It seems to under perform on >20. Can't tell on 75/80 because I can't tune the band. That all seems pretty reasonable though the explanation that the "built in tuner would not accept more than a certain level of SWR" is not a good way to express the limits of internal tuners, but it is an explanation that would appeal to those with lesser knowledge. Well, it looks like you have learned something that many of us know, that the internal tuner in most radios has quite limited range and is really for minor trimming of loads to enable the radio to develop rated power (not to mention poor efficiency on the lowest bands). Joe advertises honestly that the antenna will need a tuner for operation on any frequency, perhaps he needs to spell out that what manufacturers fit into a corner of a transceiver may not be up to the task. Frankly, I am wondering why your beef isn't equally with the transceiver manufacturer for deceiving you with a tuner that isn't up to the task. I wonder what "better antenna" you have in mind? The short multiband HF antenna that has low SWR(50) on all bands (since you have an issue with tuners) and good performance is the holy grail of HF amateurs that will provide you with challenge for the years ahead. To some extent, the residual technical content in amateur radio is mating up system components that are compatible to form a working station. Owen -- Article: 225099 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Give up CB for ham? Date: Thu, 08 Jun 2006 15:43:18 -0700 Message-ID: References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> ORIGINAL MESSAGE: On Tue, 6 Jun 2006 09:36:21 -0400, "clfe" wrote: >I am of the opinion that a 5 WPM at least - should be kept on as a >requirement - as someday - it may be needed. Think not? Say you're in the >midst of an attack - of terrorism, a war on our homefront OR a large scale >natural disaster, a microphone isn't working or available. You can key the >radio but don't know code - now what? With code, even at 5 WPM - you could >get some very important information to those needing it to help save you - >to them. You could tell them WITH code, what is needed, exact whereabouts, >how many people involved, etc........ Just clicking a mic pin with a wire >won't tell anyone anything and could delay any help or a response big enough >to do much good. In these times with the large scale disasters as we've seen >and attacks - even for any said to be planned, NOW is a good time to WANT to >know code. IT may save you........ It is one of those skills you learn - >just like CPR or whatever - you hope you never have to use, but you're glad >you have it - when you need it. *********** REPLY SEPARATOR *********** Your priorities are skewed. Since there are only so many hours allotted to us, what would be a better way to spend your spare time: 1. Learning morse code for the above mike-failure scenario? 2. Stocking up food, water and ammo for the above mike-failure scenario? You have been reading too many stories of the valiant radio op on the Titanic. Ain't gonna happen. Bill, W6WRT 20 wpm Extra, but realistic about it Article: 225100 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Give up CB for ham? Date: Thu, 08 Jun 2006 15:45:28 -0700 Message-ID: References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <44858906$0$3702$ecde5a14@news.coretel.net> ORIGINAL MESSAGE: On Tue, 6 Jun 2006 09:54:14 -0400, "clfe" wrote: >One other thing........ I cut my teeth on CB back when the FCC was busting >CBers regularly for violations. I then got into Ham and Electronics. *********** REPLY SEPARATOR *********** Your CB origin is showing. "Ham" is an adjective, not a noun. One does not "get into ham", one "gets into ham radio". 10-4? Bill, W6WRT Article: 225101 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> Message-ID: Date: Thu, 08 Jun 2006 23:07:25 GMT Bill Turner wrote: > You have been reading too many stories of the valiant radio op on the > Titanic. Ain't gonna happen. Seems the bullies are not all on SSB after all. Didn't the Titanic's CW operator bully the California's CW operator to such an extent that he turned off, turned in, and the rest is history? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225102 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <44858906$0$3702$ecde5a14@news.coretel.net> Message-ID: Date: Thu, 08 Jun 2006 23:08:38 GMT Bill Turner wrote: > "Ham" is an adjective, not a noun. Are you a ham? :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 225103 of rec.radio.amateur.antenna Message-ID: <4488B7B0.2000303@fuse.net> Date: Thu, 08 Jun 2006 19:50:08 -0400 From: jawod Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <44858906$0$3702$ecde5a14@news.coretel.net> > > Your CB origin is showing. "Ham" is an adjective, not a noun. One does > not "get into ham", one "gets into ham radio". > > 10-4? > > Bill, W6WRT > Gee, Bill. That's mighty specific. But since you brought it up. "Ham" can be used as a proper noun: "I'm a Ham". Not everyone goes to the trouble of saying "ham radio operator". It's also a sandwich. Article: 225104 of rec.radio.amateur.antenna Message-ID: <4488B859.1050108@fuse.net> Date: Thu, 08 Jun 2006 19:52:57 -0400 From: jawod Subject: Re: Have any of you mailed this to your ARRL Division directors and References: <6i2ig.3313$o4.2436@newsread2.news.pas.earthlink.net> > > I just knew none of you would take this serious and help. I bet you're > all democrats. > > sc Nope, Communist. Every damn one of us. Join us, comrade! Article: 225105 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Fri, 09 Jun 2006 00:59:53 GMT On Thu, 08 Jun 2006 20:33:12 -0400, Mike Coslo wrote: > I'd buy a tuner that will handle open wire feed, lose the 4:1 balun, >and get on the air. Mike, did you notice "Mystery's" comment re spending more money on a "tuner extender": "Not the answer I wanted to hear". She/he may be even less interested in the spend on the tuner you describe. I agree with you that antenna looks worth a try / perseverance, but it will probably need a wider range tuner than commonly fitted internal to transceivers unless you experiment (what's that!) to find a feedline length that the rig/runer accommodates on all bands, or switch feedline lengths. Owen -- Article: 225106 of rec.radio.amateur.antenna From: "clfe" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> Subject: Re: Give up CB for ham? Date: Thu, 8 Jun 2006 21:29:02 -0400 Message-ID: <4488ced6$0$3683$ecde5a14@news.coretel.net> "Bill Turner" wrote in message news:co9h82d7fejjh7ac87n63pe9lgkcuu1120@4ax.com... > ORIGINAL MESSAGE: > > On Tue, 6 Jun 2006 09:36:21 -0400, "clfe" wrote: > > >>I am of the opinion that a 5 WPM at least - should be kept on as a >>requirement - as someday - it may be needed. Think not? Say you're in the >>midst of an attack - of terrorism, a war on our homefront OR a large scale >>natural disaster, a microphone isn't working or available. You can key the >>radio but don't know code - now what? With code, even at 5 WPM - you could >>get some very important information to those needing it to help save you - >>to them. You could tell them WITH code, what is needed, exact whereabouts, >>how many people involved, etc........ Just clicking a mic pin with a wire >>won't tell anyone anything and could delay any help or a response big >>enough >>to do much good. In these times with the large scale disasters as we've >>seen >>and attacks - even for any said to be planned, NOW is a good time to WANT >>to >>know code. IT may save you........ It is one of those skills you learn - >>just like CPR or whatever - you hope you never have to use, but you're >>glad >>you have it - when you need it. > > *********** REPLY SEPARATOR *********** > > Your priorities are skewed. Since there are only so many hours > allotted to us, what would be a better way to spend your spare time: > > 1. Learning morse code for the above mike-failure scenario? > 2. Stocking up food, water and ammo for the above mike-failure > scenario? > > You have been reading too many stories of the valiant radio op on the > Titanic. Ain't gonna happen. > > Bill, W6WRT > 20 wpm Extra, but realistic about it > > Not really, but I'm not in a mood to argue about stupid shit - anymore. Actually, I could care less. My ham days are few and far in between due to all the ass holes on there ruining it for the rest of us. Maybe you're right.......... the code really didn't keep the crud off the radios. Hell, why even have a test at all. Article: 225107 of rec.radio.amateur.antenna From: "clfe" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <44858906$0$3702$ecde5a14@news.coretel.net> Subject: Re: Give up CB for ham? Date: Thu, 8 Jun 2006 21:30:17 -0400 Message-ID: <4488cf20$0$3686$ecde5a14@news.coretel.net> "Bill Turner" wrote in message news:i1ah82tjdddgjjvcsknsdnajpf5qmg40cs@4ax.com... > ORIGINAL MESSAGE: > > On Tue, 6 Jun 2006 09:54:14 -0400, "clfe" wrote: > > >>One other thing........ I cut my teeth on CB back when the FCC was busting >>CBers regularly for violations. I then got into Ham and Electronics. > > *********** REPLY SEPARATOR *********** > > Your CB origin is showing. "Ham" is an adjective, not a noun. One does > not "get into ham", one "gets into ham radio". > > 10-4? > > Bill, W6WRT > For christ's sakes - a misuse of words - so what........ I'm not an English Major. If that is all you can find to run off at the mouth about, why bother? Article: 225108 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Buyer Beware - Cobra Ultralight References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <1149817448.339895.295850@u72g2000cwu.googlegroups.com> Message-ID: <3G4ig.48095$Lm5.9297@newssvr12.news.prodigy.com> Date: Fri, 09 Jun 2006 02:03:43 GMT w8ji@akorn.net wrote: > The problem is that antenna is advertised to work all bands. > Unfortunately it doesn't do very well on many bands. Sounds like a G5RV. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225109 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: Buyer Beware - Cobra Ultralight Date: Fri, 09 Jun 2006 02:15:36 -0000 Message-ID: <128hme8sbfdeoe6@corp.supernews.com> References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <1149817448.339895.295850@u72g2000cwu.googlegroups.com> >> >same antenna I purchased. I bought the Cobra junior antenna and >> >followed the directions for installation. The antenna is 50ft in the >> >air in a flat top configuration. When I hooked it up to my radio, it >> >would not tune on segments of certain bands, most noticeably 75/80. I > >> That all seems pretty reasonable though the explanation that the >> "built in tuner would not accept more than a certain level of SWR" is >> not a good way to express the limits of internal tuners, but it is an >> explanation that would appeal to those with lesser knowledge. > >The problem is that antenna is advertised to work all bands. >Unfortunately it doesn't do very well on many bands. > >The SWR is "off the scale" on many bands. The same would be true of almost any other doublet-style antenna, I think. Such antennas are often usable on a large number of bands if you have a wide-range transmatch/tuner, but I don't think I know of any which are usable in this way with the limited-matching-range "line flattener" ATUs built into modern solid-state transceivers. The Cobra Ultralight is only about 60% as long as a normal resonant near-half-wave dipole for 75/80 meters. It's shortened by linear loading. I imagine it has a narrower SWR bandwidth than a simple dipole. The manufacturer states that a tuner _is_ required. The wording is perhaps somewhat more optimistic about using a transceiver's built-in ATU than is justified, though. I wouldn't plan to use an antenna of this sort without a good external tuner with balanced-output capability (whether intrinsic or via a good current balun). The original poster might want to consider making a multi-wire (or "fan") dipole. With several sets of wires it'd surely be possible to make one which would tune on 80, 75, 40, and 20 well enough to not need an external tuner... although fitting it into under 80 feet of linear space might prove to be a challenge. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 225110 of rec.radio.amateur.antenna From: "Jerry" References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: Date: Thu, 8 Jun 2006 22:38:40 -0400 wrote in message news:1149770557.629987.141180@i40g2000cwc.googlegroups.com... > Buyer Beware > I have read all the reviews and I am wondering if they are about the > same antenna I purchased. I bought the Cobra junior antenna and > followed the directions for installation. The antenna is 50ft in the > air in a flat top configuration. When I hooked it up to my radio, it > would not tune on segments of certain bands, most noticeably 75/80. I > called Joe to get some help and was told that my radio, which has a > built in tuner would not accept more than a certain level of SWR and > was told to trim the twinlead back 19 feet. I did and while some of the > problem was solved, I continued to have problems on 75/80. I emailed > Joe to ask for further assistance and was told that the next step was > to buy a tuner extender (price $60). Not the answer I wanted to hear. > If in fact this kind of problem exists with radios that have built in > tuners, prospective buyers should know that in advance. For the cost of > the antenna and now the tuner extender, I could have bought a better > antenna, which is what I intend to do. I am not pleased with this > antenna and would not recommend it especially to someone who has a > radio with a built in tuner and intends to use it. Additionaly, the > performance on 40 seems to be very good. It seems to under perform on > 20. Can't tell on 75/80 because I can't tune the band. > > KC2GWK Lots could be wrong here including trying to kibbutz the problem from afar. But it *sounds* like it is a combination of not enough tuner and a "bit" of operator error. The internal tuners simply do not have enough capacity to meet the demands of all-band operation in some cases. I have the Ultralite Senior using the LDG Pro 100 tuner and I simply LOVE this antenna! I know that there is loss on some bands, but any so-called "all-band" antenna is going to be a compromise when compared to a dedicated, resonant antenna. I don't even LIKE tuners, but I have some requirements beyond the Amateur bands including US gov't SHARES and FEMA. I have to quickly move from one band to the other and, in order to do so, I have to accept some loss. However, I am VERY happy and surprised at the overall performance of *my* antenna. Actually, I'm told that it is unusually loud for a 100 watt station on a number of bands and quite readable on others (I don't HAVE to be the loudest thing going to be effective). I would guess----and that is what it is, a guess------that your internal tuner doesn't have the ability to match this antenna-----AND probably a number of others as well in multi-band service. Or you simply may have overlooked something in the installation---like location or height above ground. For every 10 users of a product, there's going to be one, perhaps, that is dissatisfied. With the Cobra, the reviews I have read are decidedly in favor of both the Junior AND the Senior Ultralight. You can't win 'em all! 73 K4KWH > Article: 225111 of rec.radio.amateur.antenna Date: Thu, 08 Jun 2006 22:30:01 -0500 From: Tom Ring Subject: Re: Have any of you mailed this to your ARRL Division directors and References: <6i2ig.3313$o4.2436@newsread2.news.pas.earthlink.net> Message-ID: <4488eb3a$0$1006$39cecf19@news.twtelecom.net> Slow Code wrote: > > > > I just knew none of you would take this serious and help. I bet you're > all democrats. > > sc Wrongo smart guy. And I only take things seriously that deserve it. tom K0TAR Article: 225112 of rec.radio.amateur.antenna Date: Thu, 08 Jun 2006 22:34:42 -0500 From: Tom Ring Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4488ced6$0$3683$ecde5a14@news.coretel.net> Message-ID: <4488ec52$0$6141$39cecf19@news.twtelecom.net> clfe wrote: > Not really, but I'm not in a mood to argue about stupid shit - anymore. > Actually, I could care less. My ham days are few and far in between due to > all the ass holes on there ruining it for the rest of us. Maybe you're > right.......... the code really didn't keep the crud off the radios. Hell, > why even have a test at all. > > > Time to hang up your ticket I guess. We are all assholes, and you are the only "true ham radio operator" left. Go play with yourself. tom K0TAR Article: 225113 of rec.radio.amateur.antenna Date: Thu, 08 Jun 2006 22:37:14 -0500 From: Tom Ring Subject: Re: Give up CB for ham? References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4488ced6$0$3683$ecde5a14@news.coretel.net> Message-ID: <4488ecea$0$6141$39cecf19@news.twtelecom.net> clfe wrote: > Not really, but I'm not in a mood to argue about stupid shit - anymore. > Actually, I could care less. My ham days are few and far in between due to > all the ass holes on there ruining it for the rest of us. Maybe you're > right.......... the code really didn't keep the crud off the radios. Hell, > why even have a test at all. > And at least we admit who we are. You, on the other hand, are hiding. You are likely just a frigging troll that isn't even licensed. tom K0TAR Article: 225114 of rec.radio.amateur.antenna From: Buck Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Fri, 09 Jun 2006 00:05:47 -0400 On Fri, 09 Jun 2006 00:59:53 GMT, Owen Duffy wrote: >On Thu, 08 Jun 2006 20:33:12 -0400, Mike Coslo > wrote: > > >> I'd buy a tuner that will handle open wire feed, lose the 4:1 balun, >>and get on the air. > >Mike, did you notice "Mystery's" comment re spending more money on a >"tuner extender": "Not the answer I wanted to hear". She/he may be >even less interested in the spend on the tuner you describe. > >I agree with you that antenna looks worth a try / perseverance, but it >will probably need a wider range tuner than commonly fitted internal >to transceivers unless you experiment (what's that!) to find a >feedline length that the rig/runer accommodates on all bands, or >switch feedline lengths. > >Owen There really isn't a lot of information on the antenna on the page I saw: http://www.k1jek.com/. Many antennas have a spectrum of frequencies and their associated SWR. Knowing my internal tuner can only handle 8:1 but the antenna shows places I am interested in using with 12:1, would help me in my decision to choose the antenna or another. the OP didn't have that information. I know that internal antenna tuners are basically 'fine-tuners' and are very limited compared to external tuners. (at least Kenwood is clear about that in their instruction guides. ) I am not pointing a finger at either party, Mystery for not posting the information or some warning nor the OP for not asking. The Mystery page isn't very Corporate looking so one would have to assume some give and take in the purchase by both parties. Is there any reason the antenna can't be returned for a refund? If not, can it be sold to someone else who is interested? This is one of life's lessons learned. I just looked at the review of the antenna from eHam.com: =============== WA1BSB Rating: 5/5 Apr 24, 2006 14:29 Homemade Ultrilite Senior Time owned: 0 to 3 months Hi I went and made a homemade Ultrilite I too 3 conductor tv rotor cable 70 ft each side and mounted it to a modified 450 ohm ladderloc at the center I then ran about 50 ft of ladder line down to a 4.1 balun I know the plan calls for 100 ft but I just dint have the spot to coil it up The antenna is in a flat top configuration up between 2 trees about 80 ft up from the balun I ran about 70 ft of RG8X 50 ohm to my 746 Pro it tunes perfect on all bands 10-160 using the radios tuner 1.1 swr Anyhow it works with good signal reports so far on 40 and 20 meter Im looking forward to trying in 75 and 160 Anyhow bottom line whether you make one or buy it its quite the antenna I glad I got one 73s ================== There are many other reviews about the antennas, both jr and sr. Maybe there is a better configuration that will work, or he may need the tuner or tuner extender. Good luck Buck -- 73 for now Buck N4PGW Article: 225115 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: H FIELD ANTENNAS? References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> <128dh45bejvrd5d@corp.supernews.com> <1149721730.564878.262550@j55g2000cwa.googlegroups.com> <128f0bfir75r9ec@corp.supernews.com> <1149737733.436349.216110@f6g2000cwb.googlegroups.com> <1149769611.319099.279910@j55g2000cwa.googlegroups.com> <1149819131.652479.124510@j55g2000cwa.googlegroups.com> Message-ID: Date: Fri, 09 Jun 2006 04:06:36 GMT w8ji@akorn.net wrote: > Now I'm not saying wind, dust, and moisture blowing across a > well-insulated antenna won't charge it faster, and make an antenna > without a ground path leak arc over some close gap more rapidly. I cured the problem by going to 1000v insulation on the antenna wire. 600v insulation didn't cure the problem. > I'm only saying I never have seen the noise pitch of what people > commonly call P-static track the actual number of droplets or dust > hitting the antenna, ... Uhhhh Tom, it doesn't happen in Georgia just as it doesn't happen in East Texas. If I had never lived in Queen Creek, Arizona, I never would have seen it either. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225116 of rec.radio.amateur.antenna From: "Ed" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> Subject: Re: Give up CB for ham? Message-ID: Date: Fri, 09 Jun 2006 04:55:44 GMT Give up CB for Ham.....what the hell would you be giving up? "Bill Turner" wrote in message news:co9h82d7fejjh7ac87n63pe9lgkcuu1120@4ax.com... > ORIGINAL MESSAGE: > > On Tue, 6 Jun 2006 09:36:21 -0400, "clfe" wrote: > > >>I am of the opinion that a 5 WPM at least - should be kept on as a >>requirement - as someday - it may be needed. Think not? Say you're in the >>midst of an attack - of terrorism, a war on our homefront OR a large scale >>natural disaster, a microphone isn't working or available. You can key the >>radio but don't know code - now what? With code, even at 5 WPM - you could >>get some very important information to those needing it to help save you - >>to them. You could tell them WITH code, what is needed, exact whereabouts, >>how many people involved, etc........ Just clicking a mic pin with a wire >>won't tell anyone anything and could delay any help or a response big >>enough >>to do much good. In these times with the large scale disasters as we've >>seen >>and attacks - even for any said to be planned, NOW is a good time to WANT >>to >>know code. IT may save you........ It is one of those skills you learn - >>just like CPR or whatever - you hope you never have to use, but you're >>glad >>you have it - when you need it. > > *********** REPLY SEPARATOR *********** > > Your priorities are skewed. Since there are only so many hours > allotted to us, what would be a better way to spend your spare time: > > 1. Learning morse code for the above mike-failure scenario? > 2. Stocking up food, water and ammo for the above mike-failure > scenario? > > You have been reading too many stories of the valiant radio op on the > Titanic. Ain't gonna happen. > > Bill, W6WRT > 20 wpm Extra, but realistic about it > > Article: 225117 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Fri, 09 Jun 2006 05:13:04 GMT On Fri, 09 Jun 2006 00:05:47 -0400, Buck wrote: >frequencies and their associated SWR. Knowing my internal tuner can >only handle 8:1 but the antenna shows places I am interested in using Buck, how do you know that your tuner can handle (presumably SWR up to) 8:1? Is it a commonly published specification for transceiver internal tuners or external tuners? The capability of a tuner is much more complex (pardon the pun), but could be mapped for each band to a Smith Chart as an area of input Z that could be transformed to 50 ohms, and then one could plot loss contours to show the acceptable range. What would you do with the information? Whilst it may be appropriate to specify the tolerance of Z on a nominal 50 ohms antenna with a maximum VSWR in a given frequency range (eg as often done for VHF and UHF antennas), the Cobra does not pretend to present any particular impedance on any particular frequency (remember that user is permitted to use any length of open wire feed operating at high VSWR, so the Z at the tx end of the balun cannot be specified at any frequency). The Cobra Junior, a 72' long linear loaded dipole, looks interesting in terms of a short antenna for low HF bands with reasonably low losses. I have run some preliminary NEC models and analysed the feed system loss with 25m of W551 ladder line, they look promising. I will build a complete model over HF along the lines of the ones that underly my article on the G5RV feed system at http://www.vk1od.net/G5RV/index.htm . More when it is done in a day or three. Owen -- Article: 225118 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: RF grounding methods for sailboats: A Summary Date: Thu, 08 Jun 2006 23:08:08 -0700 Message-ID: <128i42c75ciau8f@corp.supernews.com> References: <1148994725_36063@sp6iad.superfeed.net> <6ggr72509n8k0ulii7a3j574e6ogiuhrbp@4ax.com> <1149107678_2377@sp6iad.superfeed.net> <447ec69c_1@news.iprimus.com.au> <128278grmhthsab@corp.supernews.com> <1288u8idqtf9b0a@corp.supernews.com> Mike Coslo wrote: > Roy Lewallen wrote: >>. . . >> What will cause it to vary? In any case, just make the capacitance >> large enough so the reactance is always small compared to the ground >> impedance, then it won't matter. > > Well, I could be wrong, but if one side of the capacitor is on the > inside of the hull, and the other side is the sea water, is not the > motion of the ship going to affect that? ships move up and down quite a > bit, and low draft ones can have a *lot* of that hull out of the water, > and then a few seconds later have water coming over the bow. Well, I was envisioning a plate on some part of the hull which always had water on the other side. If the hull on the other side of the plate comes out of the water, you'll of course effectively lose coupling to the water from that part of the plate. But again, if you make the plate large enough so that enough of the plate always has water on the other side of the hull to make a low impedance, the variation won't matter. Sounds like you might have to make the plate cover a fair portion of the hull to insure that there's always water on the other side of some of it. If the entire hull comes out of the water, just remember to say "mayday" really quick every time the hull hits the water. Other than that, seems to me you'll probably be too busy to be playing with the radio anyway. Roy Lewallen, W7EL Article: 225119 of rec.radio.amateur.antenna From: "clfe" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4488ced6$0$3683$ecde5a14@news.coretel.net> <4488ec52$0$6141$39cecf19@news.twtelecom.net> Subject: Re: Give up CB for ham? Date: Fri, 9 Jun 2006 03:25:33 -0400 Message-ID: <44892265$0$3702$ecde5a14@news.coretel.net> "Tom Ring" wrote in message news:4488ec52$0$6141$39cecf19@news.twtelecom.net... > clfe wrote: > >> Not really, but I'm not in a mood to argue about stupid shit - anymore. >> Actually, I could care less. My ham days are few and far in between due >> to all the ass holes on there ruining it for the rest of us. Maybe you're >> right.......... the code really didn't keep the crud off the radios. >> Hell, why even have a test at all. >> >> >> > > Time to hang up your ticket I guess. We are all assholes, and you are the > only "true ham radio operator" left. Go play with yourself. > > tom > K0TAR Nah, not all of "us" or "you" in the case of your statement. I'm just saying a lot of crap is going on - on the bands today and its not worth even earning a ticket for - anymore. Ham radio and yes, even CB - used to be respectable at one time. How times change. Its hardly worth turning on the radio anymore. Especially on say 10 and 80 meters. But back to "your" statement, there are still "many" decent operators on both the Ham AND CB bands - out there. Ya just got to pick through the rubble to find them sometimes. And NO, I"m not the "ONLY" "TRUE" Operator left........ Don't put words in my mouth, I certainly didn't place myself on any pedestal. Again - there are LOTS of decent operators out there. I didn't say "ALL" were bad - but there are - you have to admit - quite a few bad ones. Its gotten worse in the past few years. Article: 225120 of rec.radio.amateur.antenna From: "clfe" References: <1149534276.955122.310050@i40g2000cwc.googlegroups.com> <4484dc50$0$1013$39cecf19@news.twtelecom.net> <128a2tq2vmeil53@corp.supernews.com> <5isa8294s7h2n8qtlpe39amh3qna7oa4hk@4ax.com> <4485851f$0$3708$ecde5a14@news.coretel.net> <4488ced6$0$3683$ecde5a14@news.coretel.net> <4488ecea$0$6141$39cecf19@news.twtelecom.net> Subject: Re: Give up CB for ham? Date: Fri, 9 Jun 2006 03:36:46 -0400 Message-ID: <44892506$0$3706$ecde5a14@news.coretel.net> "Tom Ring" wrote in message news:4488ecea$0$6141$39cecf19@news.twtelecom.net... > clfe wrote: > >> Not really, but I'm not in a mood to argue about stupid shit - anymore. >> Actually, I could care less. My ham days are few and far in between due >> to all the ass holes on there ruining it for the rest of us. Maybe you're >> right.......... the code really didn't keep the crud off the radios. >> Hell, why even have a test at all. >> > > And at least we admit who we are. You, on the other hand, are hiding. You > are likely just a frigging troll that isn't even licensed. > > tom > K0TAR > > I don't sign with my call. Some like to - that is their choice. But even if they didn't - wouldn't give me any reason to doubt them being licensed. "Posting" a call sign doesn't prove a thing. "I" for one - am NOT going to go running to the FCC database to check your call or any other to see if it is legit. I don't care........ Article: 225121 of rec.radio.amateur.antenna From: "Jimmie D" References: Subject: Re: Yet another 6m 3el Quad question Message-ID: Date: Fri, 9 Jun 2006 04:03:46 -0400 "Ken Bessler" wrote in message news:jXDhg.37830$4H.24271@dukeread03... > My Quad is all built and I'm waiting or FedEx to deliver > my rotor. I built the quad out of wood, with a 1-1/4" dia > pine boom and 4' mast plus 1/4"x48" spruce dowels for > spreaders. I used insulated 16g stranded wire for the > elements. All the wood is either painted or treated with > sealer. > > Problem is I just broke a spreader moving the antenna and > I'm worried about how fragile the whole design is. Would > the performance change much if I used 1/4" aluminum rods > instead? Maybe I should just get some fiberglass resin and > paint the spreaders with several coats? How about wrapping > them in re-enforced boxers tape (the good stuff with fibers > in the tape)? > > Thanks for the help, guys.... > > -- > 73's de Ken KG0WX - Kadiddlehopper #11808, > Flying Pigs #-1055, Grid EM17io, FT-857D, AL-84, > Elecraft XG2, 4SQRP Tenna Dipper, Heath GD-1B > > I found 1/4 inch fiberglass a little flimsy for a 6 meter quad but workable, 3/8ths was much better. next time I build one it will probably be 1/2 inch fiberglass. Article: 225122 of rec.radio.amateur.antenna From: Butch Magee Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Fri, 09 Jun 2006 06:59:40 -0500 Message-ID: <128iolddveh4j8d@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Brian Hill wrote: > "John S." wrote in message > news:1149714609.565540.160300@c74g2000cwc.googlegroups.com... > >>New Ham wrote: >> >>>Did I get ripped off? >> >>You might try a Stetson. >> > > > four or five X beaver John? > > BH > > No, no! Thats a waste of good beaver : Article: 225123 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Buyer Beware - Cobra Ultralight References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Message-ID: Date: Fri, 09 Jun 2006 12:19:25 GMT Owen Duffy wrote: > The capability of a tuner is much more complex (pardon the pun), but > could be mapped for each band to a Smith Chart as an area of input Z > that could be transformed to 50 ohms, and then one could plot loss > contours to show the acceptable range. Here's what my IC-756PRO manual says about its internal tuner: "*Matching impedance range: HF bands, 16.7 to 150 ohms unbalanced (Less than VSWR 3:1)" -- 73, Cecil http://www.qsl.net/w5dxp Article: 225124 of rec.radio.amateur.antenna From: Buck Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Fri, 09 Jun 2006 08:25:59 -0400 On Fri, 09 Jun 2006 05:13:04 GMT, Owen Duffy wrote: >On Fri, 09 Jun 2006 00:05:47 -0400, Buck wrote: > >>frequencies and their associated SWR. Knowing my internal tuner can >>only handle 8:1 but the antenna shows places I am interested in using > >Buck, how do you know that your tuner can handle (presumably SWR up >to) 8:1? Is it a commonly published specification for transceiver >internal tuners or external tuners? In the manuals or specifications of most radios I have looked at with internal tuners, they say somewhere what the tuner can match. The Kenwood TS440SAT had in its instructions somewhere that it could match antennas with SWR up to 10:1 (which seems to be typical of most internal tuners on radios.) I have read the specs of many rigs including Yaesu, Kenwood and Icom. I can't say which have the specs and which don't, but I remember reading the specs many times for many radios. > >The capability of a tuner is much more complex (pardon the pun), but >could be mapped for each band to a Smith Chart as an area of input Z >that could be transformed to 50 ohms, and then one could plot loss >contours to show the acceptable range. What would you do with the >information? I would read the radio specs, check my antenna and if the antenna matched, it matched, if not, I would use an external tuner, adjust the antenna, replace the antenna or repair the radio if necessary. > >Whilst it may be appropriate to specify the tolerance of Z on a >nominal 50 ohms antenna with a maximum VSWR in a given frequency range >(eg as often done for VHF and UHF antennas), the Cobra does not >pretend to present any particular impedance on any particular >frequency (remember that user is permitted to use any length of open >wire feed operating at high VSWR, so the Z at the tx end of the balun >cannot be specified at any frequency). > I saw NO specifications on the antenna related to resonance when I looked (the link is posted on an earlier posting.) This leads me to believe that the antenna is made by a hobbyist rather than a professional corporation. This isn't necessarily bad, but it would mean I would look into it further before buying. Reading the reviews in eHam, etc, which I believe pointed to a good antenna not addressing your specific problem. However, having as much information as I have, I would have done what the first reviewer on eHam did. I would build my own and test it. >The Cobra Junior, a 72' long linear loaded dipole, looks interesting >in terms of a short antenna for low HF bands with reasonably low >losses. I have run some preliminary NEC models and analysed the feed >system loss with 25m of W551 ladder line, they look promising. I will >build a complete model over HF along the lines of the ones that >underly my article on the G5RV feed system at >http://www.vk1od.net/G5RV/index.htm . More when it is done in a day or >three. > I will be glad to look at that. I hope it helps the OP. >Owen Thanks, When looking at antennas, I first look at all the information available from the manufacturer, then I look for reviews such as at eham, and I might bring it up for question here and at similar forums. The antenna in question has no specifications or promises, per se, except for the claim that one can tune it to all the bands. This claim is reinforced by the reviews on eHam.com. As I said earlier, I wouldn't buy it, I would build it. I like doing that. :) If I were to purchase it and had an internal tuner in the rig, I would ask the maker or seller of the antenna if it is expected to work on my particular radio. He might inform me that the antenna might not work on some internal tuners and I would be better informed before I purchase. Of course, the OP apparently doesn't have this information, or didn't read it about his particular rig. Then again, there are very many external factors that could affect the antenna. I recently helped someone connect an 80 meter antenna to a TS-440 SAT which has an internal tuner. When we tested it in one position, it worked perfectly. However, when we added 6 feet of coax to move the radio and it suddenly tuned everywhere in the mars 4 mhz band except the area around which he meets in his net. We had to trim the antenna to make it match. Strange, but true. I didn't analyze the whys and wherefors, but we did get the man operating successfully, which was the purpose of our visit. Well, I have to get ready for that four letter word forbidden on local repeaters here. 73 for now. buck -- 73 for now Buck N4PGW Article: 225125 of rec.radio.amateur.antenna From: nospam@nouce.bellatlantic.net Subject: Re: Yet another 6m 3el Quad question Message-ID: <0iri82ddntkd67rnrhlfse4p7dtup9lroa@4ax.com> References: Date: Fri, 09 Jun 2006 12:51:10 GMT On Wed, 7 Jun 2006 12:22:22 -0500, "Ken Bessler" wrote: >My Quad is all built and I'm waiting or FedEx to deliver >my rotor. I built the quad out of wood, with a 1-1/4" dia >pine boom and 4' mast plus 1/4"x48" spruce dowels for >spreaders. I used insulated 16g stranded wire for the >elements. All the wood is either painted or treated with >sealer. > >Problem is I just broke a spreader moving the antenna and >I'm worried about how fragile the whole design is. Would >the performance change much if I used 1/4" aluminum rods >instead? Maybe I should just get some fiberglass resin and >paint the spreaders with several coats? How about wrapping >them in re-enforced boxers tape (the good stuff with fibers >in the tape)? > >Thanks for the help, guys.... The idea of metal will not work for spreaders. The 1/4" spreaders are way to light to survive. Last quad I did using dowels for spreaders I used 1/2" and even then it didn't take much abuse. I tried 3/8" fiberglass rods but they tended bend in the wind. Gave up on quads for 6m at that point and did a Yagi which had a lower wind profile. Allison Article: 225126 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Buyer Beware - Cobra Ultralight Date: Fri, 09 Jun 2006 09:05:40 -0400 Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Owen Duffy wrote: > On Thu, 08 Jun 2006 20:33:12 -0400, Mike Coslo > wrote: > > >> I'd buy a tuner that will handle open wire feed, lose the 4:1 balun, >> and get on the air. > > Mike, did you notice "Mystery's" comment re spending more money on a > "tuner extender": "Not the answer I wanted to hear". She/he may be > even less interested in the spend on the tuner you describe. Of course. But sometimes the unwanted answer is still the correct or best one..... > I agree with you that antenna looks worth a try / perseverance, but it > will probably need a wider range tuner than commonly fitted internal > to transceivers unless you experiment (what's that!) to find a > feedline length that the rig/runer accommodates on all bands, or > switch feedline lengths. Sounds like time for Cecil to join in. I know his system uses switchable lengths of twinlead, but perhaps he might have something to offer here in a one length feedline system. - 73 de Mike KB3EIA - Article: 225127 of rec.radio.amateur.antenna From: Eskay Subject: Re: 2 element gem quad References: Message-ID: <77mccbiof67$.1130uqrihfb7f$.dlg@40tude.net> Date: Fri, 09 Jun 2006 13:06:44 GMT On Fri, 09 Jun 2006 00:19:31 +0100, mike wrote: > Hi All > Would anyone using a 2 element gem quad like to talk to me > about putting the antenna together > > please reply direct > Thanks > 73 de Mike G4KHB Don't you have the instructions? Article: 225128 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Buyer Beware - Cobra Ultralight Date: Fri, 09 Jun 2006 09:10:44 -0400 Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <1149817448.339895.295850@u72g2000cwu.googlegroups.com> <128hme8sbfdeoe6@corp.supernews.com> Dave Platt wrote: >>>> same antenna I purchased. I bought the Cobra junior antenna and >>>> followed the directions for installation. The antenna is 50ft in the >>>> air in a flat top configuration. When I hooked it up to my radio, it >>>> would not tune on segments of certain bands, most noticeably 75/80. I >>> That all seems pretty reasonable though the explanation that the >>> "built in tuner would not accept more than a certain level of SWR" is >>> not a good way to express the limits of internal tuners, but it is an >>> explanation that would appeal to those with lesser knowledge. >> The problem is that antenna is advertised to work all bands. >> Unfortunately it doesn't do very well on many bands. >> >> The SWR is "off the scale" on many bands. > > The same would be true of almost any other doublet-style antenna, I > think. Such antennas are often usable on a large number of bands if > you have a wide-range transmatch/tuner, but I don't think I know of > any which are usable in this way with the limited-matching-range > "line flattener" ATUs built into modern solid-state transceivers. > > The Cobra Ultralight is only about 60% as long as a normal resonant > near-half-wave dipole for 75/80 meters. It's shortened by linear > loading. I imagine it has a narrower SWR bandwidth than a simple > dipole. Which right away spells trouble when trying to match the huge 85-75 meter bands. > The manufacturer states that a tuner _is_ required. The wording is > perhaps somewhat more optimistic about using a transceiver's built-in > ATU than is justified, though. I wouldn't plan to use an antenna of > this sort without a good external tuner with balanced-output > capability (whether intrinsic or via a good current balun). > > The original poster might want to consider making a multi-wire (or > "fan") dipole. With several sets of wires it'd surely be possible > to make one which would tune on 80, 75, 40, and 20 well enough to not > need an external tuner... although fitting it into under 80 feet of > linear space might prove to be a challenge. Or an off center fed dipole. If he can get that antenna up 50 feet, the ends can droop down. - 73 de Mike KB3EIA - Article: 225129 of rec.radio.amateur.antenna From: "Jerry" References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <1149821546.632074.199040@f6g2000cwb.googlegroups.com> Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: <%vfig.7446$gv2.424@bignews3.bellsouth.net> Date: Fri, 9 Jun 2006 10:23:55 -0400 "pbourget" wrote in message news:1149821546.632074.199040@f6g2000cwb.googlegroups.com... >I have the Ultralite Senior and am very happy with it. I have it at 30 > feet with the ends dropping down about 15 feet since my lot isn't big > enough. I bought it primarily as a local contact antenna since > everything else I have is a vertical of one type or another. It turns > out to work much better than I expected. I have worked the South > Pacific, Europe and Peter One on it with 100 watts. I use the full 100 > feet of ladder line it came with to a 4:1 balun through a remote > antenna switch and 50 feet of LMR400 coax. Sometimes it receives better > than my verticals and it almost always is quieter. In fact that is why > I used it for Peter One, I couldn't pick what calls they were coming > back to because of the noise on the vertical and half square. My TS-480 > internal tuner tunes it on every band, even 6 meters which there are no > claims for. > > Pete W6OP > > Jerry wrote: >> wrote in message >> news:1149770557.629987.141180@i40g2000cwc.googlegroups.com... >> > > Yes, the Ultralite Senior is quite effective! Mine is at 60 feet at the apex and the "Vee" droops down to about 20 or so. I get pretty nice signal reports both from local and afar. You can't always win 'em all, but when an antenna works *reasonably* well most anywhere you work, a fella can't ask for much more! And I am perfectly happy with mine. 73 Jerry K4KWH Article: 225130 of rec.radio.amateur.antenna From: "Jerry" References: Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Message-ID: Date: Fri, 9 Jun 2006 10:39:47 -0400 "Slow Code" wrote in message news:WpEhg.2725$lp.611@newsread3.news.pas.earthlink.net... > No more automatic renewals. Individuals must retest and pass all elements > required for their license class. > > > The passing score for written exams needs to be raised to 85%. > > > Code elements should be 13 wpm for General, and 20 wpm for Extra. > > > Make the no-code Tech license one year non-renewable. AH! HA! We can dress our daughters in poodle skirts and drive to the testing session in our brand-new 1961 Chevrolet Impala Sport Sedan! Time marches on, boys, and as we age into crotchety old men (Gosh, I hope I don't do the "crotchety" part!), we long for the 'good old days'---whatever THAT was. Some of us cling desperately to Hallicrafters receivers and Globe King transmitters we bought when our hair was dark and full, and loathe the new 'mini' transceivers (likely because we are befuddled by the menus), and we want Amateur Radio to stay exactly the same as it was *just* for us! We fuss at the newer automobiles and say "I wish they made 'em the way they used to". I DON'T! They are actually BETTER than Dad's '65 Galaxie, last longer and run better. (Try to tell that to the past-dwelling guys who cling frantically to their youth, and they'll lecture you on the virtues of a '56 Chevy AND the 51J2...not that the older stuff isn't "good", just part of the PAST! Which we, BTW, should remember as a basis for advancing into the future. I don't really like it that CW is going away, but it WILL go away so far as necessity goes same way we don't commute to work in our '56 Fairlane. So we ADAPT to change instead of vainly clinging to the way WE think it should stay forever and a day. When we are dead and gone, the world will be vastly different than we would've remembered it! 73 Jerry > > > sc > > > Article: 225131 of rec.radio.amateur.antenna From: "Steve N." Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Date: Fri, 9 Jun 2006 10:23:47 -0500 Message-ID: References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <1149724604.928282.248280@u72g2000cwu.googlegroups.com> <128ercucqikj3b0@corp.supernews.com> <1149773576.391521.292660@h76g2000cwa.googlegroups.com> <128gag4l6ir25e0@corp.supernews.com> > > Somebody wrote: > > No. This is an honest to god left handed crescent style wrench. Hold in > > left hand and close the jaws using the left thumb. > > I have a metric one :-) > > Yep ! Me too. I have a 150mm "Crescent" wrench! Works great on metric nuts & bolts. 73, Steve, K9DCI Article: 225132 of rec.radio.amateur.antenna From: "Steve N." Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Date: Fri, 9 Jun 2006 10:20:52 -0500 Message-ID: References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Ahhhh!! Those only work when it rains capacitors !. 73, Steve, K9DCI "John S." wrote in message news:1149714609.565540.160300@c74g2000cwc.googlegroups.com... > > New Ham wrote: > > Did I get ripped off? > > You might try a Stetson. > Article: 225133 of rec.radio.amateur.antenna From: "Steve N." Subject: Re: impedance Date: Fri, 9 Jun 2006 10:30:45 -0500 Message-ID: References: Look for "Parallel plate capacitor" formula. 73, Steve, K9DCI "kretko" wrote in message news:e68h17$gl3$2@nemesis.news.tpi.pl... > Hello ! > > Im looking for a formula impedance of conductor between two ground plane. > > _________ > * > h1 > * > p > * > h2 > * > _________ > > p -conductor > h1 = h2 > > Thank you for your help ! > > Goodlack ! ! ! Article: 225134 of rec.radio.amateur.antenna From: "WX" References: <9e847$4482def6$d06640f9$28274@FUSE.NET> <1149441418.531073.162560@j55g2000cwa.googlegroups.com> <1149606997.736862.209000@c74g2000cwc.googlegroups.com> <1149684175.500749.17370@f6g2000cwb.googlegroups.com> <1149701987.056423.87510@i40g2000cwc.googlegroups.com> <1149773589.092481.119850@i39g2000cwa.googlegroups.com> <1149783867.303127.313090@y43g2000cwc.googlegroups.com> <1149856546.597189.321690@y43g2000cwc.googlegroups.com> <1149870517.893244.250120@i40g2000cwc.googlegroups.com> Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Tue, 6 Jun 2006 06:22:47 +0200 Message-ID: <4489a67c$0$29724$4fafbaef@reader2.news.tin.it> http://home.planet.nl/~pa3ebt/IARU-R1/25_5.htm Article: 225135 of rec.radio.amateur.antenna From: Bruce in Alaska Subject: Re: RF grounding methods for sailboats: A Summary References: <1148994725_36063@sp6iad.superfeed.net> <6ggr72509n8k0ulii7a3j574e6ogiuhrbp@4ax.com> <1149107678_2377@sp6iad.superfeed.net> <447ec69c_1@news.iprimus.com.au> <128278grmhthsab@corp.supernews.com> <1288u8idqtf9b0a@corp.supernews.com> Message-ID: Date: Fri, 09 Jun 2006 17:44:33 GMT In article , Mike Coslo wrote: > Well, I could be wrong, but if one side of the capacitor is on the > inside of the hull, and the other side is the sea water, is not the > motion of the ship going to affect that? ships move up and down quite a > bit, and low draft ones can have a *lot* of that hull out of the water, > and then a few seconds later have water coming over the bow. We are not talking about 16 foot dingys here, we are talking about vessels mostly over 30 feet in length, and usually with over 3 or 4 feet of draft. Just how much coupling to the seawater you have is a function of area of the inside capacitive plate, and the distance between it and the seawater. If the dielectric distance is a few inches, and the inside plate is below the waterline, then coupling will not change apperciably, just because the water is sloshing around a bit on the hull. Even if a bit of the surface area of the inside plate did come above the waterline for a little while, say on a hard tack in a sail rig, the coupling still wouldn't be appreciably reduced by loosing 5% of the surface area. These are not really valid problems that one sees, when operating MF/HF Marine Radios that have a decent, Low Impedance RF Ground System installed in the first place. doing it right the first time solves a lot of ills down the road, and skimping on the RF Ground, is a presciption for disaster. Bruce in alaska long time Marine RadioMan....... -- add a <2> before @ Article: 225136 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Sinusoidal Antenna Currents References: Message-ID: Date: Fri, 09 Jun 2006 21:26:39 GMT Dave wrote: > i believe in this description he is refering to the current distribution of > the standing wave. that is, the classical sine curve that shows a maximum > at the feedpoint of the 1/2 wave dipole and zeros at the ends. in this case > the shape of the curve is a function of the sin or cos of the distance from > the feedpoint divided by the leg length times pi/2 or 90 degrees, which ever > you prefer. Exactly, and that is the number of degrees by which the forward traveling wave lags the source wave and therefore is the phase angle of the forward traveling wave reference to the source wave. > however, that is not the phase of the forward traveling wave, ... Of course it is, referenced to a source phase angle of zero. Assuming the source phase reference is zero degrees, the phase of the forward traveling wave is related to the distance from the source (modified by the velocity factor). That's just simple physics. Given the source current is 1.0 amps at zero degrees, the standing wave current 1/2 way to the end of the antenna element will be 0.707 amps at zero degrees. Arc-cos(0.707) = -45 degrees. That's the phase angle of the forward current at that point since it lags the source current. Hint: There are very close to 90 degrees of antenna between the source and the end of a 1/2WL dipole since it is 1/4 wavelength. Remember 360/4 = 90 degrees. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225137 of rec.radio.amateur.antenna From: "Jimmie D" References: <8gBhg.18641$VE1.11065@newssvr14.news.prodigy.com> Subject: Re: Quad feedpoint Message-ID: Date: Fri, 9 Jun 2006 17:51:55 -0400 "Ian White GM3SEK" wrote in message news:syrcA5Pj9vhEFAFo@ifwtech.co.uk... > Cecil Moore wrote: >>Ken Bessler wrote: >>> I just built a 3el 6m quad. Should I put a choke or balun >>> at the feedpoint? What type? >> >>A few turns of coax will do the trick for 6m. >>How about this solution from an earlier posting? >> >>| >>| >>| Driven >>| Element >>| >>+====================================coax braid >> >>+------------------------------------coax center conductor >>| >>| ==============================+===coax braid >>| spacing | >>+--------------------------------+ >>| 1/4WL wire (~4.7') >>| >> > The choke balun made from a small coil of coax would be easier to make. At > my previous QTH, four turns of about 6in diameter made a big reduction in > the levels of noise and birdies on 6m (even though those coil dimensions > weren't optimized in any way). > > This kind of feedline choke is simple, cheap and low-loss, so by all means > go ahead and use one. With a 3-element quad, you should be able to > position the coil at the feedpoint while supporting its weight from the > mast. > > > > > > -- > 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) > http://www.ifwtech.co.uk/g3sek Using a choke made a big difference in TVI for me. Article: 225138 of rec.radio.amateur.antenna From: "Jimmie D" References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Message-ID: Date: Fri, 9 Jun 2006 18:10:59 -0400 "Dave Oldridge" wrote in message news:Xns97DBA9FEC980Cdoldridgsprintca@64.59.135.159... > Jim - NN7K wrote in news:blJhg.19147 > $VE1.18282@newssvr14.news.prodigy.com: > >> Reminds me of the time (many years ago), when the >> new kid on the gang was ordered to "Wash the >> Dishes" (microwave ), on a 150 foot tower ! Kid >> decided it was time to quit! Had to >> tell him it was a JOKE, or get the WHOLE Gang >> in hot water !!! Jim NN7K > > Yeah. When I was in the RCAF many years ago, a common thing was to ask a > newbie to go to the tool crib for a bucket of propwash. > > > -- > Dave Oldridge+ > ICQ 1800667 When I reached my first duty assignment in the USAF I was sent on a fools errand to get 1000 yards of flight line. When I got to the place I was suppose to pick it up I told the guys there that I knew what flightline was but I had an idea for a joke on the guy that sent me down there.They were very happy to help. We went out back of the base and loaded up a truck with rubble from flightline construction then took it back and put it the POV pickup of they guy who had sent me out. When I went back to the shop I told him I had the flightline but didnt think I had the thousand yards he had requested. This got him and everyone else in the shop curious and they all wanted to see what I had brought back. Thats when I told him to go look in the back of his pickup. Article: 225139 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: <9luj82h4k68g3r71qm0c4qd3ijie9pk4ei@4ax.com> References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Fri, 09 Jun 2006 22:58:27 GMT On Fri, 09 Jun 2006 15:33:59 GMT, Cecil Moore wrote: >One thing interesting about the Cobra-Jr is that if it is >made 62 feet long instead of 73 feet long, it becomes >resonant around 3.85 MHz with a feedpoint impedance of >about 16 ohms. That's an SWR of only about 3:1 on coax. >or ~1.3:1 using a 1:4 balun. That's a half size antenna >for 75m that is only about 1.5 dB down from a full size >1/2WL dipole. Where are you observing resonance? I created a model with ~73' length that does resonate (low Z) at the dipole centre around 3.6MHz. Other factors affect resonance a little, but you may want to check your model to see it is laid out properly and connected up properly. Owen -- Article: 225140 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Noise level between two ant types Message-ID: Date: Fri, 9 Jun 2006 21:27:25 -0500 Take 2 antennas on 6m - one is an inverted V and the other a 3el quad. Both are mounted at near the same height and fed with about the same length of coax. Is it normal for the quad to be quieter? Signals are louder on the quad - it's just the background noise is higher on the V. Just curious..... -- 73's de Ken KG0WX - Kadiddlehopper #11808, Flying Pigs #-1055, Grid EM17io, FT-857D, AL-84, Elecraft XG2, 4SQRP Tenna Dipper, Heath GD-1B Article: 225141 of rec.radio.amateur.antenna From: Buck Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Sat, 10 Jun 2006 00:42:57 -0400 On Fri, 09 Jun 2006 00:59:53 GMT, Owen Duffy wrote: >Mike, did you notice "Mystery's" comment re spending more money on a >"tuner extender": "Not the answer I wanted to hear". She/he may be >even less interested in the spend on the tuner you describe. > >I agree with you that antenna looks worth a try / perseverance, but it >will probably need a wider range tuner than commonly fitted internal >to transceivers unless you experiment (what's that!) to find a >feedline length that the rig/runer accommodates on all bands, or >switch feedline lengths. > >Owen How is the "tuner extender" made? is it simple enough to duplicate with a home-brew? -- 73 for now Buck N4PGW Article: 225142 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Message-ID: Date: Fri, 9 Jun 2006 22:08:37 -0700 "Jerry" wrote in message news:SKfig.7450$gv2.4890@bignews3.bellsouth.net... < snip > > I don't really like it that CW is going away, but it WILL go away so far as > necessity goes same way we don't commute to work in our '56 Fairlane. So we > ADAPT to change instead of vainly clinging to the way WE think it should > stay forever and a day. When we are dead and gone, the world will be vastly > different than we would've remembered it! It isn't going away any more than tubes are going away or crystal-controlled oscillators are going away. Those of us who wish to use them are free to do so (and this freedom will probably continue for a long time). Railroad fans admire steam locomotives, car buffs fawn over a Model T and old men love their old wives. But in each case, the object of their affection is, like Morse Code, past its peak of popularity and practicality. Yes, learn Morse, use Morse, even love Morse -- but for crying out loud, stop pretending it's the be-all-end-all of ham radio -- because it isn't. Yes, yes, yes -- I know Morse Code will get through when other modes fail. I've heard it a hundred times, so it must be true. However, this doleful situation almost never presents itself. If this were a practical view of the world, then we should all buy Army tanks, the better to navigate the rubble of a natural disaster when all other means of transportation are unavailable. (Not a perfect metaphor; work with me, OK?) Although I have no objection to YOU using Morse Code, I personally resent it because I can't learn it. I've wasted countless hours trying and it just doesn't happen for me. Too bad, so sad. But there are rays of sunshine. The FCC may just lift the requirement off my shoulders before another year passes and in the meantime, maybe I'll rack up more club FD points on UHF/VHF voice than the HF guys on all modes combined. I did it in both 2004 and 2005. "Sal" (KD6VKW) Article: 225143 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> Date: Sat, 10 Jun 2006 05:25:54 GMT On Fri, 09 Jun 2006 05:13:04 GMT, Owen Duffy wrote: >The Cobra Junior, a 72' long linear loaded dipole, looks interesting >in terms of a short antenna for low HF bands with reasonably low >losses. I have run some preliminary NEC models and analysed the feed >system loss with 25m of W551 ladder line, they look promising. Well, the antenna system looks promising on some bands, but not others. Draft article is at http://www.vk1od.net/cobra , constructive comments appreciated. The article includes a link to a graph of the modelled system losses for the Cobra Senior, but it looks pretty uninteresting with ~9dB of system loss at 160m... there is no shortage of poor performing antennas on 160m. Owen -- Article: 225144 of rec.radio.amateur.antenna From: Alan Peake Subject: Re: impedance Date: Sat, 10 Jun 2006 17:38:25 +1000 Message-ID: <448A76F1.6070302@killspam.internode.on.net> References: kretko wrote: > Hello ! > > Im looking for a formula impedance of conductor between two ground plane. > > _________ > * > h1 > * > p > * > h2 > * > _________ > > p -conductor > h1 = h2 > > Thank you for your help ! > > Goodlack ! ! ! OK, let h=2*h1 and d= wire diameter Then, for p/h < 0,75 Zo = (138/sqrt(e))*log10(4h/(pi*d)) where pi = 3.14159.... and e = 2.7183... Alan Article: 225145 of rec.radio.amateur.antenna From: "Boborato" Subject: FM without 'pink noise' Date: Sat, 10 Jun 2006 05:55:25 -0400 Message-ID: Hi group. I wanna know how can I get the FM signal without that nasty 'pink' noise. I'm not using any kind of external antenna. Greetings!! Article: 225146 of rec.radio.amateur.antenna From: "Richard Fry" References: <1149883021.281768.106120@y43g2000cwc.googlegroups.com> Subject: Re: coverage analysis using TIREM Date: Sat, 10 Jun 2006 07:02:18 -0500 Message-ID: <448ab3fd_2@newsfeed.slurp.net> "MRW" wrote > ... Why did my signal level drop at 100 ft? _____________ The number that TIREM calculates will depend among other things on the vector sum of the direct and ground-reflected or diffracted rays for the model conditions -- which are a function of ERP, antenna height, path length, and the terrain profile along that radial. Probably the combination of these at the 100 ft elevation of the transmit antenna was responsible for the result you saw. If you get a chance, check several other radials to see what happens. RF Article: 225147 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Dumb question #433,444,007 Message-ID: <%Gyig.40099$4H.35436@dukeread03> Date: Sat, 10 Jun 2006 07:12:42 -0500 If I prune the driven element on my 6m 3el quad for best swr, do I have to do anything to the reflector or director? -- 73's de Ken KG0WX - Kadiddlehopper #11808, Flying Pigs #-1055, Grid EM17io, FT-857D, AL-84, Elecraft XG2, 4SQRP Tenna Dipper, Heath GD-1B Article: 225148 of rec.radio.amateur.antenna From: "Ken Bessler" References: Subject: Re: FM without 'pink noise' Message-ID: Date: Sat, 10 Jun 2006 07:25:12 -0500 "Dave" wrote in message news:hcadnTpysL_RJBfZnZ2dnUVZ_qWdnZ2d@comcast.com... > Pray tell, in 50+ years of ham radio I have never heard 'pink noise'. > > What is it?? > > Boborato wrote: > > Hi group. > > > > I wanna know how can I get the FM signal without that nasty 'pink' noise. > > > > I'm not using any kind of external antenna. > > > > Greetings!! > > > > > I just used NCH tone generator to make pink noise - sounds like what you hear on a AM when you open the squelch. I can email you a sample if you'd like. :-) Ken Article: 225149 of rec.radio.amateur.antenna From: "Richard Fry" References: Subject: Re: FM without 'pink noise' Date: Sat, 10 Jun 2006 08:06:10 -0500 Message-ID: <448ac2f5_5@newsfeed.slurp.net> "Boborato" > > I wanna know how can I get the FM signal without that > nasty 'pink' noise. I'm not using any kind of external antenna. ________________ An FM receiver needs a certain minimum level of r-f voltage at its antenna input terminals to meet its noise performance specification. Stereo mode requires more r-f than monaural, for the same S/N at the receiver output. No doubt if you use an antenna capable of giving your receiver the r-f input signal it needs, your noise level will drop to inaudibility (at least with normal programming). RF Article: 225150 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> Message-ID: Date: Sat, 10 Jun 2006 14:07:48 GMT Not to mention that noise is normally a phenonmen of the Vertical Plane (which , depending on how steep your inverted "vee" is, will contain some vertical component, while the yagi/quad is Horizontal to the plane. This has been a factor on vhf for years, as noise levels tend to peak at 6 meters (50 MHz). The MAIN reason that F.M. is Vertical polarized is that for mobiles, it is easy to construct an omni-directional antenna. Most vhf manuals detail this effect! Jim NN7K w8ji@akorn.net wrote: > Ken Bessler wrote: > >>Take 2 antennas on 6m - one is an inverted V and the >>other a 3el quad. Both are mounted at near the same >>height and fed with about the same length of coax. >> >>Is it normal for the quad to be quieter? > > > Noise almost always arrives from multiple directions and from different > directions than the desired signal. > > It is normal for ANY antenna to be quieter when it is more directional. > As a matter of fact, it is expected that S/N ratio is a direct function > of directivity of the antenna as long as the noise and signal are not > coming from the same direction. > > To answer your question, it would be very abnormal if your quad (or > Yagi or any other directional antenna) was noisier than a broad pattern > antenna like your Inverted Vee dipole. > > 73 Tom > Article: 225151 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Dumb question #433,444,007 References: <%Gyig.40099$4H.35436@dukeread03> Message-ID: Date: Sat, 10 Jun 2006 14:22:31 GMT Ken Bessler wrote: > If I prune the driven element on my 6m 3el quad for best > swr, do I have to do anything to the reflector or director? For beams, the desired radiation pattern is usually more important than minimum SWR. Using EZNEC, I've seen a 4:1 SWR yield the desired pattern where at the minimum 1.5:1 SWR point the F:B ratio was terrible. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225152 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> Message-ID: Date: Sat, 10 Jun 2006 14:25:50 GMT Jim - NN7K wrote: > Not to mention that noise is normally a phenonmen of the Vertical Plane > (which , depending on how steep your inverted "vee" is, will contain some > vertical component, while the yagi/quad is Horizontal to the plane. Quads are a lot less noisy than Yagis when the wind is blowing in the Arizona desert. Quads have a DC short across the feedpoint that reduces noise from static buildup. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225153 of rec.radio.amateur.antenna From: "W3JDR" References: Subject: Re: FM without 'pink noise' Message-ID: Date: Sat, 10 Jun 2006 15:52:24 GMT Dave, If you've never heard of 'pink' noise, then you're probably not a student of noise. In noise parlance, 'white' noise is the term that is usually used for non-bandlimited noise (ie, 'broadband noise'). "Pink' noise, on the other hand, is a term used to refer to bandlimited noise. In practice, anything that comes out of the audio channel of a communications receiver is really 'pink' noise, as the bandwidth is limited to a few KHz. On the other hand, the noise that is incident at the antenna or generated in the front-end is much broader in bandwidth and is more deserving of the term 'white' noise. Joe W3JDR "Dave" wrote in message news:hcadnTpysL_RJBfZnZ2dnUVZ_qWdnZ2d@comcast.com... > Pray tell, in 50+ years of ham radio I have never heard 'pink noise'. > > What is it?? > > Boborato wrote: >> Hi group. >> >> I wanna know how can I get the FM signal without that nasty 'pink' noise. >> >> I'm not using any kind of external antenna. >> >> Greetings!! > Article: 225154 of rec.radio.amateur.antenna From: "Ken Bessler" References: <%Gyig.40099$4H.35436@dukeread03> Subject: Re: Dumb question #433,444,007 Message-ID: Date: Sat, 10 Jun 2006 12:12:13 -0500 "Cecil Moore" wrote in message news:HAAig.94653$H71.12190@newssvr13.news.prodigy.com... > Ken Bessler wrote: > > If I prune the driven element on my 6m 3el quad for best > > swr, do I have to do anything to the reflector or director? > > For beams, the desired radiation pattern is usually > more important than minimum SWR. Using EZNEC, I've > seen a 4:1 SWR yield the desired pattern where > at the minimum 1.5:1 SWR point the F:B ratio was > terrible. > -- > 73, Cecil http://www.qsl.net/w5dxp I did model this antenna with EZNEC but I forgot to take into account the fact that the wire used is insulated. I think that screwed up the resulting antenna. Maybe? Would an insulating jacket reduce the VF of the wire? I've accounted for everything else, wire gauge/loss, ant height, type of ground, etc. Ken KG0WX Article: 225155 of rec.radio.amateur.antenna Message-ID: <448B2227.2090601@fuse.net> Date: Sat, 10 Jun 2006 15:48:55 -0400 From: jawod Subject: Re: Have any of you mailed this to your ARRL Division directors and References: Sal M. Onella wrote: > "Jerry" wrote in message > news:SKfig.7450$gv2.4890@bignews3.bellsouth.net... > > < snip > > >>I don't really like it that CW is going away, but it WILL go away so far > > as > >>necessity goes same way we don't commute to work in our '56 Fairlane. So > > we > >>ADAPT to change instead of vainly clinging to the way WE think it should >>stay forever and a day. When we are dead and gone, the world will be > > vastly > >>different than we would've remembered it! > > > It isn't going away any more than tubes are going away or crystal-controlled > oscillators are going away. Those of us who wish to use them are free to do > so (and this freedom will probably continue for a long time). > > Railroad fans admire steam locomotives, car buffs fawn over a Model T and > old men love their old wives. But in each case, the object of their > affection is, like Morse Code, past its peak of popularity and practicality. > Yes, learn Morse, use Morse, even love Morse -- but for crying out loud, > stop pretending it's the be-all-end-all of ham radio -- because it isn't. > > Yes, yes, yes -- I know Morse Code will get through when other modes fail. > I've heard it a hundred times, so it must be true. However, this doleful > situation almost never presents itself. If this were a practical view of > the world, then we should all buy Army tanks, the better to navigate the > rubble of a natural disaster when all other means of transportation are > unavailable. (Not a perfect metaphor; work with me, OK?) > > Although I have no objection to YOU using Morse Code, I personally resent it > because I can't learn it. I've wasted countless hours trying and it just > doesn't happen for me. Too bad, so sad. But there are rays of sunshine. > The FCC may just lift the requirement off my shoulders before another year > passes and in the meantime, maybe I'll rack up more club FD points on > UHF/VHF voice than the HF guys on all modes combined. I did it in both 2004 > and 2005. > > "Sal" > (KD6VKW) > > too bad, so sad, indeed You know, as long as there are effective band plans allowing for CW, data, voice, etc., I really don't care what the FCC does. I learned Morse code as a teenager so I really can't relate to the impossibility of the task. Don't know how THIS old dog would do with a new trick. All I can say is CW is very enjoyable to me and deserves a prominent place within the bands. Article: 225156 of rec.radio.amateur.antenna Message-ID: <448B2E1B.37B37F6D@towerclimberguy.com> From: billy Subject: Re: 3 Killed in Fall From Iowa TV Tower References: Date: Sat, 10 Jun 2006 20:39:56 GMT hi this is indeed tragic accident and could have been prevented, tower workers are one of the top hazardous occupations with high rate of death. be care full up there Article: 225157 of rec.radio.amateur.antenna From: "Ken Bessler" References: <%Gyig.40099$4H.35436@dukeread03> Subject: Re: Dumb question #433,444,007 - Answer from ARRL Ant Book? Message-ID: Date: Sat, 10 Jun 2006 15:51:43 -0500 "Ken Bessler" wrote in message news:O3Dig.40117$4H.36191@dukeread03... > > "Cecil Moore" wrote in message > news:HAAig.94653$H71.12190@newssvr13.news.prodigy.com... > > Ken Bessler wrote: > > > If I prune the driven element on my 6m 3el quad for best > > > swr, do I have to do anything to the reflector or director? > > > > For beams, the desired radiation pattern is usually > > more important than minimum SWR. Using EZNEC, I've > > seen a 4:1 SWR yield the desired pattern where > > at the minimum 1.5:1 SWR point the F:B ratio was > > terrible. > > -- > > 73, Cecil http://www.qsl.net/w5dxp > > I did model this antenna with EZNEC but I forgot to take > into account the fact that the wire used is insulated. I think > that screwed up the resulting antenna. Maybe? Would an > insulating jacket reduce the VF of the wire? I've accounted > for everything else, wire gauge/loss, ant height, type of > ground, etc. > > Ken > KG0WX OK now I'm really starting to think I should prune my reflector and director - here's a quote from the ARRL Antenna Book 2003, page 12-4: "In practice, it has been found that the length around the loop should be approximately 3.5% greater than the self-resonant length if the element is a reflector, and about 3.0% shorter than the self-resonant length if the parasitic element is a director." I built my 6m quad with a 240.64" driven element which I had to trim 6" to get the SWR where I wanted it (low end of 50mhz). My reflector is 246.64" and my director is 233.41". Help? Do I trim or not? I have done some tests with the ant up and I'm noticing my F/B ratio is not as good as the EZNEC model predicted (30.62 db predicted, I'm seeing maybe 2-3db) Ken KG0WX Always learning...... Article: 225158 of rec.radio.amateur.antenna From: "Ken Bessler" References: <%Gyig.40099$4H.35436@dukeread03> <1149976234.598362.144030@g10g2000cwb.googlegroups.com> Subject: Re: Dumb question #433,444,007 - Answer from ARRL Ant Book? Message-ID: Date: Sat, 10 Jun 2006 16:55:54 -0500 wrote in message news:1149976234.598362.144030@g10g2000cwb.googlegroups.com... > > Ken Bessler wrote: > > Help? Do I trim or not? I have done some tests with the ant > > up and I'm noticing my F/B ratio is not as good as the EZNEC > > model predicted (30.62 db predicted, I'm seeing maybe 2-3db) > > > The Handbook means the self-resonant frequency with no other elements > around. They do NOT mean compared to the size of the driven element. > > A driven element can move higher or lower in frequency as you add other > elements, depending on the tuning of the other elements. > > I usually do all my F/B tuning first, and then SWR last. By the way, I > HOPE you have a balun at the feedpoint. Without a balun at the > feedpoint, the F/B can be seriously diminished. > > 73 Tom > I have about 8 turns of coax at the feedpoint. Is that good enough or do I need a 1:1 balun also? Thanks for the help! Ken KG0WX Article: 225159 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Dumb question #433,444,007 References: <%Gyig.40099$4H.35436@dukeread03> Message-ID: Date: Sat, 10 Jun 2006 23:50:02 GMT Ken Bessler wrote: > I did model this antenna with EZNEC but I forgot to take > into account the fact that the wire used is insulated. I think > that screwed up the resulting antenna. Maybe? Would an > insulating jacket reduce the VF of the wire? Yes, most of us have been bitten by that bug in our thinking. Exactly the same thing happened to me with "My Favorite Loop Antenna" on my web page. If I remember correctly, the insulated effect is around 3% on VF. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225160 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> Message-ID: Date: Sat, 10 Jun 2006 23:54:20 GMT Dave wrote: > Methinks your leg was being pulled. > > The SWR with the apostrophe s is a grammatical error. The apostrophe s > indicates that the SWR is possessive, that the SWR owns something; or, > that the SWR is doing something. The apostrophe s is not plural!! On the contrary, the plural of the letter A is A's. The plural of the number 3 is 3's. It's not too much of a stretch to assume that the plural of SWR is SWR's. From Webster's: "apostrophe - a make used to indicate ... the plural of letters or figures." -- 73, Cecil http://www.qsl.net/w5dxp Article: 225161 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> Message-ID: <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> Date: Sun, 11 Jun 2006 00:08:37 GMT w8ji@akorn.net wrote: > As a matter of fact if you research the quad, it was initially used to > eliminate corona at radio station HCJB. Yep, designed by my distant cousin, BTW. > Try this test, wire a small 2.5 MHh RF choke across your antenna and > check the before and after noise levels. They will not change. Obviously a false statement based on limited knowledge and experience. Any ham living around Phoenix will be glad to enlighten you. That's exactly how I eliminated the noise and arcing on my first bare-wire G5RV installed in Arizona. I didn't measure the change in noise level but it went from arcing at the coax connector to not arcing at the coax connector which was acceptable to me. If the driven element on a Yagi is an uninsulated dipole, it is susceptible to wind driven noise on the driven element just like my G5RV was. Just because you have never experienced that type of noise in Georgia doesn't mean it doesn't exist in Arizona. I dare say you haven't experienced a lot of things that exist in reality. Mary G. comes to mind. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 225162 of rec.radio.amateur.antenna From: "Ken Bessler" References: <%Gyig.40099$4H.35436@dukeread03> Subject: Re: Dumb question #433,444,007 Message-ID: Date: Sat, 10 Jun 2006 19:58:00 -0500 "Cecil Moore" wrote in message news:KUIig.94792$H71.82841@newssvr13.news.prodigy.com... > Ken Bessler wrote: > > I did model this antenna with EZNEC but I forgot to take > > into account the fact that the wire used is insulated. I think > > that screwed up the resulting antenna. Maybe? Would an > > insulating jacket reduce the VF of the wire? > > Yes, most of us have been bitten by that bug in our > thinking. Exactly the same thing happened to me with > "My Favorite Loop Antenna" on my web page. If I remember > correctly, the insulated effect is around 3% on VF. > -- > 73, Cecil http://www.qsl.net/w5dxp Thanks for the info, Cecil - I just got back in the shack from trimming all 3 elements. The SWR is now pretty close to what EZNEC predicted. I can't tell if I've got any pattern on SSB because 6 is wide open and full of contesters. There is a beacon 80 miles away that I'm hearing and I'll try to see what kind of pattern I have receiving that. Ken KG0WX Article: 225163 of rec.radio.amateur.antenna Date: Sat, 10 Jun 2006 21:21:11 -0500 From: Tom Ring Subject: Re: FM without 'pink noise' References: Message-ID: <448b7e17$0$6142$39cecf19@news.twtelecom.net> W3JDR wrote: > Dave, > > If you've never heard of 'pink' noise, then you're probably not a student of > noise. > > In noise parlance, 'white' noise is the term that is usually used for > non-bandlimited noise (ie, 'broadband noise'). "Pink' noise, on the other > hand, is a term used to refer to bandlimited noise. In practice, anything > that comes out of the audio channel of a communications receiver is really > 'pink' noise, as the bandwidth is limited to a few KHz. On the other hand, > the noise that is incident at the antenna or generated in the front-end is > much broader in bandwidth and is more deserving of the term 'white' noise. > > Joe > W3JDR > White noise is constant energy/Hz, pink is constant energy/octave. tom K0TAR Article: 225164 of rec.radio.amateur.antenna Date: Sat, 10 Jun 2006 22:06:19 -0500 From: Tom Ring Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> Message-ID: <448b88ac$0$76686$39cecf19@news.twtelecom.net> w8ji@akorn.net wrote: > > How many Yagi's have floating driven elements without ground paths? > None on VHF/UHF/SHF that I build and anyone I know builds. Maybe on HF it's different. I don't know why it should be, though. Although normally all the other elements float on anything but 6 meters. tom K0TAR Article: 225165 of rec.radio.amateur.antenna From: "Richard Crowley" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Date: Sat, 10 Jun 2006 21:11:04 -0700 Message-ID: <128n7597b11m190@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> "Cecil Moore" wrote ... > Dave wrote: >> Methinks your leg was being pulled. >> >> The SWR with the apostrophe s is a grammatical error. The apostrophe >> s indicates that the SWR is possessive, that the SWR owns something; >> or, that the SWR is doing something. The apostrophe s is not plural!! > > On the contrary, the plural of the letter A is A's. The plural > of the number 3 is 3's. It's not too much of a stretch to assume > that the plural of SWR is SWR's. > > From Webster's: "apostrophe - a make used to indicate ... the > plural of letters or figures." To take the argument well into absurdity (as if it needed any help), we can discuss whether your Webster's is descriptive or prescriptive. Article: 225166 of rec.radio.amateur.antenna From: "gravity" References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <2d0u3.bcp.17.1@news.alt.net> Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Date: Sun, 11 Jun 2006 01:05:40 -0500 Message-ID: <448bb2b6$0$16012$892e7fe2@authen.yellow.readfreenews.net> "Not Lloyd" wrote in message news:2d0u3.bcp.17.1@news.alt.net... > Well, Webster shows more than one error, at least insofar as formal English > goes. What Webster depicts is the "dumbing down" of what our kids are being > taught today. > Do what you wish, but those who are better educated will continue to use the > apostrophe to denote the possessive rather than the plural. > > more importantly, you didn't post with proper bracketed attributions (Cecil's comments in particular). so go somewhere else with your grammar Nazi crap, or i'll start with my proper netiquette rantings. Gravity Article: 225167 of rec.radio.amateur.antenna From: Alan Peake Subject: Re: impedance Date: Sun, 11 Jun 2006 17:08:55 +1000 Message-ID: <448BC187.2030906@killspam.internode.on.net> References: <448A76F1.6070302@killspam.internode.on.net> <1149954456.683350.38020@m38g2000cwc.googlegroups.com> K7ITM wrote: > Ahem. In your formula, e is the relative dielectric constant of the > dielectric between the planes and surrounding the wire, NOT the base of > natural logarithms. And I assume that "p/h < 0,75" should be d/h < > 0,75. Then it's equivalent to what I posted earlier. > > Cheers, > Tom Ooops! - I just knew I'd get it wrong somewhere:} Yes, I meant to say d/h as that was the formula in "Reference Data for Radio Engineers". Didn't see your post. Must be the weather here - snowing! Alan Article: 225168 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> Message-ID: Date: Sun, 11 Jun 2006 14:16:55 GMT w8ji@akorn.net wrote: >>> Try this test, wire a small 2.5 MHh RF choke across your antenna and >>> check the before and after noise levels. They will not change. > Cecil Moore wrote: >> Obviously a false statement based on limited knowledge and >> experience. > > When did you do that test? Around 1990 to cure the arcing at the coax connector during clear-sky high-wind conditions in the Arizona desert. When I got rid of the coax and used ladder-line all the way to the tuner, I discovered that the 4:1 balun in the MFJ tuner accomplished the same anti-arcing function so hams using ordinary 4:1 voltage baluns are equalizing that charge before it can arc. > When did you compare other antennas, like noise on plummer's delight > antennas? The noise was the arcing of the coax connector at the input to my IC-745 which woke me up at night and scorched my rug after I disconnected it and laid it on the floor. Seems obvious that going from arcing to not arcing changes the noise level. I was afraid to turn the transceiver on during the arcing process. If I had known I was ever going to have this conversation with a doubting Thomas, I would have hung an o'scope on it. The condition is well known to most desert hams but I had just moved there from Silicon Valley. I never experienced the condition in Silicon Valley or East Texas. Installing the RF choke across the antenna feedpoint cured the problem. I'm not talking about plumber's delight antennas here. I am discussing Yagis and other antennas whose driven elements are center-fed dipoles where there is no DC path between the driven elements. > How many Yagi's have floating driven elements without ground paths? It only takes one red car to disprove the assertion that all cars are white. All the Yagis that I have built used isolated dipole elements and it only takes one to demonstrate the clear- sky high-wind noise problems in the Arizona desert. Every Arizona desert ham running bare isolated HF elements with no DC path to ground will encounter the problem sooner or later. The problem has been discussed here on this newsgroup in the past, possibly while you weren't reading it. As I remember, one ham solved the problem with a 10K 3 watt carbon resistor across the feedpoint. It seems apparent to me that the problem occurs in very low humidity conditions. That would include dust and dry-air snow. And the dust doesn't have to be visible to the naked eye. I've seen it happen with clear-sky and seemingly clear-air conditions with high winds and low humidity. I suspect dust/pollen particles too small to see still carry a dry-air charge. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225169 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> Message-ID: <3OVig.44070$4L1.20408@newssvr11.news.prodigy.com> Date: Sun, 11 Jun 2006 14:30:23 GMT Richard Crowley wrote: > "Cecil Moore" wrote ... >> From Webster's: "apostrophe - a make used to indicate ... the >> plural of letters or figures." > > To take the argument well into absurdity (as if it > needed any help), we can discuss whether your > Webster's is descriptive or prescriptive. That definition agrees with what I learned in English class 50+ years ago. The plural of a number uses an apostrophe. So 73's would indeed be the plural of 73 as in "many best regards". It's no stretch to assume that the plural of SWR would be SWR's. Incidentally, I have an obvious typo in the definition that the spell-checker didn't catch. Should have been: "apostrophe - a mark used to indicate ... the plural of letters or figures." I have a "Webster's New Universal Unabridged Dictionary" which contains a "Basic Manual of Style" in the back. Here's what it says for "Apostrophe: ... 3. To form the plurals of letters or figures add an apostrophe and an s." That's seems to be prescriptive. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225170 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <2d0u3.bcp.17.1@news.alt.net> Message-ID: Date: Sun, 11 Jun 2006 14:49:51 GMT Not Lloyd wrote: > Do what you wish, but those who are better educated will continue to use the > apostrophe to denote the possessive rather than the plural. Would a "Basic Manual of Style" change your mind? I have a "Webster's New Universal Unabridged Dictionary" which contains a "Basic Manual of Style" in the back. Here's what it says for "Apostrophe: 1. ... 2. ... 3. To form the plurals of letters or figures add an apostrophe and an s. ..." It does say that a few people object to number 3. As in many other areas of the English language, the context of the use of the apostrophe determines its function: 1. to replace missing letters, 2. possessive, 3. plurals of letters or numbers. P.S. The better educated posters avoid violating the attribution rules for newsgroups. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225171 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> Message-ID: <38Wig.44074$4L1.17246@newssvr11.news.prodigy.com> Date: Sun, 11 Jun 2006 14:53:51 GMT Ian White GM3SEK wrote: > This makes the choices quite complex, and makes generalization > impossible. Quote an example, and someone else will quote you a > counter-example. Seems the assertion should be that precipitation noise can exist on some antennas but not on others. > Just one other thing: PLEASE let's not talk about elements being > "grounded", way up there at the top of a tower. How about "DC grounded"? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225172 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <1150030449.970907.232220@c74g2000cwc.googlegroups.com> Message-ID: <5xWig.146019$F_3.21643@newssvr29.news.prodigy.net> Date: Sun, 11 Jun 2006 15:20:34 GMT w8ji@akorn.net wrote: > People actually seem to think the little particles voving through the > air charge the antenna to a different potential than the air around the > antenna, and that a "dc" path to earth or "dc" path around an element > somehow magically stops RF noise. Please don't accuse people of believing in magic until you understand the physics involved. There's no magic involved. Dry-air dust and snow particles certainly can transfer a charge to an uninsulated wire in the air. It is simple physics to realize that when a highly charged particle touches a conductor, the charges between the two objects will be equalized. It would be magic if the particle and the wire did NOT equalize their charges by transferring excess differential charge when they come into contact. Given a dipole where one element has a DC path to ground and the other element is floating with respect to ground, it is reasonable to expect the charge between the two elements to be different and they often are. The difference in charge will build up to the point where the smallest gap between the two conductors arcs. In my configuration in the Arizona desert, that gap existed at the coax connector at the transceiver and it did indeed arc badly. It woke me up and scorched my rug after I disconnected it from my transceiver. The arc was bright enough to light up the room and certainly caused RF noise. The wind was blowing around 30 mph and there wasn't a cloud in the sky. Given an extreme relative charge between the element with a DC path to ground and the element without a DC path to ground, anything that will bleed off that charge will cure the problem. An RF choke works. A 4:1 voltage balun works. A resistor works. Perhaps we can convince a desert ham to hang an o'scope on a clear-sky, dry-air system on a windy day and report back here with some results. Many other hams have reported the same thing during a dry-air snow storm. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225173 of rec.radio.amateur.antenna Message-ID: <448C37E1.8060002@fuse.net> Date: Sun, 11 Jun 2006 11:33:53 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> Richard Crowley wrote: > "Cecil Moore" wrote ... > >> Dave wrote: >> >>> Methinks your leg was being pulled. >>> >>> The SWR with the apostrophe s is a grammatical error. The apostrophe >>> s indicates that the SWR is possessive, that the SWR owns something; >>> or, that the SWR is doing something. The apostrophe s is not plural!! >> >> >> On the contrary, the plural of the letter A is A's. The plural >> of the number 3 is 3's. It's not too much of a stretch to assume >> that the plural of SWR is SWR's. >> >> From Webster's: "apostrophe - a make used to indicate ... the >> plural of letters or figures." > > > To take the argument well into absurdity (as if it > needed any help), we can discuss whether your > Webster's is descriptive or prescriptive. good one If I can ever help in increasing the absurdity of these newsgroups, I am glad to do so. BTW, all dictionaries are descriptive. Article: 225174 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <1150030449.970907.232220@c74g2000cwc.googlegroups.com> Message-ID: Date: Sun, 11 Jun 2006 15:59:48 GMT w8ji@akorn.net wrote: > People actually seem to think the little particles voving through the > air charge the antenna to a different potential than the air around the > antenna, and that a "dc" path to earth or "dc" path around an element > somehow magically stops RF noise. Let's say we have the following bare-wire dipole system link coupled to the receiver (in fixed font). | | dipole element A link coupled | -////- +--------------------------------------------------///////--+ | +-----------------------------------------------------------+ | | dipole element B | Let's assume one highly charged particle hits dipole element A and transfers half of its charge. Element A will then have an excess charge one half of which will migrate through the link while equalizing the charge between element A and element B. That charge migration/equalization no doubt results in an RF noise pulse. This experiment can easily be performed by anyone. Rub one's leather soles on a wool carpet, touch one side of the dipole, and listen for noise in the receiver. Guaranteed, it will be there. Now multiply the above by millions of charged particles randomly encountering the bare-wire dipole. The charge on each side of the dipole will never be exactly equal. Thus, continuous broad-band noise will be continuously transferred through the link as long as the particles are transferring charge to the antenna. That's what some hams are hearing during dry-air dust and snow conditions. Some have even reported being able to hear individual particle collisions from large snowflakes. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225175 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> Message-ID: Date: Sun, 11 Jun 2006 16:01:25 GMT jawod wrote: > BTW, all dictionaries are descriptive. But all Basic Manuals of Style are prescriptive. Please see my other posting. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225176 of rec.radio.amateur.antenna From: "gravity" References: <44714748_1@news.iprimus.com.au> Subject: Re: highest gain hf antenna in the world Date: Sun, 11 Jun 2006 11:32:01 -0500 Message-ID: <448c4583$0$15725$892e7fe2@authen.yellow.readfreenews.net> "spears" wrote in message news:44714748_1@news.iprimus.com.au... > I was wondering what is the highest gain hf antenna thats operational > anywhere in the world? Secondly what is the gain. > > Peter as others have noted: Arecibo, HAARP, SW curtain arrays. for 20 meters, there have been 48 element Yagi stacks. i'm not aware of any amateur curtain arrays, but several people have modeled these before. you need tall towers, obviously. see the cebik site if you are interested in how curtains work. it would be pretty easy to set a record for ham HF gain using Yagis, rhombics, or curtain array. whether you'd get good performance and a useable beamwidth is another matter. Gravity Article: 225177 of rec.radio.amateur.antenna From: "gravity" References: <44714748_1@news.iprimus.com.au> Subject: Re: highest gain hf antenna in the world Date: Sun, 11 Jun 2006 11:34:11 -0500 Message-ID: <448c4605$0$16435$892e7fe2@authen.yellow.readfreenews.net> "spears" wrote in message news:44714748_1@news.iprimus.com.au... > I was wondering what is the highest gain hf antenna thats operational > anywhere in the world? Secondly what is the gain. > > Peter we have a 3500 foot property line here. i should look into V beams. Gravity Article: 225178 of rec.radio.amateur.antenna From: "DAVID BROWNE" Subject: is this any good Ast6btv mobile ant Message-ID: Date: Sun, 11 Jun 2006 19:18:51 GMT hi is any one useing this ant and what do you think of it Article: 225179 of rec.radio.amateur.antenna From: "Frank's" References: Subject: Re: measurements at the antenna Message-ID: Date: Sun, 11 Jun 2006 20:29:17 GMT > Hi Dan, > > Taking up your postings in reverse order, I can see one problem and > that is emblematic in the question above. Basically it defines a > solution in search of a question. The problem is to figure out what > question you answered by taking the measurements. > > This is not an auspicious beginning. > >>The antenna is a loaded vertical over a set of untuned radials. The feed >>is 50 >>Ohm coax with a 1:1 isolation transformer at the antenna. > >>I intend to run a separate coax for measurement purposes to the feed >>point, > > This single statement introduces too much complexity for your stated > goal of taking measurements. There are rather more conventional ways > to accomplish this. > >>stimulate the antenna >>with a 10 mw signal at the operating frequency, and measure the voltage >>across >>the antenna feed and the ground connection. > > "And ground connection?" If your isolation transformer is working, > there is no need to - unless, of course, you are simply interested in > knowing this fact, or are going to put it to some particular purpose. > However, you are approaching this with no stated purpose, so this > ambiguity is simply accelerating your Drift velocity. > >>Will the voltages indicate the relative RF impedance of antenna (including >>loading coil) versus the ground? > > If you are treating the untuned radials in relation to ground, you > really need to describe ground. It is not so easily achived as > driving a nail into the mud and declaring that's your reference. > >>If the ground were near perfect the voltage at >>the feedpoint should be close to zero. > > "If" comes with magnitudes of error that can only be imagined. From > this point on, you can make your measurements and be guaranteed they > can fit any purpose - "If" you ignore the error. > >>These voltages should indicate the power >>disapation difference between the antenna and the ground. > > They will simply represent the potentials distributed throughout an > imaginary land mine field. Tap dance with care or you may have to > sign off as Stumpy. > > 73's > Richard Clark, KB7QHC Dan, The only way you will get a valid measurement is with your 1:1 transformer, coax, and your vector voltmeter. I guess if you are having problems with the vector voltmeter you can do the same, with less accuracy, using a dual channel scope, and directional coupler. 73, Frank Article: 225180 of rec.radio.amateur.antenna Date: Sun, 11 Jun 2006 15:36:21 -0500 From: Tom Ring Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> Message-ID: <448c7ec6$0$6142$39cecf19@news.twtelecom.net> Ian White GM3SEK wrote: > Tom Ring wrote: > >> w8ji@akorn.net wrote: >> >>> How many Yagi's have floating driven elements without ground paths? >>> >> >> None on VHF/UHF/SHF that I build and anyone I know builds. Maybe on >> HF it's different. I don't know why it should be, though. >> >> Although normally all the other elements float on anything but 6 meters. > > > You're both over-generalizing. In VHF/UHF/SHF yagi construction it's > quite common to find driven elements connected to the boom or floating. > The same choice or a different choice may be made for the parasitic > elements. > > There are many different reasons for these choices, including: > * size of elements and boom > * mechanical strength requirements > * effect of boom on element resonance (depends on mounting method) > * long-term effect stability of element resonance > * feed impedance of driven element (affects choice of feed method) > * number of elements involved > * perceived or actual effects of "static". > > This makes the choices quite complex, and makes generalization > impossible. Quote an example, and someone else will quote you a > counter-example. > > Just one other thing: PLEASE let's not talk about elements being > "grounded", way up there at the top of a tower. > > > Maybe I should have defined what I meant when I said floating. I think we have been talking about a DC grounded element, and that's what I meant with respect to floating. Virtually all of the homebrew yagis that I have seen, and most of the commercial are gamma match, or T match. The gamma is not going to carry the ground through, but is used almost exclusively on 6 meters where driven elements are rarely insulated from the boom. 2 through 432 are T matches and that DC grounds the driven element regardless of how it's mounted. Going up we see mostly loop yagis, and I've never seen one of those that's not grounded. I know there are regular (non-loop) yagis used 902 and up, but I never seen one to see how they are driven. So, for me anyway, the generalization works. And I'm just watching Silverstone, Ian, so don't tell me how it went! tom K0TAR Article: 225181 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <38Wig.44074$4L1.17246@newssvr11.news.prodigy.com> <1150058422.282361.78200@h76g2000cwa.googlegroups.com> Message-ID: Date: Sun, 11 Jun 2006 22:50:24 GMT w8ji@akorn.net wrote: > I don't have a lifetime to spend picking nits with Cecil, but I do > resent his immediate implications I haven't looked at the closely for a > long time. Do you think the people who report the problems that you haven't experienced and don't understand resent your assertion that they believe in magic? The actual magical thinking is asserting that charged particles don't transfer part of their charge to bare wire antennas. > In my experience the vast majority of noise people complain about is > caused by corona from the element or something in the immediate area of > the element. That may be true but we are not discussing corona noise. Exactly where do I go wrong in the following explanation? 1. A highly charged particle encountering one element of a bare copper wire dipole will transfer approximately half its charge to the wire. 2. A charge unbalance between the two elements of a dipole will cause a differential current to flow in a link coupled system. 3. The differential current may be detected by an RF receiver. > Now I'm sure there will be some cases where people disagree with this, > but anyone who can A-B-C test antennas will find that other than a pop > or arc across a dielectric from antennas that accumulate enough charge > to exceed charge leakage the only thing that really matters is how > "pointed" the antenna is and how exposed the points are to the air > around the antenna. This is simply a false statement. Many desert hams, like myself in the 1990's, have experienced another kind of noise. I've never experienced it from snow, but I can understand how it could happen with snow falling through dry air. The snow phenomenon has been reported here on this newsgroup. > All that crud hitting the antenna isn't significantly different in > potential than the air around the element, it just has a lower > impedance. Absolutely false! Charged dust particles are a fact of life in the Arizona desert. There is often not enough moisture in the air to discharge them. Your limited experience is showing. How often does the relative humidity get down to 10% with high winds and dust in Georgia? > As a matter of fact, it is rather silly to claim the particles > discharging make noise and then at the same time claim that a DC path > somehow reduces or eliminates that noise. I didn't claim it "reduces or eliminates that noise". I claimed it eliminates arcing which is certainly a type of noise. > The CLOSER the antenna would > be allowed to float to the potential of the particles the LESS change > in potential would occur. Pulling the element to earth would make each > tiny discharge worse and make more noise, not less. My problem was that 1/2 of the antenna was at DC ground potential and the other half was floating which is typical of a store-bought G5RV. That seems to cause the worst case of arcing. But it is simple physics to realize that each particle acts independently. The charge transfer from each particle causes a tiny differential current between the two elements of the antenna. Millions of unsynchronized collisions per second certainly would produce differential RF noise. A link-coupled balanced dipole system would probably never arc but there would be a differential noise pulse through the receiver as described in the graphic in my other posting. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225182 of rec.radio.amateur.antenna Message-ID: <448CC167.7010009@fuse.net> Date: Sun, 11 Jun 2006 21:20:39 -0400 From: jawod Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <1150030449.970907.232220@c74g2000cwc.googlegroups.com> Cecil Moore wrote: > w8ji@akorn.net wrote: > >Your argument makes perfect sense. Cecil, I was suprised that you actually had arcing to the point of scorched carpet. What voltage do you think this potential represents? Is this a relatively constant voltage. By that, I mean is there usually SOME voltage difference during days or weeks? My naieve question is: Could this serve as a trickle charge for a battery when not used for RX/TX? Article: 225183 of rec.radio.amateur.antenna Message-ID: <448CC4CB.2040308@fuse.net> Date: Sun, 11 Jun 2006 21:35:07 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> > > Possessive is the new standard. > > I get my chops busted if I write with say last year's work instead > of last years work. > > - 73 de Mike KB3EIA - > > I don't understand. Possessive is the new standard? Your chops get busted whey you write "last year's work"? That IS possessive. Article: 225184 of rec.radio.amateur.antenna Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> <448CC4CB.2040308@fuse.net> From: Marco S Hyman Date: 11 Jun 2006 19:28:50 -0700 Message-ID: jawod writes: > I don't understand. Possessive is the new standard? Your chops get busted > whey you write "last year's work"? > That IS possessive. Is it? I've always wondered. Does the work "belong" to last year? Does last year "own" the work? It's *my* work that was done last year. Curious, // marc Article: 225185 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Noise level between two ant types References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <38Wig.44074$4L1.17246@newssvr11.news.prodigy.com> <1150058422.282361.78200@h76g2000cwa.googlegroups.com> <1150076986.983597.21920@c74g2000cwc.googlegroups.com> Message-ID: Date: Mon, 12 Jun 2006 04:17:25 GMT w8ji@akorn.net wrote: > You can a call me a liar if you like, but it doesn't change the facts. Being ignorant doesn't make you a liar. The fact is that many hams have experienced charged particle noise. Your denial of such doesn't change the known facts. The meaning of most of your posting escapes me so I will just summarize my position. When I lived in the Arizona, clear-sky wind-driven charged dust particles transferred lots of energy to my bare-wire G5RV. It caused arcing whether the outside braid was grounded or not. It only happened when the wind was blowing and the humidity was very low. I'm not sure what your point of disagreement is so help me out. Do you agree that a charged particle will transfer energy to the bare wire in a dipole when it touches it? If not, why not? If the antenna were link coupled, do you agree that the above transferred energy will try to equalize between the two dipole elements? If not, why not? Do you agree that the equalizing of the charges between elements would cause a current to flow through the link? If not, why not? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225187 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Message-ID: Date: Sun, 11 Jun 2006 21:54:02 -0700 "Mike Coslo" wrote in message news:AbqdnfZu6_9jKhHZnZ2dnUVZ_qudnZ2d@adelphia.com... > > I get my chops busted if I write with say last year's work instead of > last years work. > > - 73 de Mike KB3EIA - 1. Too bad you have to work for/with people like that. " ... last year's work" is correct. The possessive does not exclusively denote ownership. It also denotes the "of or pertaining to" relationship, as in "Cleveland's bus system." 2. I just went to the McGraw-Hill Learning Center http://highered.mcgraw-hill.com/sites/076743000x/student_view0/chapter1/apos trophes.html and took their apostrophe quiz Results Reporter Out of 17 questions, you answered 17 correctly, for a final grade of 100%. 17 correct (100%) 0 incorrect (0%) 0 unanswered (0%) Here's the most interesting one: Last years womens softball team is much better than this years. [The stem omits apostrophes.] C) Last year's women's softball team is much better than this year's. Feedback: Correct! 3. Despite the absolute correctness of the apostrophe for the plural of numbers and letters, I see a lot of acronyms and abbreviations made plural by the addition of an "s" without the apostrophe and I don't flinch. I think the language is evolving regarding acronyms, which, after all, are less than 100 years old. Therefore, I vote to accept "SWRs." 73, "Sal" (KD6VKW) Article: 225188 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <448B2227.2090601@fuse.net> Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Message-ID: <4H6jg.28755$QP4.3723@fed1read12> Date: Sun, 11 Jun 2006 22:10:23 -0700 "jawod" wrote in message news:448B2227.2090601@fuse.net... < snip > I really can't relate to the impossibility > of the task. Don't know how THIS old dog would do with a new trick. I have a similar inability to relate, but it has to do with math. Most of it I ever studied came easily to me. However, some poor souls cannot regard simple real life situations in terms of math. For example, E-max for my lovely bride is the checkbook. That's it. [How many square yards in a 9 x 12 foot carpet? Duh - what color is it?] I learn new tricks every day. Morse Code isn't one of them. Article: 225189 of rec.radio.amateur.antenna From: "Jeff" Subject: Re: Wide bandwidth ladder line J-pole for 6-Meters Date: Mon, 12 Jun 2006 08:05:42 +0100 Message-ID: References: <5ZWdnbe8ZP27NBHZnZ2dnUVZ_vudnZ2d@comcast.com> Have you not just re-invented the 'Slim Jim'?? 73 Jeff "Chuck Olson" wrote in message news:5ZWdnbe8ZP27NBHZnZ2dnUVZ_vudnZ2d@comcast.com... > I've been working on a ladder line J-Pole design for 6m, but have had very > little luck until today. The problem has been critical tuning and narrow > SWR > bandwidth. The improvement came today when I implemented an idea I had > concerning the severed piece of wire that "just goes along for the ride" > in > the ladder line after cutting the 1/4" gap for the 1/4-wave shorted stub. > I > figured that many successful 50 MHz J-Poles are made from copper tubing > because the thicker elements give it good bandwidth. My idea was to make > use > of the extra wire and connect it at top and at the gap to the radiator > side, > making the half-wave radiator act as a much thicker element. My 2:1 > bandwidth went from 300 KHz to 2 MHz. > > The resulting antenna design is very straightforward, using the Velocity > Factor of 0.91 for the 1/4-wave stub and 0.95 for the radiator. This > essentially sets the radiator length equal to the standard 468/F dipole > length. If you analyze the operation of the very successful "Open Stub > J-Pole" that Arrow makes, you will find they use the 0.95 FV for both the > radiator and the stub, which is appropriate in their open design. So that > pointed me in that direction as far as cutting lengths are concerned. The > only remaining question was the location of the feed tap for 50-ohm cable. > I > used alligator clips on the coax to find the best position, and that > turned > out to be 4 3/8" up from the shorted bottom end, with the shield going to > the gap side. My rig sees a 1:1 SWR from 50.0 to 51.2 MHz, and it gets to > 1.6:1 at 52.1 MHz. With this information, it should be easy to design one > that takes full advantage of the antenna's bandwidth to provide operation > over the widest segment of the 6M band. > > My intuition told me that there should be some advantage to using 450-ohm > ladder line compared to 300-ohm twinlead. Maybe this extra bandwidth is > it. > > 73, > > Chuck, W6PKP > > Article: 225190 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: measurements at the antenna Date: Mon, 12 Jun 2006 02:19:45 -0700 Message-ID: <128qcdkbphel65f@corp.supernews.com> References: <7l0q82l2ap9uosqrvi59bi2ib6484haeme@4ax.com> In addition to the weaknesses of scope probes mentioned by Richard is the ground lead. Even a short one has considerable reactance at VHF, and its use will promote common mode current on the outside of the probe cable. Any decent scope measurement at very high frequencies is done with an adapter which connects directly to the ground ring near the end of the probe, through a very short conductor. An example is the one sold by Tektronix, P/N 013-0085-00 the last time I checked. Even it must be used with some care. I don't see any hope in your making meaningful measurement with the setup you describe -- there are too many potential sources of serious error. Roy Lewallen, W7EL Article: 225191 of rec.radio.amateur.antenna Message-ID: <448D5FF7.4040907@fuse.net> Date: Mon, 12 Jun 2006 08:37:11 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> <448CC4CB.2040308@fuse.net> Marco S Hyman wrote: > jawod writes: > > >>I don't understand. Possessive is the new standard? Your chops get busted >>whey you write "last year's work"? >>That IS possessive. > > > Is it? I've always wondered. Does the work "belong" to last year? > Does last year "own" the work? It's *my* work that was done last year. > > Curious, > > // marc yes at least to me "last year's work" as opposed to some other "year's work" pretty sure that's possessive John Article: 225192 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> <448CC4CB.2040308@fuse.net> <448D5FF7.4040907@fuse.net> Message-ID: Date: Mon, 12 Jun 2006 12:49:39 GMT jawod wrote: > yes at least to me "last year's work" as opposed to some other > "year's work" pretty sure that's possessive A year is an it. Is it possessive because it's its work? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225193 of rec.radio.amateur.antenna From: "gravity" Subject: hey W8JI Date: Mon, 12 Jun 2006 07:57:41 -0500 Message-ID: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> why do dislike 5/8 wave antennas? can you point me to any references. i realize there is a high lobe. i have an old Low Band Dxing, and ON4UN seems to like 5/8 on 40. i personally tried a 5/8 vertical on 10 with bad results. however, my ground system was terrible. i plan to try 5/8 with full 120 * 1/2 wave radials. i remember at one multi-single, we had a 1/4 wave 10 meter at 100 feet that was even with the beams sometimes. i believe K3LR mentioned he was building a 10 meter 5/8 wave 4 square. was he kidding? Gravity Article: 225194 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 08:00:17 -0500 Message-ID: <448d653c$0$84074$892e7fe2@authen.yellow.readfreenews.net> one thing i've been pondering is a vertical colinear. 1/2 wave over 1/2 wave. i have not modeled it. is there any free modeling software? i noticed that you stated that phased arrays with elements separated by more than 2 waves don't work well. i was thinking of a vertical array, either inline or broadside. Gravity Article: 225195 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 08:04:28 -0500 Message-ID: <448d6637$0$80513$892e7fe2@authen.yellow.readfreenews.net> just some random thoughts: a ground system for 10 meter 4-square would be 240 waves worth of wire (minus some because of shared radials). that's 8000 feet, at 5 cents a foot, $200. you can set up a beam at 30 feet for that price. scaling up to 40 meters, that's a lot of wire. Gravity Article: 225196 of rec.radio.amateur.antenna Date: Mon, 12 Jun 2006 07:47:36 -0600 From: hayseed Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> Message-ID: <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> Everybody is correct and everybody is wrong. According to Turabian's "A Manual for Writers", plurals of most single and multiple capital letters used as nouns are formed by adding "s" alone. Example: SWRs Form the plural of small letters, capital letters with periods, and capital letters that would be confusing if "s" alone were added by adding apostrophe and "s". Now, everybody, back to work and mind your p's and Qs 73 Article: 225197 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: RF grounding methods for sailboats: A Summary Date: Mon, 12 Jun 2006 10:28:45 -0400 Message-ID: References: <1148994725_36063@sp6iad.superfeed.net> <6ggr72509n8k0ulii7a3j574e6ogiuhrbp@4ax.com> <1149107678_2377@sp6iad.superfeed.net> <447ec69c_1@news.iprimus.com.au> <128278grmhthsab@corp.supernews.com> <1288u8idqtf9b0a@corp.supernews.com> <06WdndDEvojgWRHZnZ2dnUVZ_o-dnZ2d@adelphia.com> <5d3q82tp0vta4mu3i4843sqts18j86ota9@4ax.com> Richard Clark wrote: > On Sun, 11 Jun 2006 21:33:51 -0400, Mike Coslo > wrote: >> the original poster spoke of a hypothetical wire >> not working at 4 feet underwater. > > Hi Mike, > > This hypothesis was a home-grown and hand rolled fantasy. > >> I don't doubt that the problem has been solved (if it exists in the >> first place). > > Oh, there is a problem alright: Making the lesson penetrate a quarter > inch of skull with more success than RF struggling through an > imaginary 4 foot skin depth of water problem. Which won't happen until we discuss this into showing how it is impossible to put a radio on a ship! hehehe 8^) - 73 de Mike KB3EIA - Article: 225198 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Have any of you mailed this to your ARRL Division directors and Date: Mon, 12 Jun 2006 11:00:34 -0400 Message-ID: References: <448B2227.2090601@fuse.net> <4H6jg.28755$QP4.3723@fed1read12> Sal M. Onella wrote: > "jawod" wrote in message news:448B2227.2090601@fuse.net... > > < snip > > > I really can't relate to the impossibility >> of the task. Don't know how THIS old dog would do with a new trick. > > I have a similar inability to relate, but it has to do with math. Most of > it I ever studied came easily to me. However, some poor souls cannot regard > simple real life situations in terms of math. For example, E-max for my > lovely bride is the checkbook. That's it. [How many square yards in a 9 x > 12 foot carpet? Duh - what color is it?] > > I learn new tricks every day. Morse Code isn't one of them. The real issue is probably that HF privileges are probably just not that important to you. I have enough hearing problems that learning Morse was darn hard. 60-70 db tinnitus, (est) and hearing holes in the higher frequencies, and just can't hear for crap. When I got my Tech license, a lot of people told me that "Morse code is going away any day now, no need to learn that stuff". I'm glad I didn't listen to them - I have had HF access for 6 years now, and if learning Morse was the price I had to pay, then it was worth it. YMMV Since it may be a couple years more until the Morse code test is eliminated (if even then) my decision is looking better all the time. - 73 de Mike KB3EIA - Article: 225199 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Buyer Beware - Cobra Ultralight Date: Mon, 12 Jun 2006 11:04:37 -0400 Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <9luj82h4k68g3r71qm0c4qd3ijie9pk4ei@4ax.com> Owen Duffy wrote: > On Fri, 09 Jun 2006 15:33:59 GMT, Cecil Moore > wrote: > > >> One thing interesting about the Cobra-Jr is that if it is >> made 62 feet long instead of 73 feet long, it becomes >> resonant around 3.85 MHz with a feedpoint impedance of >> about 16 ohms. That's an SWR of only about 3:1 on coax. >> or ~1.3:1 using a 1:4 balun. That's a half size antenna >> for 75m that is only about 1.5 dB down from a full size >> 1/2WL dipole. > > Where are you observing resonance? > > I created a model with ~73' length that does resonate (low Z) at the > dipole centre around 3.6MHz. Other factors affect resonance a little, > but you may want to check your model to see it is laid out properly > and connected up properly. I'm modeling the thing in 4nec2 now. I get different results than both of you, so I need to go back to the drawing board..... I've always wondered though if some mfgr's fudge a little on their lengths to cloud the issue a bit. But then I make my antennas, so I never bought one to check. - 73 de mike KB3EIA - Article: 225200 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Mon, 12 Jun 2006 10:58:30 -0500 Message-ID: <128r3pa74ftgdb8@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> hayseed wrote: > Everybody is correct and everybody is wrong. > > According to Turabian's "A Manual for Writers", plurals of most single > and multiple capital letters used as nouns are formed by adding "s" > alone. Example: SWRs > Form the plural of small letters, capital letters with periods, and > capital letters that would be confusing if "s" alone were added by > adding apostrophe and "s". > > Now, everybody, back to work and mind your p's and Qs > > 73 My question is: just what is/are "SWR's" and "SWRs" Dave WD9BDZ Article: 225201 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: hey W8JI References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <448d653c$0$84074$892e7fe2@authen.yellow.readfreenews.net> Message-ID: Date: Mon, 12 Jun 2006 17:11:42 GMT gravity wrote: > one thing i've been pondering is a vertical colinear. 1/2 wave over 1/2 > wave. i have not modeled it. > > is there any free modeling software? You can use the free demo copy of EZNEC by driving the collinear with two sources and varying the phase angle between them. Then you can design an appropriate phasing network. I don't think the lumped inductive reactance available in EZNEC will yield an accurate phase shift and the free demo will not handle enough segments to model a helical coil. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225202 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: hey W8JI References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <448d6637$0$80513$892e7fe2@authen.yellow.readfreenews.net> Message-ID: Date: Mon, 12 Jun 2006 17:13:54 GMT gravity wrote: > just some random thoughts: > > a ground system for 10 meter 4-square would be 240 waves worth of wire > (minus some because of shared radials). that's 8000 feet, at 5 cents a > foot, $200. you can set up a beam at 30 feet for that price. Or how about a 10m rotatable EDZ? No radials required. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225203 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> Message-ID: Date: Mon, 12 Jun 2006 17:20:40 GMT hayseed wrote: > Now, everybody, back to work and mind your p's and Qs As in words like, "amen", are pronounced "ah". That certainly seems confusing to me and the confusion is not apparent until more than halfway through the sentence. A's in words like, "amen", are pronounced "ah". No confusion there. -- 73, Cecil http://www.qsl.net/w5dxp Article: 225204 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> Message-ID: <2Rhjg.43959$fb2.30213@newssvr27.news.prodigy.net> Date: Mon, 12 Jun 2006 17:51:58 GMT Cecil Moore wrote: ... > > A's in words like, "amen", are pronounced "ah". > ... Not where I come from. 73, Tom Donaly, KA6RUH Article: 225205 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> <2Rhjg.43959$fb2.30213@newssvr27.news.prodigy.net> Message-ID: <5Qijg.43979$fb2.36034@newssvr27.news.prodigy.net> Date: Mon, 12 Jun 2006 18:59:13 GMT Tom Donaly wrote: > Cecil Moore wrote: >> A's in words like, "amen", are pronounced "ah". > Not where I come from. I know hillbillies still use the long 'A'. :-) Did you know that when Jesus prayed to God in Aramaic, he probably prayed to "Allah"? -- 73, Cecil http://www.qsl.net/w5dxp Article: 225206 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: I bought a large capacitance hat for my vertical, but the antenna Date: Mon, 12 Jun 2006 14:11:27 -0500 Message-ID: <128rf327u816lb1@corp.supernews.com> References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> Cecil Moore wrote: > hayseed wrote: > >> Now, everybody, back to work and mind your p's and Qs > > > As in words like, "amen", are pronounced "ah". > > That certainly seems confusing to me and the confusion > is not apparent until more than halfway through the > sentence. > > A's in words like, "amen", are pronounced "ah". > > No confusion there. How about IDEA pronounced "IDEer" Article: 225207 of rec.radio.amateur.antenna From: "K. Hastings" Subject: 2 Meter QUAD - Balun / SWR question Message-ID: Date: Mon, 12 Jun 2006 19:17:44 GMT I recently built a decent 3-element 2 M Quad that fits inside my insulated attic (just barely) and is all connected to my shack. Worked great... The problem now is that the SWR is very high (>>3:1) on all freqs above the 145 MHz channels. I think that the Quad, when tested inside the house had a great match across the band from what I recall. This thing is fed with RG-8 and I purposely put a whole bunch of turns into a 5" coil near the feed point, and I'm wondering if I should have done that at all now. I'm sure that the match would be different regardless since it's now located in a different space, and I understand how that can change things. It's dark and itchy up there - before I go up there and unwind the whole BALUN, can you guys tell me whether or not I even need that thing, or have I got another problem. FWIW it works great - decent gain and nicely directional - but the SWR is too high, and it resets all the programmable thermostats clocks in the house when I key up (interesting RFI huh?) which my attic ground-plane DOES NOT do. help? Kevin VE9-XYZ myfamilydotcom@hotmail.com Article: 225208 of rec.radio.amateur.antenna From: "Jimmie D" References: Subject: Re: FM without 'pink noise' Message-ID: Date: Mon, 12 Jun 2006 15:28:38 -0400 "Boborato" wrote in message news:e6e4u3$jel$1@news.nivel5.cl... > Hi group. > > I wanna know how can I get the FM signal without that nasty 'pink' noise. > > I'm not using any kind of external antenna. > > Greetings!! > Use an outside antenna Article: 225209 of rec.radio.amateur.antenna From: Telamon Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> <128rf327u816lb1@corp.supernews.com> Message-ID: Date: Mon, 12 Jun 2006 19:34:47 GMT In article <128rf327u816lb1@corp.supernews.com>, "David G. Nagel" wrote: > Cecil Moore wrote: > > > hayseed wrote: > > > >> Now, everybody, back to work and mind your p's and Qs > > > > How about dropping rec.radio.shortwave from the news group list. Thanks in advance. -- Telamon Ventura, California Article: 225210 of rec.radio.amateur.antenna From: Telamon Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> <128rf327u816lb1@corp.supernews.com> Message-ID: Date: Mon, 12 Jun 2006 20:38:44 GMT In article , Cecil Moore wrote: > David G. Nagel wrote: > > How about IDEA pronounced "IDEer" > > Y'all from Boston? No. How about dropping rec.radio.shorwave from the thread. Thanks in advance. -- Telamon Ventura, California Article: 225211 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: FM without 'pink noise' Message-ID: <3fkr82hl0ugon8vrja2r6bt8dpj2c5cna9@4ax.com> References: Date: Mon, 12 Jun 2006 21:10:04 GMT Neat. I especially like the Black Noise... On Sat, 10 Jun 2006 08:08:24 -0500, "TSnCS" wrote: >http://en.wikipedia.org/wiki/Pink_noise > >Then compare to http://en.wikipedia.org/wiki/White_noise > John Ferrell W8CCW Article: 225212 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <1149817448.339895.295850@u72g2000cwu.googlegroups.com> <3G4ig.48095$Lm5.9297@newssvr12.news.prodigy.com> Date: Mon, 12 Jun 2006 21:10:04 GMT My trip down that road was called a "Gotham Vertical". What it lacked in performance, it made up for in education! Google it for an evening of fun reading... de W8CCW John On Fri, 09 Jun 2006 02:03:43 GMT, Cecil Moore wrote: >w8ji@akorn.net wrote: >> The problem is that antenna is advertised to work all bands. >> Unfortunately it doesn't do very well on many bands. > >Sounds like a G5RV. John Ferrell W8CCW Article: 225213 of rec.radio.amateur.antenna From: cq-dx@arrl.net (New Ham) Subject: Re: I bought a large capacitance hat for my shortwave antenna, but the antenna still gets wet when it rains. Message-ID: References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> <128rf327u816lb1@corp.supernews.com> Date: Mon, 12 Jun 2006 21:25:03 GMT In article , Telamon wrote: >In article <128rf327u816lb1@corp.supernews.com>, > "David G. Nagel" wrote: > >> Cecil Moore wrote: >> >> > hayseed wrote: >> > >> >> Now, everybody, back to work and mind your p's and Qs >> > >> > > >How about dropping rec.radio.shortwave from the news group list. > >Thanks in advance. > >-- >Telamon >Ventura, California Did I get ripped off? Article: 225214 of rec.radio.amateur.antenna From: "Jerry Martes" References: Subject: Re: 2 Meter QUAD - Balun / SWR question Message-ID: Date: Mon, 12 Jun 2006 21:46:31 GMT "Richard Clark" wrote in message news:v7ir82lfd6dtckmrvl3dsuavgrd1cqn0cs@4ax.com... > On Mon, 12 Jun 2006 19:17:44 GMT, "K. Hastings" >>I think that the Quad, when tested inside the house had a great match >>across >>the band from what I recall. > > Hi Kevin, > > You have just defined its environment. > >>This thing is fed with RG-8 and I purposely put a whole bunch of turns >>into >>a 5" coil near the feed point, and ... it resets all the programmable >>thermostats clocks in the house >>when I key up (interesting RFI huh?) > > Do you find the hidden clue when all the excess verbiage is cleared > away? > > A whole bunch of turns is not very specific except to indicate you > probably overdid it and negated any benefit you might have expected. > Would it help to say fewer turns on a smaller form? > > That, however, is probably not what is responsible for the SWR. You > are going to have to tune the antenna in place AFTER you successfully > isolate the drive line. > > 73's > Richard Clark, KB7QHC Hi Richard As you know, I have been getting good results with the high permeability ferrite tubes for decoupling the coax feed line on my balanced antenna. I bought a bunch of inexpensive ferrites that were intended for absorbing RFI, >from All Electronics. Would it be practical for Kevin, the orginal poster, to get decent results with a few ferrites covering the coax where it seperates from the boom?? Jerry Article: 225215 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Buyer Beware - Cobra Ultralight Message-ID: References: <1149770557.629987.141180@i40g2000cwc.googlegroups.com> <9luj82h4k68g3r71qm0c4qd3ijie9pk4ei@4ax.com> Date: Mon, 12 Jun 2006 21:59:14 GMT On Mon, 12 Jun 2006 11:04:37 -0400, Michael Coslo wrote: > I'm modeling the thing in 4nec2 now. I get different results than both >of you, so I need to go back to the drawing board..... The NEC deck for my models is linked from the article. You will need to replace the $freq symbolic variable though with a number. Owen -- Article: 225216 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <1149910151.859293.41560@j55g2000cwa.googlegroups.com> <1149976606.648802.136670@j55g2000cwa.googlegroups.com> <9aJig.94798$H71.24853@newssvr13.news.prodigy.com> <1149993717.760844.168170@g10g2000cwb.googlegroups.com> <448b88ac$0$76686$39cecf19@news.twtelecom.net> <38Wig.44074$4L1.17246@newssvr11.news.prodigy.com> <1150058422.282361.78200@h76g2000cwa.googlegroups.com> <1150076986.983597.21920@c74g2000cwc.googlegroups.com> Subject: Re: Noise level between two ant types Message-ID: Date: Mon, 12 Jun 2006 18:52:29 -0400 "Cecil Moore" wrote in message news:pV5jg.146628$F_3.104553@newssvr29.news.prodigy.net... > w8ji@akorn.net wrote: >> You can a call me a liar if you like, but it doesn't change the facts. > > Being ignorant doesn't make you a liar. The fact is that > many hams have experienced charged particle noise. Your > denial of such doesn't change the known facts. > > The meaning of most of your posting escapes me so I will > just summarize my position. > > When I lived in the Arizona, clear-sky wind-driven charged > dust particles transferred lots of energy to my bare-wire > G5RV. It caused arcing whether the outside braid was grounded > or not. It only happened when the wind was blowing and > the humidity was very low. > > I'm not sure what your point of disagreement is so help > me out. > Youze guyz are arguing about two cases of "arcing" and going off on tangents. First case is as Cecil has experienced and 'splained, is the static electricity charge buildup and corresponding noise/discharge on conducting "things" due to charged particles - aka rubbing the glass rod with furry animal coat. The part (antenna) gets charge from the "rubbing" by the particles, air, whatever...., builds up voltage and is looking for discharge across anything that provides jumping points for the voltage accumulated. This is the case of clear Arizona skies, with no clouds in sight, just wind doing it's "thing". W8JI might not believe it, but it IS the fact. Second case is, as it was hotly discussed on Contest and other reflectors, and first mentioned by VE3BMV, W0UN, W4ZV and others, in conjunction with lightning and protection against it - is the static electricity charge buildup due to the clouds "rubbing" in the air and creating huge static charge between the clouds and the earth ground and objects "residing" on ground and connected to it. There the highest , mostly grounded, objects get "first crack" at the "touching" the voltage gradient generated by the static electricity buildup. If there is a sharp object, it will start "acting" by generating corona and "peacefully" discharging the potential. If it can't keep up with rate of "peaceful" charge, it will invite lightning strike. The corona can be visible at the times, or it doesn't have to be. Then we get cases when the high antenna is the highest object and will be the "discharger" and the noisiest one. That appears to discharge the charge >from the area (space) in the vicinity of the high (object) antenna - umbrella. You can look at it as a capacitor plate, collecting charge from the space around it. Lower antennas get benefit of discharged space and are quiet. This is especially noticeable with stacked antennas. The top one would be typically 20/9 noise - hash, the lower one would be dead quiet. The same then applies when you have higher object than antenna in question, that antenna could be quiet, but when (beam) is aimed at the higher object (the static discharger) it can receive noise, but at much lower strength. This umbrella effect seems also work as a lightning prevention by discharging the space in the vicinity of the structure and preventing critical buildup of voltage causing creating of leader and inviting lightning strike (99.9%). I and others have noticed practical elimination of lightning strikes to our installation when sporting tall, grounded towers with large antennas (capacitor plates). They seem to bleed the deadly potential from the air "sandwich" between the sky (clouds) and ground and objects under the "umbrella" and making lightning look at pointy grounded objects before and after our "ugly" antennas and discharge their deadly megawatts there. So large antennas on tall towers - GOOD to repell lightning. Pointy, sharp objects - BAAAAD, they attract lightning. So, one can protect his QTH and radio junk by either inviting lightning to strike the lightning arresters and hopefully conduct them to ground, or better, repelling it by the Antenna Umbrella - the biggest mother antenna (capacitor plate) on the tallest possible and well grounded tower (no protruding VHF vertical pointy junk above) you can put up. Scientwists might not find this believable, but those with big towers and large grounded antennas noticed remarkable absence of direct lightning strikes vs. when previously sporting pointy verticals or towers without antennas on the top. When I had my TH6 at 60 ft. and above it, way up 2m Ringo Ranger on a mast, I got visited by direct lightning trice within 2 years. When put up Big Bertha with 60 ft boom Razors, never again over 10 years. Not very statistically scientific, but very noticeable. Same experienced by W0UN, W0ZV and others. Soooo, the judge's verdict is: Cecil is right, W8JI is partially right, jury to judge by the above 'splanation of this humble servant. :-) I hope this clears some static static. -- Yuri Blanarovich, K3BU, VE3BMV Article: 225217 of rec.radio.amateur.antenna From: Bruce in Alaska Subject: Re: RF grounding methods for sailboats: A Summary References: <1148994725_36063@sp6iad.superfeed.net> <6ggr72509n8k0ulii7a3j574e6ogiuhrbp@4ax.com> <1149107678_2377@sp6iad.superfeed.net> <447ec69c_1@news.iprimus.com.au> <128278grmhthsab@corp.supernews.com> <1288u8idqtf9b0a@corp.supernews.com> <06WdndDEvojgWRHZnZ2dnUVZ_o-dnZ2d@adelphia.com> Message-ID: Date: Mon, 12 Jun 2006 22:57:00 GMT In article <06WdndDEvojgWRHZnZ2dnUVZ_o-dnZ2d@adelphia.com>, Mike Coslo wrote: > I'm not so sure the exact size ship we speak of. But if you recall back > a long time ago when the original poster spoke of a hypothetical wire > not working at 4 feet underwater. I even suspect that a 30 foot vessel > might take greater than a 4 foot excursion, especially in your neck of > the woods! It really doesn't matter if the vessel has a draft of 4 feet or 24 feet,as the coupling to the seawater is to the hull/water boundry which is the same as the surface of the water from the RF point of view. Skin Effect, or Skin Depth @ any frequency is a Surface Effect and that surface is the hull/water boundry, for any hull material. Bruce in alaska -- add a <2> before @ Article: 225218 of rec.radio.amateur.antenna Message-ID: <448DF326.1090300@fuse.net> Date: Mon, 12 Jun 2006 19:05:10 -0400 From: jawod Subject: Re: I bought a large capacitance hat for my vertical, but the antenna References: <1149714609.565540.160300@c74g2000cwc.googlegroups.com> <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <128n7597b11m190@corp.supernews.com> <448C37E1.8060002@fuse.net> <448CC4CB.2040308@fuse.net> <448D5FF7.4040907@fuse.net> Cecil Moore wrote: > jawod wrote: > >> yes at least to me "last year's work" as opposed to some other >> "year's work" pretty sure that's possessive > > > A year is an it. Is it possessive because it's its work? How did this get started? :) Whose on first? No answer on the antenna trickle charger? From Thierry Tue Jun 13 01:36:57 EDT 2006 Article: 225219 of rec.radio.amateur.antenna From: Newsgroups: rec.radio.amateur.antenna Subject: tri-band HF beam for portable ops ? Date: Tue, 13 Jun 2006 01:09:05 +0200 Lines: 25 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-RFC2646: Format=Flowed; Original NNTP-Posting-Host: ip-88-207-129-40.tvsurf.pt.lu Message-ID: <448df40f$1@news.vo.lu> X-Trace: news.vo.lu 1150153743 88.207.129.40 (13 Jun 2006 01:09:03 +0200) Path: news.unc.edu!elk.ncren.net!news2.wam.umd.edu!bloom-beacon.mit.edu!npeer.de.kpn-eurorings.net!news.vo.lu!not-for-mail Xref: news0.isis.unc.edu rec.radio.amateur.antenna:225219 Hi, I am interested in buying a triband yagi (20-15-10) for portable operations But I suspect such antennas, most being made of aluminium, to be heay (over 10 kg) and maybe not easy to dismantle regularly I review on my webiste various portable configurations, so I know quite well the problem. I would like to know if some of you have testes successfully such installations using the minimum of hardware (transportation using an ordinary car, not a break, not a pickup and not a 4x4, installation by only one person, small beam placed on a single pod 8-10m high, one guy-wire, no rotator) for a on-day activity, the Tx working on battery. If you work in the field with a small beam, what difficilty do you experimented (weght, wingspan, other)? Thanks Thierry ON4SKY, LX4SKY http://www.astrosurf.org/lombry/menu-qsl.htm Article: 225220 of rec.radio.amateur.antenna From: "Jerry Martes" References: Subject: Re: 2 Meter QUAD - Balun / SWR question Message-ID: Date: Mon, 12 Jun 2006 23:40:19 GMT "Richard Clark" wrote in message news:sqor82tt9rminjmmc5ocs406n8j321btol@4ax.com... > On Mon, 12 Jun 2006 21:46:31 GMT, "Jerry Martes" > wrote: >> Hi Richard >> >> As you know, I have been getting good results with the high permeability >>ferrite tubes for decoupling the coax feed line on my balanced antenna. >>I >>bought a bunch of inexpensive ferrites that were intended for absorbing >>RFI, >>from All Electronics. Would it be practical for Kevin, the orginal >>poster, >>to get decent results with a few ferrites covering the coax where it >>seperates from the boom?? > > Hi Jerry, > > Sure, but you have the advantage of being able to measure the Z of > those ferrites. However, buying them rummage style and hoping they > will work does not always bring a satisfactory solution. > > 73's > Richard Clark, KB7QHC Hi Richard I realize that I place way more emphasis on "Amateur" in the HAM concept. I'm not inclined to depend on using only the best component. But, it seems that any of those ferrite tubes that were intended to be used to minimize RFI will work well at 144 MHz. So, since they are cheap and available, I thought it might be worth trying some inexpensive, high permeability tubes instead of coiling the coax into a coil. I did measure the impedance across a loop of RG 223 with 4 tubes around the outside. The problem I come up with is my ignorance of *whats needed* for adequate decoupling of the balanced antenna from the outside of the coax. I depend on you to shed light on alot of the things I try. Jerry Article: 225221 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <1150153471.710936.106120@j55g2000cwa.googlegroups.com> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 21:19:01 -0500 Message-ID: <448e2070$0$16391$892e7fe2@authen.yellow.readfreenews.net> W8JI, thanks for your comments. i must have missed that cebik article, so i will read it. now i reread the antenna section of ON4UN's book, and he does say 5/8 wave are best for very poor or very good (saltwater) ground. so i am probably wasting my time with 5/8 waves, although i will try it for the hell of it. i bet ON4UN used a 5/8 on 40 because he needed the length for 160 and 80 in the multiband vertical. hmm. Gravity Article: 225222 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <448d6637$0$80513$892e7fe2@authen.yellow.readfreenews.net> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 21:21:19 -0500 Message-ID: <448e20fa$0$16322$892e7fe2@authen.yellow.readfreenews.net> "Cecil Moore" wrote in message news:mhhjg.23801$VE1.12511@newssvr14.news.prodigy.com... > Or how about a 10m rotatable EDZ? No radials required. this is a good idea. cebik site has some articles about EDZ beams and colinears and arrays. i should probably go with a 4 element 10 meter Yagi, but i want to experiment with some alternatives. Gravity Article: 225223 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <448d653c$0$84074$892e7fe2@authen.yellow.readfreenews.net> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 21:21:53 -0500 Message-ID: <448e211c$0$16324$892e7fe2@authen.yellow.readfreenews.net> "Bob Bob" wrote in message news:bqc0m3-6jq.ln1@p400bob.personal.cox.net... > 4NEC2? > > http://home.ict.nl/~arivoors/Home.htm thanks Bob. that looks like it may do the trick. Gravity Article: 225224 of rec.radio.amateur.antenna From: "gravity" References: <448d64a0$0$16401$892e7fe2@authen.yellow.readfreenews.net> <448d653c$0$84074$892e7fe2@authen.yellow.readfreenews.net> Subject: Re: hey W8JI Date: Mon, 12 Jun 2006 21:22:20 -0500 Message-ID: <448e2137$0$79450$892e7fe2@authen.yellow.readfreenews.net> "Cecil Moore" wrote in message news:ifhjg.23800$VE1.2929@newssvr14.news.prodigy.com... > gravity wrote: > > one thing i've been pondering is a vertical colinear. 1/2 wave over 1/2 > > wave. i have not modeled it. > > > > is there any free modeling software? > > You can use the free demo copy of EZNEC by driving the > collinear with two sources and varying the phase angle > between them. Then you can design an appropriate phasing > network. I don't think the lumped inductive reactance > available in EZNEC will yield an accurate phase shift > and the free demo will not handle enough segments to > model a helical coil. > -- thanks, that plus the program Bob mentioned may get me started in modeling. Gravity > 73, Cecil http://www.qsl.net/w5dxp Article: 225225 of rec.radio.amateur.antenna From: howard@hisisp.com Subject: Re: I bought a large capacitance hat for my vertical, but the antenna still gets wet when it rains. Date: Mon, 12 Jun 2006 19:22:12 -0700 Message-ID: <578s82da5ulf6f0d41hs3vrvu1rnsveqk0@4ax.com> References: <448767E7.4040009@fuse.net> <1149774341.518961.129650@i40g2000cwc.googlegroups.com> <1149939299.081665.138120@m38g2000cwc.googlegroups.com> <448d6fe1$0$23707$a82e2bb9@reader.athenanews.com> <2Rhjg.43959$fb2.30213@newssvr27.news.prodigy.net> <5Qijg.43979$fb2.36034@newssvr27.news.prodigy.net> On Mon, 12 Jun 2006 18:59:13 GMT, Cecil Moore wrote: >Tom Donaly wrote: > >> Cecil Moore wrote: >>> A's in words like, "amen", are pronounced "ah". > >> Not where I come from. > >I know hillbillies still use the long 'A'. :-) >Did you know that when Jesus prayed to God in >Aramaic, he probably prayed to "Allah"? Yes on Aramaic, however Jesus prayed to the same G-d as the Jews of that time did..........albeit in a somewhat different fashion. Article: 225226 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: H FIELD ANTENNAS? References: <1149531001.503023.220830@g10g2000cwb.googlegroups.com> <1149542340.997313.268380@h76g2000cwa.googlegroups.com> <128bhjj6t6a6jb9@corp.supernews.com> <1149626355_40043@sp6iad.superfeed.net> <1149628313.756125.321140@j55g2000cwa.googlegroups.com> <1149640742_42035@sp6iad.superfeed.net> <1149675056.576658.92120@c74g2000cwc.googlegroups.com> <128dh45bejvrd5d@corp.supernews.com> <1149721730.564878.262550@j55g2000cwa.googlegroups.com> Message-ID: Date: Tue, 13 Jun 2006 03:15:18 GMT Dave wrote: > perfect example. a large scale dry example of colliding dust particles > building an electric field, without need for them hitting a metalic > conductor. dust particles pick up charge by bouncing off each other and the > ground, there can actually be quite a high electric field built up. Is the charge on those dust particles electron based? When cave men rubbed amber on wool to charge it up, was that electrons? One time at a hotel in Odessa, TX, I walked across a wool carpet with leather shoes, went potty, and drew a two inch arc. OUCH! -- 73, Cecil http://www.qsl.net/w5dxp Article: 225227 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <448B2227.2090601@fuse.net> <4H6jg.28755$QP4.3723@fed1read12> Subject: Re: Have any of you mailed this to your ARRL Division directors and SM's yet? Message-ID: Date: Mon, 12 Jun 2006 21:09:51 -0700 "Michael Coslo" wrote in message news:e6jvip$1a4e$1@f04n12.cac.psu.edu... > Sal M. Onella wrote: < snip > > > I learn new tricks every day. Morse Code isn't one of them. > > > The real issue is probably that HF privileges are probably just not that > important to you. < snip > Thanks for explaining it so clearly. That just makes everything right.