Article: 223986 of rec.radio.amateur.antenna From: "Jeff" Subject: Re: Insulation diameter vs Impedance OR how to get 20dBi out of a short Dipole Date: Mon, 1 May 2006 09:10:06 +0100 Message-ID: References: >However, I > found I could reduce the size of a 40M antenna to nearly half by > surrounding the entire radiator with a water jacket only 40cM thick. > It has a good match, and loses roughly a quarter dB to the full size > antenna. It remains to be seen if this is just another aberration, or > is an actual solution. > > 73's > Richard Clark, KB7QHC Surely it is your model that is an aberration. Did it include such things as the loss tangent of the dielectric and the effects of the resistivity of the liquid ? Di-electric loading is a valid concept, but it has to be done sensibly, and modelled even more carefully, taking ALL the effects of the di-electric into account. GIGO. Regards Jeff Article: 223987 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Insulation diameter vs Impedance OR how to get 20dBi out of a Date: Mon, 01 May 2006 02:30:17 -0700 Message-ID: <125bl9gg0e9hu64@corp.supernews.com> References: Jeff wrote: > > Surely it is your model that is an aberration. Did it include such things as > the loss tangent of the dielectric and the effects of the resistivity of the > liquid ? > > Di-electric loading is a valid concept, but it has to be done sensibly, and > modelled even more carefully, taking ALL the effects of the di-electric into > account. GIGO. The flaw is that the "wire insulation" feature of EZNEC is valid only for thin coatings, such as those typically found on insulated wire. I suspect it may also be invalid also for extreme values of dielectric constant. I don't at present know exactly at what thickness or dielectric constant the calculation becomes invalid, so results from models with exceptionally thick and/or high dielectric insulation should be viewed with some skepticism. These limitations aren't spelled out in the EZNEC manual, an oversight on my part for which I apologize. They will be included in the next update to the manual, which will probably be included with the next program update (v. 4.0.27). Roy Lewallen, W7EL Article: 223988 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <1146380239.089435.216750@j33g2000cwa.googlegroups.com> <9731-44552433-56@storefull-3254.bay.webtv.net> <1146481819.035769.4590@y43g2000cwc.googlegroups.com> Subject: Re: Velocity Factor and resonant frequency Message-ID: Date: Mon, 1 May 2006 08:48:11 -0400 There you go again. What applies to you , you are trying to slap on others. Reputation is judged by others, judging our doings and record. How is your statement "JI Engineering" made in public and publications justified? I will not go into listing my accomplishments and professional background like Richard did (it would be another big egg on your pea brain and big mouth), I don't make living of ham radio and I don't care what you think. Fair warning back to you! You starting to sound like Freaktenna, nice going! 73 Yuri wrote in message news:1146481819.035769.4590@y43g2000cwc.googlegroups.com... > Yuri, > > Just a fair warning. > > I'd be very careful what you say in public. > At some point your big mouth and very small brain will get you into > trouble. > > Do not be too bold with your personal comments when you do not know > what you are saying and your statements are full of errors. False > statements if they cause harm will backfire on you, I can promise that. > > On a similar topic, don't blame others for your lack of self-esteem. > When you are and how you feel about yourself isn't anyone's problem but > you own. You make your own reputation Yuri. Please don't try to make > me look as bad as you. > > Tom > Article: 223989 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: Message-ID: Date: Mon, 01 May 2006 13:30:05 GMT Reg Edwards wrote: > For those of you who may be unfamiliar with the mathematics of > transmission lines, download program TWOLINES and enter the following > practical values - > > Line-1 represents the loading coil. > Line-2 represents the whip to be pruned for 1/4-wave resonance. > > Enter Zo1 = 6000 ohms, a practical value. > Enter electrical length L1 = 0.15 wavelengths. > Enter attenuation = 0.1 dB for wire loss in coil. Ignoring losses and starting at 0-j0, plotting this value on a Smith Chart normalized to 6000 ohms, the normalized value is -j1.38 -j1.38 * 6000 = -j8280 ohms > Enter Zo2 = 400 ohms, a practical value. > Enter electrical length L2 = 0.0077 wavelengths. > Enter attenuation = 0.001 dB Starting at 0-j*infinity and plotting backwards, this value on a Smith Chart normalized to 400 ohms is -j20.7 -j20.7 * 400 = -j8280 ohms > But L1 + L2 = 0.1577 wavelengths = only 57 degrees. The abrupt jump from -j1.38 to -j20.7 provides a 66 degree phase shift in the angle of the reflection coefficient as read off the Smith Chart. > The missing 90 - 57 = 33 degrees are just not needed for resonance. > So why is everybody making such a fuss about it? The missing 33 degrees are there, provided by the phase shift in the reflection coefficient. The angle of the reflection coefficient in the stinger at the impedance discontinuity is ~6 degrees. The angle of the reflection coefficient in the coil at the impedance discontinuity is ~72 degrees. 72 - 6 = a 66 degree jump in the angle of the reflection coefficient. That equates to the missing 33 degrees of antenna. The wave that is only 3 degrees back from the tip reflection point is suddenly only 54 degrees from the current maximum point. It appears to me that the interference of the forward and reflected waves at the impedance discontinuity causes an actual 33 degree phase shift. How to analyze what happens at such an impedance discontinuity is covered in my energy analysis article at: http://www.qsl.net/w5dxp/energy.htm I will try to do that analysis sometime today. -- 73, Cecil http://www.qsl.net/w5dxp Article: 223990 of rec.radio.amateur.antenna From: "Richard Fry" References: Subject: Re: A little more on missing degrees Date: Mon, 1 May 2006 08:31:00 -0500 Message-ID: <44560cd1_2@newsfeed.slurp.net> "Reg Edwards" > The missing 90 - 57 = 33 degrees are just not needed for > resonance. So why is everybody making such a fuss about it? _____________ An antenna * system * does not need to have X number of degrees to be resonant. It only needs to have ~zero reactance at its feedpoint -- which, for electrically short AND long radiators can be achieved by use of a suitable matching network. Such networks don't add or subtract electrical degrees, however. They only reduce/cancel the natural reactance of the physical radiator in use. RF Article: 223991 of rec.radio.amateur.antenna From: "Dale Parfitt" References: Subject: Re: Plastic Antenna Insulators Message-ID: <1Vo5g.1304$g01.285@trnddc01> Date: Mon, 01 May 2006 14:27:09 GMT "stargatesg1" wrote in message news:uKb4g.43$Nh7.12@trnddc01... > Anyone ever try using plastic drywall anchors for yagi antenna insulators? > I'm wondering how they will hold up to UV and the weather in general. > > Thanks, > RoD > >Hi Rod, Someone may have already given this response and I missed it. Charles Byers has both insulators and element "keepers" for the insulators. A Google search under this name should turn up the product. Seem to recall they are black delrin. 73, Dale W4OP Article: 223992 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: Velocity Factor and resonant frequency References: <1146380239.089435.216750@j33g2000cwa.googlegroups.com> <9731-44552433-56@storefull-3254.bay.webtv.net> <1146481819.035769.4590@y43g2000cwc.googlegroups.com> Message-ID: Date: Mon, 01 May 2006 15:37:29 GMT Dave wrote: > Yuri and Tom, > > AD Hominem gains nothing except to raise blood pressure and raise > hostility. It certainly does not contribute to the discussion. > > Reasonable people can and do disagree. > > Please, in the interest of Harmony and Respect, let's move on. > > /S/ Deacon Dave (Rev. Mr.), W1MCE > This is one Christian I can agree with. It's hard to see how anyone can get exercised over a coil of wire. 73, Tom Donaly, KA6RUH Article: 223993 of rec.radio.amateur.antenna From: "Dean Craft" References: <44560cd1_2@newsfeed.slurp.net> Subject: Re: A little more on missing degrees Message-ID: Date: Mon, 1 May 2006 11:41:58 -0400 "Richard Fry" wrote in message news:44560cd1_2@newsfeed.slurp.net... > > > An antenna * system * does not need to have X number of degrees to be > resonant. It only needs to have ~zero reactance at its feedpoint -- > which, for electrically short AND long radiators can be achieved by use of > a suitable matching network. > > Such networks don't add or subtract electrical degrees, however. They > only reduce/cancel the natural reactance of the physical radiator in use. > > RF The above post is without doubt, the clearest, cleanest and to the point statement of any made to date in this whole silly chain of posts! It demonstrates a clear and firm grasp of antenna theory. Something that is so obviously missing from 99 percent plus of the bulk of posts on the subject! Dean -- W4IHK Article: 223994 of rec.radio.amateur.antenna From: "Robert Lay (W9DMK)" Subject: Re: spectral power density Date: Mon, 01 May 2006 12:26:29 -0400 Message-ID: References: <1146491265.725531.281770@i39g2000cwa.googlegroups.com> On 1 May 2006 06:47:45 -0700, "electro" wrote: >under unlicensed 2.4GHz FCC part 15 for digital modulation >system(non-spread spectrum), it says that the >1. maximum conducted power is 1W >2. the spectral density be not greater than 8dB for every 3khz band >during continous transmission >3. the 6-dB bandwith is at least 500khz > >question: >1. what is spectral density in this sense and its significance? >2. how can i measure my spectral density? >3. how does 1, 2 and 3 relate to each other? This is just a guess, but let's see what we can do to make some sense out of this. If you were hoping that the 1 watt of power would be evenly distributed across the 3 kHz bandwidth, that would be for the purpose of making sure that no one would be putting all of his 1 watt into a single frequency, which would be quite a strong concentration of power in comparison to having it spread out over the 3 kHz. The idea being that the power when concentrated is very noticeable and might cause QRM, whereas the same wattage spread out evenly over 3 kHz would barely exceed the background noise and would not be noticeable. So, you might want to require that signals not be very "peaky", or concentrated. In order to put limitations on "peakiness", you might require it to be "at least so wide" and "no higher than x" in units of spectral density. Assume that in the above requirement that the 500 Hz bandwidth requirement is to be interpreted as their requirement that avoids the signal being concentrated in a narrow band of frequencies. Also assume that the maximum power density in that 500 Hz bandwidth should be commensurate with the entire 1 watt being distributed over only 500 Hz instead of 3 kHz. Notice how we have traded off the requirements so that they are being applied to 1/6th of the 3 kHz. If we are allowed to concentrate all of our power in 1/6th of the bandwidth, then it follows that we would be required to keep the power density in that bandwidth at no higher than 6X the level it would have when spread out over the entire 3 kHz. I find that it is probably not a coincidence that the 6:1 ratio is almost exactly 8 dB in power ratio. Article: 223995 of rec.radio.amateur.antenna From: Fred Subject: Re: blame the posters not arrl Message-ID: <5jhc52939d5i1334sj0gq88kmsfc8eii1f@4ax.com> References: <1146271643.734737.155940@j73g2000cwa.googlegroups.com> <3lm5521h52e4jgalekjqq6g64e3i59u1mm@4ax.com> <1146333073.590407.297500@i39g2000cwa.googlegroups.com> <1257hrlls8jm694@corp.supernews.com> <33aa52hjph9c5e7bv6a0ihoonjttmsa7q4@4ax.com> <1146434087.455556.152410@u72g2000cwu.googlegroups.com> <13ja521a4t9lajqiiajd47h1siohf5vf8h@4ax.com> <1146449543.853365.112330@j73g2000cwa.googlegroups.com> Date: Mon, 01 May 2006 17:35:10 GMT On 30 Apr 2006 19:12:23 -0700, "an old friend" wrote: > >Fred wrote: >> On 30 Apr 2006 14:54:47 -0700, "an old friend" >? >> > >> >I have a valid license and radio equipment what would I need a waver >> >for? >> >> Hmmm, you tell us. >why? > >you are making the charge you suport >>You certainly don't seem too bright. I am merely >> making an observation of a known quantity. You act like a retard so >> therefore I assume that you are a retard. Die of HIV, loser. > >you just engage in libel and don't post anything on radio I do but you >don't Is it libel or an observation made of your behavior? If you don't want to be thought of as a retard, then learn how to spell and interact with other human beings. Things might change, but for now everyone has a negative perception of you and I am sure we all want you to die from HIV. I am still waiting for a radio post by you. Article: 223996 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> Message-ID: Date: Mon, 01 May 2006 17:47:26 GMT Dean Craft wrote: > The above post is without doubt, the clearest, cleanest and to the point > statement of any made to date in this whole silly chain of posts! It > demonstrates a clear and firm grasp of antenna theory. A self-resonant coil is obviously 90 degrees long. If one removes 5% of the turns and replaces them with a stinger to bring the system back to resonance at the same frequency, do you really believe the coil has magically changed from 90 degrees long to zero degrees long? -- 73, Cecil http://www.qsl.net/w5dxp Article: 223997 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> Message-ID: Date: Mon, 01 May 2006 18:09:57 GMT K7ITM wrote: > But to > invoke "velocity factor" assumes something about the solution which may > well lead you away from the correct explanation. For the feedpoint impedance to be purely resistive, i.e. resonant, for a standing wave antenna, the reflected wave must get back into phase with the forward wave. Velocity factor is a way of explaining how/why that happens. The diameter of the conductor no doubt appears in the VF equation. -- 73, Cecil http://www.qsl.net/w5dxp Article: 223998 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> Message-ID: <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> Date: Mon, 01 May 2006 18:38:53 GMT K7ITM wrote: > Thanks for fulfilling my expectation. EZNEC can be used to verify the relationship of conductor diameter to velocity factor. Once the conductor diameter exceeds a certain limit, the standing wave current at the ends of that conductor undergo a 180 degree phase change, indicating a longer length than resonance. Tom, when you can determine the position and velocity of every electron in the system, please get back to us. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 223999 of rec.radio.amateur.antenna From: Butch Magee Subject: Re: Plastic Antenna Insulators Date: Mon, 01 May 2006 15:00:44 -0500 Message-ID: <125cq81luegl75b@corp.supernews.com> References: stargatesg1 wrote: > Anyone ever try using plastic drywall anchors for yagi antenna insulators? > I'm wondering how they will hold up to UV and the weather in general. > > Thanks, > RoD > > Go to a new home site (under construction) and pick up a few inches of PVC 1/2 in. or 3/4 in. cut them to an appealing size and drill some holes in them at their ends and BAM, insulators! I like mine professional looking so I buy them from Buxcomm.com. They are inexpensive and in several designs or styles and Buck got good prices too!! Butch KF5DE Article: 224000 of rec.radio.amateur.antenna From: "Richard Fry" References: <44560cd1_2@newsfeed.slurp.net> Subject: Re: A little more on missing degrees Date: Mon, 1 May 2006 15:08:54 -0500 Message-ID: <44566a12_1@newsfeed.slurp.net> "Cecil Moore" > A self-resonant coil is obviously 90 degrees long. _____________ A coil is not the electrical equivalent of a linear, physical, ~90-degree, self-resonant radiator. How well do you expect your self-resonant coil to radiate? When you add a stinger to a coil, it is the stinger that radiates the great majority of the applied power. The coil just makes it possible/practical for the tx to supply r-f power to that antenna system that the stinger CAN radiate, by improving the Z match between the source and the feedpoint. RF Article: 224001 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Wire diameter vs Impedance Date: Mon, 01 May 2006 13:45:52 -0700 Message-ID: <125css3of7lppba@corp.supernews.com> References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> Reg Edwards wrote: > > A cylinder has a flat circular end. Antenna wires and rods are > cylinders. You should be reminded that the true length of the antenna > is its straight length PLUS the radius of the flat circular end. > ---- > Reg. What do you mean by "true" length? Roy Lewallen, W7EL Article: 224002 of rec.radio.amateur.antenna From: "Dean Craft" References: <44560cd1_2@newsfeed.slurp.net> Subject: Re: A little more on missing degrees Message-ID: Date: Mon, 1 May 2006 17:11:28 -0400 "Dave" wrote in message news:NoGdnQPKKNlK9svZnZ2dnUVZ_vudnZ2d@comcast.com... > Dean Craft wrote: > > SNIPPED >> >> The above post is without doubt, the clearest, cleanest and to the point >> statement of any made to date in this whole silly chain of posts! It >> demonstrates a clear and firm grasp of antenna theory. Something that is >> so obviously missing from 99 percent plus of the bulk of posts on the >> subject! >> >> Dean -- W4IHK >> >> > > Dean, maybe we can start a discussion about the missing 1% > > "Something that is so obviously missing from 99 percent..." > I have all but given up on that possibility. If its not heated immature school yard rhetoric driven by obvious professional jealousy, then its mind playing games just as has appeared since my earlier post. The troll effect all too frequently takes over and destroys any serious chain of thought. Dean -- W4IHK Article: 224003 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> Subject: Re: Insulation diameter vs Impedance OR how to get 20dBi out of a short Dipole Message-ID: Date: Mon, 1 May 2006 17:24:48 -0400 "Richard Clark" wrote in message news:2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com... > > Further, I do have access to a bulk of work employing water loaded > antennas (peer reviewed and not just more vanity publishing) that can > be used to test reality against theory (as corrupted as it may be by > the aberration factor). > > 73's > Richard Clark, KB7QHC OK, here is the one for the experienced and theoriticians: How about antenna made of wires, submerged just below the surface of water, partially salinated (brakish) or sea water. Would it couple to this huge "water antenna" (variations of insulated vs. bare elements) or connect/tap to it? One experience in this area was, when I operated from VE1ZZ on 160, he has one Eu Beverage that is terminated on the stainless steel hubcap in the ocean. That sucker beats any other "superior" beverages (staggered or phased pairs). Yuri, K3BU Article: 224004 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Wire diameter vs Impedance Date: Mon, 01 May 2006 14:48:38 -0700 Message-ID: <125d0hqiq1jstb3@corp.supernews.com> References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <125css3of7lppba@corp.supernews.com> Reg Edwards wrote: >> What do you mean by "true" length? >> >> > You know very well what I mean. Have you nothing else better to do > with your time? No, I don't know what you mean. And your response doesn't give me a great deal of confidence that you do, either. The reactance of an infinitely thin half wavelength dipole is 42.5 ohms, meaning that it isn't resonant. An infinitely thin dipole of length 0.496 wavelength, or about 1% shorter, is resonant. So my first question is whether the "true length" of an infinitesimally thin resonant dipole is 0.496 or 0.5 wavelength. (If 1% is too little to quibble about, why are we concerned about a length difference of a wire diameter?) If we increase the diameter of the antenna to 1/50 its length, the "true length" would then be 1.02 times the "true length" of the infinitesimally thin dipole. Yet we have to reduce the antenna length by nearly 7% to maintain resonance. So the "true length" doesn't have anything obvious to do with resonant length, nor does it provide a way to predict the resonant length based on wire diameter. If the meaning of "true length" is obvious, most other readers must know what it means. Would someone please be so kind as to explain to me what it means and how it's used? Roy Lewallen, W7EL Article: 224005 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Insulation diameter vs Impedance OR how to get 20dBi out of a Date: Mon, 01 May 2006 15:11:42 -0700 Message-ID: <125d1t27uta90a3@corp.supernews.com> References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> Yuri Blanarovich wrote: > > OK, here is the one for the experienced and theoriticians: > > How about antenna made of wires, submerged just below the surface of water, > partially salinated (brakish) or sea water. Would it couple to this huge > "water antenna" (variations of insulated vs. bare elements) or connect/tap > to it? I don't understand. You're asking about the coupling between a submerged antenna made of wires and a "water antenna"? What's a "water antenna"? How close together are the two antennas? Any submerged antenna would have to be very shallow if it's to receive signals from above the water -- the attenuation of fields traveling through salt water is very high (~16 dB/foot at 1.8 MHz). If it's very deep, it might as well not be there at all. Roy Lewallen, W7EL Article: 224006 of rec.radio.amateur.antenna Date: Mon, 01 May 2006 19:16:13 -0400 From: jawod Subject: Re: blame the posters not arrl References: <1146271643.734737.155940@j73g2000cwa.googlegroups.com> <3lm5521h52e4jgalekjqq6g64e3i59u1mm@4ax.com> <1146333073.590407.297500@i39g2000cwa.googlegroups.com> <1257hrlls8jm694@corp.supernews.com> <33aa52hjph9c5e7bv6a0ihoonjttmsa7q4@4ax.com> <1146434087.455556.152410@u72g2000cwu.googlegroups.com> <13ja521a4t9lajqiiajd47h1siohf5vf8h@4ax.com> <1146449543.853365.112330@j73g2000cwa.googlegroups.com> <5jhc52939d5i1334sj0gq88kmsfc8eii1f@4ax.com> Message-ID: Fred wrote: > On 30 Apr 2006 19:12:23 -0700, "an old friend" > wrote: > > >>Fred wrote: >> >>>On 30 Apr 2006 14:54:47 -0700, "an old friend" >> >>? >> >>>>I have a valid license and radio equipment what would I need a waver >>>>for? >>> >>>Hmmm, you tell us. >> >>why? >> >>you are making the charge you suport >> >>>You certainly don't seem too bright. I am merely >>>making an observation of a known quantity. You act like a retard so >>>therefore I assume that you are a retard. Die of HIV, loser. >> >>you just engage in libel and don't post anything on radio I do but you >>don't > > > Is it libel or an observation made of your behavior? If you don't want > to be thought of as a retard, then learn how to spell and interact > with other human beings. Things might change, but for now everyone has > a negative perception of you and I am sure we all want you to die from > HIV. I am still waiting for a radio post by you. Fred, let it go, man Do YOU have anything related to ham radio to post? Article: 224007 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> <125d1t27uta90a3@corp.supernews.com> Subject: "Ocean as antenna" Message-ID: Date: Mon, 1 May 2006 19:32:20 -0400 Let me change the subject, in order not to interfere with original thread. OK, let me try to elaborate based on what I know and have observed. We know about the effect of distilled water on submerged radiator, it shrinks the dimensions due to dielectric constant. I am not going to distill the Barnegat Bay. We know that salt water or brackish water have high conductivity and act to radio waves as reflector and we can take the advantage of this property by using suitable antenna over or next to it. There is low penetration of such water surface by radio waves, but there should be some RF currents induced close to the surface of said water, (da poor conductor). The question: is there concentration of induced RF currents near the surface, and if so, can we tap them by furnishing proper antenna - transducer? It may be that the whole sandwich of water is just shunted to ground, or is there enough resistance between the ground and surface to allow enough of workable current/signal to collect. The idea is to "gamma match" the giant "water antenna" which is the water surface, in similar fashion as it is done say with aircraft body surface and a slot (antenna). I do not remember this mentioned in the books I have and I wonder if it is possible to harness the ocean as an antenna. Jus' wanted to make sure we do not overlook potential "antenna" at our feet. 73 Yuri, K3BU "Roy Lewallen" wrote in message news:125d1t27uta90a3@corp.supernews.com... > Yuri Blanarovich wrote: >> >> OK, here is the one for the experienced and theoriticians: >> >> How about antenna made of wires, submerged just below the surface of >> water, partially salinated (brakish) or sea water. Would it couple to >> this huge "water antenna" (variations of insulated vs. bare elements) or >> connect/tap to it? > > I don't understand. You're asking about the coupling between a submerged > antenna made of wires and a "water antenna"? What's a "water antenna"? How > close together are the two antennas? > > Any submerged antenna would have to be very shallow if it's to receive > signals from above the water -- the attenuation of fields traveling > through salt water is very high (~16 dB/foot at 1.8 MHz). If it's very > deep, it might as well not be there at all. > > Roy Lewallen, W7EL Article: 224008 of rec.radio.amateur.antenna Subject: Re: blame the posters not arrl From: Steveo Message-ID: <20060501194523.665$XK@newsreader.com> References: <1146271643.734737.155940@j73g2000cwa.googlegroups.com> <3lm5521h52e4jgalekjqq6g64e3i59u1mm@4ax.com> <1146333073.590407.297500@i39g2000cwa.googlegroups.com> <1257hrlls8jm694@corp.supernews.com> <33aa52hjph9c5e7bv6a0ihoonjttmsa7q4@4ax.com> <1146434087.455556.152410@u72g2000cwu.googlegroups.com> <13ja521a4t9lajqiiajd47h1siohf5vf8h@4ax.com> <1146449543.853365.112330@j73g2000cwa.googlegroups.com> <5jhc52939d5i1334sj0gq88kmsfc8eii1f@4ax.com> Date: 01 May 2006 23:29:43 GMT jawod wrote: > Do YOU have anything related to ham radio to post? > Well to be fair it can pertain to any of these groups.. rec.radio.amateur.antenna,rec.radio.amateur.equipment, rec.radio.amateur.policy,rec.radio.cb,rec.radio.shortwave Article: 224009 of rec.radio.amateur.antenna From: Fred Subject: Re: blame the posters not arrl Message-ID: <23cd521iser4stop3dd1q02s8vrhru353u@4ax.com> References: <3lm5521h52e4jgalekjqq6g64e3i59u1mm@4ax.com> <1146333073.590407.297500@i39g2000cwa.googlegroups.com> <1257hrlls8jm694@corp.supernews.com> <33aa52hjph9c5e7bv6a0ihoonjttmsa7q4@4ax.com> <1146434087.455556.152410@u72g2000cwu.googlegroups.com> <13ja521a4t9lajqiiajd47h1siohf5vf8h@4ax.com> <1146449543.853365.112330@j73g2000cwa.googlegroups.com> <5jhc52939d5i1334sj0gq88kmsfc8eii1f@4ax.com> Date: Tue, 02 May 2006 01:07:16 GMT On Mon, 01 May 2006 19:16:13 -0400, jawod wrote: >Fred wrote: >> On 30 Apr 2006 19:12:23 -0700, "an old friend" >> wrote: >> >> >>>Fred wrote: >>> >>>>On 30 Apr 2006 14:54:47 -0700, "an old friend" >>> >>>? >>> >>>>>I have a valid license and radio equipment what would I need a waver >>>>>for? >>>> >>>>Hmmm, you tell us. >>> >>>why? >>> >>>you are making the charge you suport >>> >>>>You certainly don't seem too bright. I am merely >>>>making an observation of a known quantity. You act like a retard so >>>>therefore I assume that you are a retard. Die of HIV, loser. >>> >>>you just engage in libel and don't post anything on radio I do but you >>>don't >> >> >> Is it libel or an observation made of your behavior? If you don't want >> to be thought of as a retard, then learn how to spell and interact >> with other human beings. Things might change, but for now everyone has >> a negative perception of you and I am sure we all want you to die from >> HIV. I am still waiting for a radio post by you. >Fred, let it go, man Since someone sane asked politely. No problem man. I'll be good for now. >Do YOU have anything related to ham radio to post? Maybe, but I am more of a reader than a writer. Article: 224010 of rec.radio.amateur.antenna Subject: Re: blame the posters not arrl From: Steveo Message-ID: <20060501211403.555$Yi@newsreader.com> References: <3lm5521h52e4jgalekjqq6g64e3i59u1mm@4ax.com> <1146333073.590407.297500@i39g2000cwa.googlegroups.com> <1257hrlls8jm694@corp.supernews.com> <33aa52hjph9c5e7bv6a0ihoonjttmsa7q4@4ax.com> <1146434087.455556.152410@u72g2000cwu.googlegroups.com> <13ja521a4t9lajqiiajd47h1siohf5vf8h@4ax.com> <1146449543.853365.112330@j73g2000cwa.googlegroups.com> <5jhc52939d5i1334sj0gq88kmsfc8eii1f@4ax.com> <23cd521iser4stop3dd1q02s8vrhru353u@4ax.com> Date: 02 May 2006 00:58:23 GMT Fred wrote: > Maybe, but I am more of a reader than a writer. > Mee two! Article: 224011 of rec.radio.amateur.antenna From: "Yuri Blanarovich" References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> <125d1t27uta90a3@corp.supernews.com> Subject: Re: "Ocean as antenna" Message-ID: <5rz5g.80$N11.26@fe08.lga> Date: Mon, 1 May 2006 22:26:04 -0400 "Dave" wrote > Sorry for the top post. > > can the premise be restated as follows: > > "Could an insulated wire in a lossy conductive medium [AKA ocean water] > near the surface be modeled as a slot antenna in a lossy plane?" > > + + + and... if there is such an effect what is the best way to "catch the RF waves" grazing the shining ocean surface. More like - can it work besides just being modeled? I have been using "dog loop" antenna, originally RF dog fence around 3/4 acre lot, which is basically wire loop burried about 1 inch below the surface. It has about 600 ohms and works like a goofy Beverage, low noise pickup and still delivering reasonable signal on 80/160. That's why this bugs me, like using floating antenna? Just wondering if there is any potential in this or if anything was written up in the antenna books pro or con. Yuri, K3BU/mm > > Yuri Blanarovich wrote: > >> Let me change the subject, in order not to interfere with original >> thread. >> >> OK, let me try to elaborate based on what I know and have observed. >> >> We know about the effect of distilled water on submerged radiator, it >> shrinks the dimensions due to dielectric constant. I am not going to >> distill the Barnegat Bay. >> >> We know that salt water or brackish water have high conductivity and act >> to radio waves as reflector and we can take the advantage of this >> property by using suitable antenna over or next to it. >> >> There is low penetration of such water surface by radio waves, but there >> should be some RF currents induced close to the surface of said water, >> (da poor conductor). >> >> The question: >> is there concentration of induced RF currents near the surface, and if >> so, can we tap them by furnishing proper antenna - transducer? >> It may be that the whole sandwich of water is just shunted to ground, or >> is there enough resistance between the ground and surface to allow enough >> of workable current/signal to collect. >> The idea is to "gamma match" the giant "water antenna" which is the water >> surface, in similar fashion as it is done say with aircraft body surface >> and a slot (antenna). >> >> I do not remember this mentioned in the books I have and I wonder if it >> is possible to harness the ocean as an antenna. Jus' wanted to make sure >> we do not overlook potential "antenna" at our feet. >> >> 73 Yuri, K3BU >> >> >> >> >> "Roy Lewallen" wrote in message >> news:125d1t27uta90a3@corp.supernews.com... >> >>>Yuri Blanarovich wrote: >>> >>>>OK, here is the one for the experienced and theoriticians: >>>> >>>>How about antenna made of wires, submerged just below the surface of >>>>water, partially salinated (brakish) or sea water. Would it couple to >>>>this huge "water antenna" (variations of insulated vs. bare elements) or >>>>connect/tap to it? >>> >>>I don't understand. You're asking about the coupling between a submerged >>>antenna made of wires and a "water antenna"? What's a "water antenna"? >>>How close together are the two antennas? >>> >>>Any submerged antenna would have to be very shallow if it's to receive >>>signals from above the water -- the attenuation of fields traveling >>>through salt water is very high (~16 dB/foot at 1.8 MHz). If it's very >>>deep, it might as well not be there at all. >>> >>>Roy Lewallen, W7EL >> >> >> > Article: 224012 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: A little more on missing degrees Date: Mon, 1 May 2006 22:59:20 -0500 Message-ID: <20715-4456D918-374@storefull-3255.bay.webtv.net> References: <44560cd1_2@newsfeed.slurp.net> Richard Fry wrote: "Such networks don`t add or subtract electrical degrees, however. They only reduce/cancel the natural reactance of the physical radiator in use." True if the only mismatch is reactance. A too-long antenna can be electrically shortened for matching purposes by tuning it to resonance with the proper series capacitance. A too-short antenna can be electrically lengthened for matching purposes by tuning it to resonance with the proper series inductance. Reactance varies quickly near the resonant length. Radiation resistance varies more slowly tending to increase at a steady rate as the antenna is lengthened. What radiates is current in a length of antenna. What gets current into an antenna is a conjugate match. Reactance is zeroed out, and source and load resistances are matched. That`s what`s needed for maximum power transfer between generator and antenna. Analysis may have been more abundant than needed for practical purposes. The velocity of current through a coil has been disputed. Some said it was almost instantaneous. That was new to me. The nature of inductance is to produce counter emf which by Lenz`s law opposes current into an inductance and temporarily delays current changes in an inductance. Only in a pure resistance is there instantaneous correlation between voltage and current. It is believed that the speed of light "c" is a speed limit on electromagnetic waves. An action in one place must have a delayed response elsewhere depending on distance. I can imagine a wave launched at one of an inductor sweeping across its length and ignoring the round and round path of the wire, but I don`t know of any of the old authors in my collection who say that such a short-cut happens. Conductors are the source of free electrons which permit current flow and my experience is that electricity goes where it is wired. Best regards, Richard Harrison, KB5WZI Article: 224013 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: "Ocean as antenna" Date: Tue, 02 May 2006 02:55:39 -0700 Message-ID: <125eb4vq5mbb030@corp.supernews.com> References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> <125d1t27uta90a3@corp.supernews.com> <5rz5g.80$N11.26@fe08.lga> Yuri Blanarovich wrote: > "Dave" wrote > Sorry for the top post. >> can the premise be restated as follows: >> >> "Could an insulated wire in a lossy conductive medium [AKA ocean water] >> near the surface be modeled as a slot antenna in a lossy plane?" No. To my knowledge, a slot antenna requires a thin plane, which an ocean doesn't resemble. I imagine you could make one in a solid like a chunk of metal, but believe that the hole depth would have to be a substantial fraction of a wavelength. >> >> + + + > > and... > if there is such an effect what is the best way to "catch the RF waves" > grazing the shining ocean surface. More like - can it work besides just > being modeled? Not sure what effect you mean. But NEC-4 models interactions at, above, and below a medium like water with reasonable accuracy. > I have been using "dog loop" antenna, originally RF dog fence around 3/4 > acre lot, which is basically wire loop burried about 1 inch below the > surface. It has about 600 ohms and works like a goofy Beverage, low noise > pickup and still delivering reasonable signal on 80/160. That's why this > bugs me, like using floating antenna? I think you'll find that a buried antenna will work more and more poorly as the ground conductivity gets better and better. As an extreme, how well do you think it would work if buried in an Earth-sized chunk of metal? > Just wondering if there is any potential in this or if anything was written > up in the antenna books pro or con. I think you're on your own. The path is clear for you to be the first to make great discoveries! Just be sure to take a little time off along the way to do make those coil measurements. Roy Lewallen, W7EL Article: 224014 of rec.radio.amateur.antenna From: "amdx" Subject: help with rotor brands Date: Tue, 2 May 2006 05:53:57 -0500 Message-ID: <25d5f$44573a3c$45011502$10993@KNOLOGY.NET> Hi All, I'm searching for a rotor to use with a Flag antenna (as in Flag/Pennant). At present I'm using an Alliance U110 tv antenna rotor. I'm rebuilding my Flag and it will a bit heavier and has lots of leverage, 15ft each side of the mast. The tv rotor seems to have been fine in the past but I need a control unit that is SILENT. The Alliance control unit does the Clunk, Clunk, Clunk as the mast rotates. I don't know any brands or specifications so all info is appreciated. Thanks Mike PS. Is there a group or reflector that might be a better resource for this question? Article: 224015 of rec.radio.amateur.antenna From: gwatts Subject: Re: "Ocean as antenna" References: <2adc521i9itsa47hsbqcp0tnok4ml8c5ov@4ax.com> <125d1t27uta90a3@corp.supernews.com> <5rz5g.80$N11.26@fe08.lga> Message-ID: <01I5g.7626$kg.789@news02.roc.ny> Date: Tue, 02 May 2006 12:26:28 GMT Yuri Blanarovich wrote: ... > and... > if there is such an effect what is the best way to "catch the RF waves" > grazing the shining ocean surface. More like - can it work besides just > being modeled? From http://www.mso.anu.edu.au/cas/presents/don.html I quote "Joe Pawsey took me up to Dover Heights that first day to the cliff-top interferometer. It was a very cunning device. As the sun rose above the ocean there was a reflected ray off the ocean, received by the antenna, and then the direct ray; this formed an interferometer - like a Lloyds mirror type thing - this was the array that found that the Crab Nebula was a radio source, and also did much of the early work on Cygnus" Article: 224016 of rec.radio.amateur.antenna From: John - KD5YI Subject: Re: Wire diameter vs Impedance - correction References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146416277.330091.189340@j73g2000cwa.googlegroups.com> <125a5f49sbulm23@corp.supernews.com> <1146453135.097754.114450@y43g2000cwc.googlegroups.com> <1146453869.698696.76370@j73g2000cwa.googlegroups.com> <1mz5g.10477$t_2.2965@trnddc07> Message-ID: <_JI5g.8915$nV4.6491@trnddc04> Date: Tue, 02 May 2006 13:00:42 GMT Reg Edwards wrote: >>So, if Length / Dia equals e / 4 (about .67957), then C = infinite? >> > > ==================================== > C even goes negative for smaller values of Length/Dia. > > I'll let you into a secret - the formulae are approximate and don't > apply when antenna length is less than about 5 times its diameter. > > When was the last time you saw an antenna wire only 5 times longer > than its diameter? > > You should supply your "secrets" along with your formulae. Article: 224017 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> <44566a12_1@newsfeed.slurp.net> Message-ID: Date: Tue, 02 May 2006 13:52:48 GMT Richard Fry wrote: > "Cecil Moore" >> A self-resonant coil is obviously 90 degrees long. > A coil is not the electrical equivalent of a linear, physical, > ~90-degree, self-resonant radiator. How well do you expect your > self-resonant coil to radiate? Not very well. Nobody is saying that a coil is a good radiator. It probably radiates about as much RF as a piece of wire of the same axial length as the coil. Nothing about the discussion of phase shift through a coil has had anything to do with radiation. In fact, I have ignored radiation from the coil in all of my calculations since I consider it to be negligible. We have a phase shift in a transmission line with negligible radiation. The same is true of a loading coil. > When you add a stinger to a coil, it is the stinger that radiates the > great majority of the applied power. Absolutely no question about that. The round and round design of a coil makes it more akin to a piece of transmission line than it does to a radiator. But like a transmission line stub, it contributes a phase shift to the system. The stub on a properly designed J-Pole doesn't radiate much either. But one can certainly calculate the phase shift from the feedpoint to bottom of the radiating element. Again, the phase shift in the coil has virtually nothing to do with how much the coil radiates. Looking at just one turn on the coil, the current on each side of the turn is approximately equal magnitude and flowing in opposite directions (just as in a transmission line). So virtually all the radiation is canceled by the opposite near fields (just as in a transmission line). -- 73, Cecil http://www.qsl.net/w5dxp Article: 224018 of rec.radio.amateur.antenna From: John - KD5YI Subject: Re: Wire diameter vs Impedance - correction References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146416277.330091.189340@j73g2000cwa.googlegroups.com> <125a5f49sbulm23@corp.supernews.com> <1146453135.097754.114450@y43g2000cwc.googlegroups.com> <1146453869.698696.76370@j73g2000cwa.googlegroups.com> <1mz5g.10477$t_2.2965@trnddc07> <_JI5g.8915$nV4.6491@trnddc04> Message-ID: Date: Tue, 02 May 2006 14:00:47 GMT Reg Edwards wrote: >>You should supply your "secrets" along with your formulae. > > ===================================== > > At my time of life I don't have time to write a book! > > You'll just have to read between the lines. ;o) > ---- > Reg. > > Fine. From now on, I will assume you have no time to explain your "secrets" when you post so I will ignore your formulae. This approach is much better than being misled if I do not read between your lines properly. Article: 224019 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> Message-ID: <93K5g.71838$H71.57495@newssvr13.news.prodigy.com> Date: Tue, 02 May 2006 14:31:33 GMT K7ITM wrote: > Those sources also don't tell me anything about > "velocity factor" as far as I can tell. What RF engineers call "velocity factor" is related to the phase constant in the complex propagation constant embedded in any transmission line equation in any decent textbook. Do your sources tell you anything about the complex propagation constant? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224020 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> <20715-4456D918-374@storefull-3255.bay.webtv.net> Message-ID: Date: Tue, 02 May 2006 14:45:45 GMT Richard Harrison wrote: > I can imagine a wave launched at one of an inductor sweeping across its > length and ignoring the round and round path of the wire, but I don`t > know of any of the old authors in my collection who say that such a > short-cut happens. Conductors are the source of free electrons which > permit current flow and my experience is that electricity goes where it > is wired. Consider a tank circuit link coupled to the outside world. There are probably negligible free electrons flowing from primary to secondary. Yet efficient energy transfer occurs when the coils are tightly coupled. In a loading coil, each turn is tightly coupled to the adjacent turn causing part of the current to be the result of the fields rather than wire path. That's why the VF of the loading coil is roughly double what it would be for "round and round the coil" calculations. The VF for a 75m bugcatcher coil appears to be in the ballpark of 0.04 which is a far cry from the straight across 1.0 or even 0.5 -- 73, Cecil http://www.qsl.net/w5dxp Article: 224021 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> Message-ID: Date: Tue, 02 May 2006 14:55:32 GMT Reg Edwards wrote: > The "end-effect" occurs with any length of antenna. There are only two > ends. Is the lack of an "end-effect" why a full-wave loop has to be made longer than 2*468/f? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224022 of rec.radio.amateur.antenna From: fmmck@aol.com (Fred McKenzie) Subject: Re: Gain of 2.4GHz WiFi vertical Date: Tue, 02 May 2006 12:18:07 -0400 Message-ID: References: <1146576950.559148.53790@j33g2000cwa.googlegroups.com> In article <1146576950.559148.53790@j33g2000cwa.googlegroups.com>, "pdrunen@aol.com" wrote: > Since the antenna is a vertical, I thought that the best low-angle > radiation is 5/8 wave for verticals, anything longer would put the > lobes higher and would result in a lower low angle gain. > > If this is the case then the antenna should only be about 3.5 inches > long. ? PD- The beauty of the 5/8 (0.625) wavelength groundplane antenna, is that its feedpoint impedance has a resistive component of 50 Ohms, and can easily be matched with a small inductor. Some such antennas have been constructed by winding the coil using the base of the antenna rod. It is my recollection from an antennas class 35 years ago, that the best signal towards the horizon comes from a 0.58 wavelength groundplane antenna, not 0.625 wavelength. I can see how 5/8 and 0.58 might be confused, and many may consider the difference trivial. As far as the D-Link antenna, it is most likely a co-axially fed vertical dipole with additional colinear elements separated by phasing networks. Fred Article: 224023 of rec.radio.amateur.antenna From: wood@itd.nrl.navy.mil (J. B. Wood) Subject: Re: Smith Chart inventor Date: Tue, 02 May 2006 12:59:47 -0400 Message-ID: References: <445138e4$0$1007$39cecf19@news.twtelecom.net> In article , "Reg Edwards" wrote: > "Jeff" wrote > > > Smith did not invent the Smith Chart. He simplified, for HF use > only, > > > charts which had been in existence since the Victorian Age, which > > > covered all transmission line frequenies down to telephone and > power > > > frequencies. > > > > > > > That is not quite correct, what Smith did was to take to concept of > the > > pre-existing equations and a rectangular chart which covered a > limited range > > of impedances and develop them into a circular, more complex chart, > that > > covered a full range of impedances. See the Introduction to Smith's > book > > "Electronic Applications of the Smith Chart". > > > > Regards > > Jeff > ========================================= > > Agreed. Your description of what Smith did is more accurate than > mine. > ---- > Reg. Hello, and there appears to be faulty logic here. Any other form of chart not in Smith's format or variants thereof (e.g. a Carter Chart) cannot be a Smith Chart. The fact that Phillip Smith's and similar types of charts are all based upon the transmission line equations is irrelevant to giving due credit to their respective developers. Smith recognizes (pg xv, intro to Smith's book) that similar charts (and their respective limitations) formulated by others inspired him. Do we say that since a couple of brothers from Dayton, Ohio leveraged then-existing aviation technologies and ideas developed by others (e.g. gliders) the Wrights shouldn't be given credit for inventing a successful human carrying, heavier-than-air, propeller-driven aircraft? And for the flip side, while many readily identify Marconi, DeForest, J. Fleming and sometimes Tesla as radio pioneers how many can recall Edwin Armstrong? Sincerely, and 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: 224024 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> Message-ID: Date: Tue, 02 May 2006 17:16:04 GMT Reg Edwards wrote: > Cec, I do wish you would stick to metric dimensions instead of feet > and inches. Sorry, Reg, I'm with the English on that one. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 224025 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <93K5g.71838$H71.57495@newssvr13.news.prodigy.com> Message-ID: Date: Tue, 02 May 2006 17:31:08 GMT Dave wrote: > Complex propagation constant is ? = ? +j? : > ? is the attenuation in Nepers/wavelength > ? is the phase shift in Radians/wavelength > Did I pass ?????????? If I remember correctly, SQRT(Z*Y) results in a dimensionless quantity. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224026 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Gain of 2.4GHz WiFi vertical Date: Tue, 02 May 2006 12:17:29 -0700 Message-ID: <125fc2halekg7d4@corp.supernews.com> References: <1146576950.559148.53790@j33g2000cwa.googlegroups.com> Fred McKenzie wrote: > > The beauty of the 5/8 (0.625) wavelength groundplane antenna, is that its > feedpoint impedance has a resistive component of 50 Ohms, and can easily > be matched with a small inductor. Some such antennas have been > constructed by winding the coil using the base of the antenna rod. It is > my recollection from an antennas class 35 years ago, that the best signal > towards the horizon comes from a 0.58 wavelength groundplane antenna, not > 0.625 wavelength. I can see how 5/8 and 0.58 might be confused, and many > may consider the difference trivial. Maximum gain at the horizon actually occurs at around 0.625 wavelength. At lengths between 0.5 and 0.625, a higher angle lobe appears, but it doesn't divert a significant amount of the total power away from the main lobe until the antenna gets longer than 0.625 wavelength. However, those gain figures are for a vertical antenna mounted on a perfect, infinite, ground plane. Actual performance of 0.5 or 0.625 wavelength antennas compared to quarter wave ones varies a great deal in most typical situations. And any kind of WLAN device I've seen deviates in major ways from the ideal case. Gain of a longer antenna is as likely to be due to placebo effect as to physics. One big advantage of a 0.5 wavelength antenna is its high feedpoint impedance. This makes it much more independent of the other half of the antenna -- what amateurs like to call "ground", but is often the top of a car, a person holding an HT, a router box, etc. The advantage isn't shared by the 0.625 wavelength radiator. Roy Lewallen, W7EL Article: 224027 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: Multi hopping radio waves Date: Tue, 2 May 2006 16:21:49 -0400 Message-ID: <125ffq9kpvg3kd6@corp.supernews.com> References: <19197-4450F612-273@storefull-3257.bay.webtv.net> Dear Group: The use of one number is crude and suitable only if one has imbibed enough grain alcohol or one does not care about Lord K's admonition or both. The preferred scheme is to model the expected virtual heights at each ionospheric reflection (note that the apparent TOA (angles) involved are not likely to be the same at each of these reflections) and then to use the angles involved to note the expected incidence angle of the intermediate "ground" reflection. The coordinates of the expected "ground" reflection areas are calculated and note is taken as to whether those areas are predominately salt-water, ice, or neither. A heuristic algorithm is applied that depends on type of "ground" and that weakly depends on the expected incidence angle. The result is a statistically significant reflection loss. [Some iteration is needed, which computers are very good at doing.] It is important to note that the apparent TOA of the major mode between two points is unlikely to be the same at both ends of the path because the virtual height is unlikely to be the same near both ends. For HF paths greater than something like 12 or 14 Mm predictions become more complex. In all cases of multiple hops (real DX), the TOA at which the gain of the antennas is effective varies between about 12 degrees and 2 degrees. If one wishes a simple predictor, one could find it in a paper published in the UK in the transactions on a conference on HF propagation in the 80s (as I recall) by a BBC engineer (IEE was the publisher). The entire computer code is given in the paper. It uses a simple heuristic model that was found by the BBC to give satisfactory results over the paths that their World Service used. Note that the BBC used paths that did not include much of the polar regions. To digress: The worst path to a DXCC entity from the Upper Midwest is over the magnetic pole to VU4. 100 watt transmitters, ice reflections, heavy absorption, and roughly 10 db more noise at the far end make the need for power and high antennas almost necessary. 73 Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net "Richard Harrison" wrote in message news:19197-4450F612-273@storefull-3257.bay.webtv.net... > > It could be right for some reflections. > > E.A. Laport was Chief Engineer of RCA International when he wrote "Radio > Antenna Engineering". On page 236 Fig. 3.17 shows the effect of ground > conductivity on maximum field strength from a horizontal dipole antenna > versus its height in vavelengths. > > Optimum height would be about 0,50 wavelength to most concentrate energy > at a certain vertical angle, 30-degrees according to the RAF Signal > Manual quoted by Laport. 30-degrees might hop 1000 kilometers. > > At the antenna earth reflection point, frequencies between 2 and 16 MHz > are reduced to 95% of their prereflection field strengths by ordinary > soil from a dipole at 1/2-wavelength height. A reduction to 70.7% of > prereflection strength would represent a 3 dB power loss. So no harm > done yet by the reflection from an antenna over good soil. Lower antenna > height and poorer soil would attenuate more. > > The angle at which rhe signal strikes the earth in subsequent > reflections should be the same as the first reflection from the antenna. > Conductivity and dielectric constant at subsequent earth reflection > points are what they are. > > Shortwave broadcasters use vertically stacked horizontal elements to > concentrate the vertical beam to avoid multipath interference. They also > prefer targets reached on the first reflection from the ionosphere.. > > Best regards, Richard Harrison, KB5WZI > Article: 224028 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Wire diameter vs Impedance Date: Tue, 02 May 2006 15:36:37 -0700 Message-ID: <125fnnqh54t48a7@corp.supernews.com> References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> <1146596054.095856.75500@g10g2000cwb.googlegroups.com> "End effect" looks to me like a description of a result, not an explanation of a cause. Its "proof" consists of the observation that fatter dipoles have a shorter resonant length than thin ones. I'm afraid a real explanation of why the "end effect" occurs requires much deeper physics and math. I don't believe that Tom's result with the top hat is a demonstration of the same phenomenon that makes resonant fat dipoles shorter than thin ones. Here's what the top hat experiment means: Suppose you have a thin antenna of any length. Look at the current distribution on the last few degrees of the antenna. I believe you'll find that it's the same regardless of the antenna length. Then replace the wire with a top hat. Again you'll find that the current distribution on the top hat is the same regardless of the length of the antenna below it. So it shouldn't be surprising that you can substitute one for the other and get the same result regardless of the antenna length. This proves that you can replace a part of an antenna with a capacitive hat, and that the relationship between the length of wire and size of top hat is, at least to first order, independent of the antenna length. It's not clear to me what else it proves. Incidentally, does this have anything to do with the "true length" of an antenna? No one has stepped forward yet with an explanation. Roy Lewallen, W7EL Reg Edwards wrote: > Tom wrote - >> I also used NEC2 to simulate the effects of a small top-hat: it was > 4 >> radial wires at the top of a vertical, 0.001 wavelengths long. The >> vertical diameter was .000001 wavelengths (as were the radials > forming >> the top hat). I found that adding that top had reduced the length > for >> resonance by exactly the same length in each case, for 1/4, 2/4, 3/4 >> and 4/4 wave tall antennas, probably within the accuracy of the >> computing engine. > > ===================================== > > The "End Effect" is thereby proved. > > Marvellous things are computing engines! > ---- > Reg. > > Article: 224029 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> <1146596054.095856.75500@g10g2000cwb.googlegroups.com> <125fnnqh54t48a7@corp.supernews.com> Message-ID: Date: Tue, 02 May 2006 22:52:24 GMT Roy Lewallen wrote: > Suppose you have a thin antenna of any length. Look at the current > distribution on the last few degrees of the antenna. I believe you'll > find that it's the same regardless of the antenna length. For a 1/2WL dipole, it is also the same at the center of the antenna and at all other points anywhere on the antenna. The standing wave current phase cannot be used to measure phase shift in a wire or a coil or a top hat or a stub. The phase of standing wave current is meaningless. If one makes the top hat large enough, one should see an abrupt ~180 phase reversal in the standing wave current. This happens on each side of a current minimum point. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224030 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Multi hopping radio waves Date: Tue, 2 May 2006 20:16:04 -0500 Message-ID: <5950-44580454-606@storefull-3257.bay.webtv.net> References: <125ffq9kpvg3kd6@corp.supernews.com> Mac, N8TT wrote: "Note that the BBC used paths that did not include much of the polar regions." That`s an indication that they knew something about broadcasting. There must be a better way somewhere that doesn`t involve a path near a polar region. A broadcaster must advertise his programs well in advance. He can`t find a band that`s open and tailor his emissions to it. He must fire up on schedule with the right program at the designated time and direction regardless of conditions. All is planned long ahead of time. One of the most usless toys we had was a backscatter ionospheric sounder. It worked well but we had no immediate need for the information it provided. We were locked in our schedules for months in advance and today`s ionospheric conditions were short-term indeed. Best regards, Richard Harrison, KB5WZI Article: 224031 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Multi hopping radio waves Date: Tue, 02 May 2006 18:47:45 -0700 Message-ID: References: <125ffq9kpvg3kd6@corp.supernews.com> <5950-44580454-606@storefull-3257.bay.webtv.net> ORIGINAL MESSAGE: On Tue, 2 May 2006 20:16:04 -0500, richardharrison@webtv.net (Richard Harrison) wrote: >A broadcaster must advertise his programs well in advance. He can`t find >a band that`s open and tailor his emissions to it. He must fire up on >schedule with the right program at the designated time and direction >regardless of conditions. All is planned long ahead of time. *********** REPLY SEPARATOR *********** A good argument for moving international broadcast to the VHF/UHF or higher regions. HF was good when there were no alternatives, but the time has come to retire it. Bill, W6WRT Article: 224032 of rec.radio.amateur.antenna From: Buck Subject: Re: RoomCap Antenna Message-ID: <85vg52t9207ouotls9esq04ple5f3gc584@4ax.com> References: Date: Wed, 03 May 2006 05:49:56 -0400 On Wed, 03 May 2006 03:49:40 GMT, "Don" wrote: >try this one 73 ve7ado > >http://www.eh-antenna.com/library/EH_ANTENNA_FOR_HAMS.pdf > >"Buck" wrote in message >news:jb0a52t70cqcnl4o482hh815fkadf6hbmk@4ax.com... >> Can anyone tell me about this RoomCap Antenna? >> Thanks, Don. -- 73 for now Buck N4PGW Article: 224033 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: 4:1 balun question References: Message-ID: Date: Wed, 03 May 2006 13:16:39 GMT Dan Richardson wrote: > The Sept/Oct 2005 issue of QEX has a 4:1 balun design that may > interest you. It can be found on the ARRL's members only web site. Would a 4:1 voltage balun fed through a husky 1:1 choke (W2DU BALUN) accomplish the same thing? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224034 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: 4:1 balun question References: Message-ID: Date: Wed, 03 May 2006 13:22:45 GMT Mike Coslo wrote: > Do the single core designs really not work? I had a single core > homebrew that seemed to work, but I'm a tad confused after hearing that > they don't. The single core designs are usually voltage baluns and what we hams want are balanced currents. I don't see why you couldn't just add a husky 1:1 W2DU style choke on the 50 ohm side of your 4:1 voltage balun to inhibit common mode current. The extra toroid in the afore mentioned QEX article is a 1:1 choke attached to a 4:1 voltage balun. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224035 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> Message-ID: Date: Wed, 03 May 2006 14:04:39 GMT Dave wrote: > I gave up on the 'missing degrees' and all variations topic about 1 > month ago. Hit the KILL Button and read on! For those who didn't give up, here is a summary of what I was able to do with EZNEC. This exercise should be able to be repeated in the real world. 1. Using the helix feature of EZNEC, I created a 100 turn octagonal coil, 6 inches in diameter, 4 turns per inch. 2. I installed it as a base loading coil over a mininec ground plane and removed turns until it was self-resonant on 4 MHz. That left a total of 69 turns on a 1.435 foot long coil. Give that the coil is 90 degrees at the self- resonant frequency, I calculated a velocity factor of 0.023 for the coil. 3. The coil was then trimmed to half size, i.e. 34.5 turns. Assuming it was then 45 degrees long, the Z0 was determined to be approximately 2200 ohms by looking at the feedpoint impedance reported by EZNEC. 45 degrees from 0-j0 on the Smith Chart is at -j1.0. 4. A stinger was added to the above 45 degrees of coil to bring the antenna back to resonance on 4 MHz. It took 7 ft. of stinger, or 10.2 degrees. 10.2 degrees from 0-j*infinity on the Smith Chart is at -j4.8. 5. The ratio of -j4.8/-j1.0 is the ratio of the Z0 of the coil to the Z0 of the stinger. If the Z0 of the coil is indeed 2200 ohms, the Z0 of the stinger is 458 ohms, just about where it should be. The impedance discontinuity provides the "missing" ~35 degrees of the antenna. 6. Using Dr. Corum's equation for velocity factor yields 0.02 for that coil, a value 13% lower than the one predicted by EZNEC, well within the ballpark for expectations. My conclusions: The delay through a loading coil is in the tens of degrees. The delay through the elements of the antenna do not add up to 90 degrees. In the above EZNEC example, the delay from feedpoint to the tip of the antenna is only 55 degrees. The "missing" degrees are provided by the impedance discontinuity between the coil and the stinger. There is no real- time delay associated with those "missing" degrees. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224036 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <93K5g.71838$H71.57495@newssvr13.news.prodigy.com> Message-ID: Date: Wed, 03 May 2006 14:22:35 GMT Dave wrote: > Alpha and Beta got transformed into ? and j?. Gamma also got transformed > into ?. Now it makes more sense. :-) What is scarey is that some browsers may display Greek characters correctly and some may not. > What kind of bait are you throwing out about SQRT[Z*Y] ? Z is the distributed series impedance and Y is the distributed shunt admittance. The equation for the propagation constant is gamma = alpha + j*beta = SQRT(Z*Y). Doesn't multiplying an impedance by an admittance result in a dimensionless quantity? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224037 of rec.radio.amateur.antenna From: "Robert Lay (W9DMK)" Subject: Re: spectral power density Date: Wed, 03 May 2006 10:32:46 -0400 Message-ID: References: <1146491265.725531.281770@i39g2000cwa.googlegroups.com> <1146496107.299262.109830@i40g2000cwc.googlegroups.com> <1146557393.583471.312740@u72g2000cwu.googlegroups.com> On 2 May 2006 01:09:53 -0700, "electro" wrote: >in other words, when i have a transmit modulation bandwith of 500kbps >my peak power level must be 8 dBm...right? No - that is not correct, in my opinion. My interpretation is that the spectral power density in a 500 Hz bandwidth must not exceed the limit of 2 milliwatts per Hz. (Simply spread the 1 watt over a width of 500 Hz. In my original post I thought your message said 500Hz. Now I see you are saying 500kHz. Which is correct? >what if i use 6khz or >5khz?does proportionality hold here or just say in any bandwith not >greater than 500khz, the peak power level should not always exceed >8dBm?.. The 8 dBm is a red-herring. I took your value of 8 dB as Gospel. If someone says 8 dB they don't mean 8 dBm and vice versa. Can you make sure of the accuracy of your excerpts, because I see nothing in the Part 15 regs that correlate with your numbers. In other words, I'm working with nothing but your excerpts and common sense electrical engineering. Article: 224038 of rec.radio.amateur.antenna From: "Robert Lay (W9DMK)" Subject: Re: A little more on missing degrees Date: Wed, 03 May 2006 10:47:07 -0400 Message-ID: References: <44560cd1_2@newsfeed.slurp.net> <20715-4456D918-374@storefull-3255.bay.webtv.net> On Mon, 1 May 2006 22:59:20 -0500, richardharrison@webtv.net (Richard Harrison) wrote: >Richard Fry wrote: >"Such networks don`t add or subtract electrical degrees, however. They >only reduce/cancel the natural reactance of the physical radiator in >use." > >True if the only mismatch is reactance. A too-long antenna can be >electrically shortened for matching purposes by tuning it to resonance >with the proper series capacitance. A too-short antenna can be >electrically lengthened for matching purposes by tuning it to resonance >with the proper series inductance. > >Reactance varies quickly near the resonant length. Radiation resistance >varies more slowly tending to increase at a steady rate as the antenna >is lengthened. > >What radiates is current in a length of antenna. What gets current into >an antenna is a conjugate match. Reactance is zeroed out, and source and >load resistances are matched. That`s what`s needed for maximum power >transfer between generator and antenna. > >Analysis may have been more abundant than needed for practical purposes. > >The velocity of current through a coil has been disputed. Some said it >was almost instantaneous. That was new to me. The nature of inductance >is to produce counter emf which by Lenz`s law opposes current into an >inductance and temporarily delays current changes in an inductance. Only >in a pure resistance is there instantaneous correlation between voltage >and current. Constraining the discussion to lumped circuit theory, the delay that you speak of would seem to be relevant if one is measuring transient response. However, for a steady-state a.c. current, is it not more appropriate to describe the relationship as a phase lag between the current through and the voltage across the inductor? Further, is it not the case that such phase difference is nominally fixed at near 90 degrees (for a high Q inductor), and is it not true that the velocity is nonetheless at the speed of light? > >It is believed that the speed of light "c" is a speed limit on >electromagnetic waves. An action in one place must have a delayed >response elsewhere depending on distance. > >I can imagine a wave launched at one of an inductor sweeping across its >length and ignoring the round and round path of the wire, but I don`t >know of any of the old authors in my collection who say that such a >short-cut happens. Conductors are the source of free electrons which >permit current flow and my experience is that electricity goes where it >is wired. > >Best regards, Richard Harrison, KB5WZI Article: 224039 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> Message-ID: Date: Wed, 03 May 2006 14:59:21 GMT Dave wrote: > In item 2 you make an unsupported statement: "Give that the coil is 90 > degrees at the self-resonant frequency,..." > > Self resonance only means that the capacitive and inductive reactances, > both distributed, are equal. That does not validate a 90 degree > assumption. Without that validation, IMO, the subsequent discussion is > questionable. Quoting from the Corum paper concerning self resonance of a coil: "The forward and backward traveling waves have superposed to give this voltage standing wave distribution along the resonator. There is a voltage null at the base, a voltage maximum at the top, and a sine wave envelope along the structure." That defines 90 degrees of coil. For the standing wave, there are 90 degrees between a voltage null and a voltage maximum. The voltage maximum at the top of the coil corresponds to the current null existing there because the current has no place to go. The voltage null at the base corresponds to the current maximum there which is a necessary condition for self resonance. There's 90 degrees between a voltage null and a voltage maximum. There's 90 degrees between a current null and a current maximum. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224040 of rec.radio.amateur.antenna From: "Robert Lay (W9DMK)" Subject: Re: spectral power density Date: Wed, 03 May 2006 12:52:15 -0400 Message-ID: <0qnh529sudqlmqmhq5142s58q9ejo4jhse@4ax.com> References: <1146491265.725531.281770@i39g2000cwa.googlegroups.com> On 1 May 2006 06:47:45 -0700, "electro" wrote: >under unlicensed 2.4GHz FCC part 15 for digital modulation >system(non-spread spectrum), it says that the >1. maximum conducted power is 1W >2. the spectral density be not greater than 8dB for every 3khz band >during continous transmission >3. the 6-dB bandwith is at least 500khz > >question: >1. what is spectral density in this sense and its significance? >2. how can i measure my spectral density? >3. how does 1, 2 and 3 relate to each other? I downloaded the FCC's Part 15 regulations and have concluded: 1) They do say 500 kHz bandwidth 2) They do refer to +8dBm - not 8 dB 3) I agree with Tom's response Article: 224041 of rec.radio.amateur.antenna From: Me Subject: Re: Measuring quarter wave cable length with HP 8405A References: <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com> Message-ID: Date: Wed, 03 May 2006 16:52:47 GMT In article <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com>, Gary Schafer wrote: > I am using an HP 8405A vector voltmeter to try and measure the delay > in a transmission line in the 2 meter band. > This is part of a phasing harness for a pair of 2 meter antennas to > put them into circular polarization. > > The set up is as follows: A T connector on the signal generator with a > pair of 75 ohm ¼ wave length jumpers from either side of the T. At the > ends I put an adaptor and a bnc T connector of which one side connects > to the probe of the 8405A and the other end of the bnc T is a 50 ohm > load. > The other 75 ohm ¼ wave jumper has the same setup with the bnc T, 50 > ohm load and B channel probe of the 8405A. > > With this I see a zero degree phase difference on the 8405A as it > should be. > Then I insert a ¼ wave length 50 ohm cable between one of the 75 ohm > cable ends and the bnc T connector / 8405A probe connection point. > There are the same number of adaptors in each side of the lines. The > only addition is one barrel connector and the ¼ wave length of 50 ohm > cable. (this is in the B channel by the way) > The additional barrel connector is part of the ¼ wave length on the 50 > ohm line. > > The wanted frequency is 145 Mhz. > Rather than seeing 90 degrees delay with the added 50 ohm line section > I only see 60 degrees of delay?? If I run the frequency up to around > 180 Mhz I get the 90 degrees delay shown on the 8405A. > What do you suppose I am doing wrong in the measurement setup? > > I have measured the delay on the 50 ohm line section by itself (with > the one barrel connector) and I see 90 degrees of delay at 145 Mhz. I > used 20 db pads on each side of the T from the signal generator to > isolate the two sides of the test setup when measuring this cable by > itself. > > Thanks > Gary K4FMX > When you figured the length of the 1/4 wave section, did you account for the Velocity Factor of the cable? Me Article: 224042 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Measuring quarter wave cable length with HP 8405A References: <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com> Message-ID: Date: Wed, 03 May 2006 17:18:16 GMT Gary Schafer wrote: > The wanted frequency is 145 Mhz. > Rather than seeing 90 degrees delay with the added 50 ohm line section > I only see 60 degrees of delay?? If I run the frequency up to around > 180 Mhz I get the 90 degrees delay shown on the 8405A. > What do you suppose I am doing wrong in the measurement setup? I don't understand the description of the test setup so this may be a stupid question but what would a 50 ohm SWR meter read if installed in that 50 ohm line during the test? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224043 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <93K5g.71838$H71.57495@newssvr13.news.prodigy.com> Message-ID: <7766g.20846$4L1.20063@newssvr11.news.prodigy.com> Date: Wed, 03 May 2006 17:54:11 GMT Dave wrote: > So, the attenuation constant is still a complex number and it is > dimensionless. The attenuation constant is a real number, not a complex number. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224044 of rec.radio.amateur.antenna Date: Wed, 03 May 2006 14:31:12 -0400 From: Dave Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <93K5g.71838$H71.57495@newssvr13.news.prodigy.com> <7766g.20846$4L1.20063@newssvr11.news.prodigy.com> Message-ID: My error ... I meant propagation constant. Cecil Moore wrote: > Dave wrote: > >> So, the attenuation constant is still a complex number and it is >> dimensionless. > > > The attenuation constant is a real number, not a complex number. Article: 224045 of rec.radio.amateur.antenna From: Butch Magee Subject: Re: 4:1 balun question Date: Wed, 03 May 2006 14:00:07 -0500 Message-ID: <125hvhfq0l5vl7f@corp.supernews.com> References: Mike Coslo wrote: > Anyone here have a good web reference on making a 4:1 balun? I'm looking > for the dual core design, not the single core design. Lots of those to > google. > > Do the single core designs really not work? I had a single core > homebrew that seemed to work, but I'm a tad confused after hearing that > they don't. > > - 73 de Mike KB3EIA - > > Better, easier and probably cheaper to buy what you need from Buxcomm.com Article: 224046 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> Message-ID: <4u76g.64848$_S7.5680@newssvr14.news.prodigy.com> Date: Wed, 03 May 2006 19:26:56 GMT Dave wrote: > Where is the other 74 degrees?? Please reference my other postings. It is all explained there. 1. There are tens of degrees in the coil. That phase shift is not instantaneous and obeys the VF of the coil. 2. There are tens of degrees in the impedance discontinuity between the coil and stinger. That phase shift is instantaneous and requires no delay. 3. There are tens of degrees in the stinger. That phase shift is not instantaneous and obeys the VF of the stinger. 4. They all add up to 90 degrees. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224047 of rec.radio.amateur.antenna From: "XaNder" Subject: NewB: antenna and ADC howto Message-ID: <1K76g.18754$TK.18106@tornado.fastwebnet.it> Date: Wed, 3 May 2006 21:43:53 +0200 Hi all, I'm Alexander and I'm a total newbe of radiofrequency comunication. Fortunately I have a little knowledge of physics. Now, my problem is: I want to record a raw UHF signal. First step: I need an antenna. Any suggestion (web HowTos, pdf or anything alike)? Once I have the antenna and the circuitry behind it, I'd need a means of recordingWhen I was at the university we had some nice toys which were able to create (wired) digital signals. No I suppose there also are spectrum analizers which could transform an analogic signal from the antenna to a digital one so it can be easily recorded on a pc. Unfortunately I don't even know how they are called! :-/ I called them ADC (as opposed to DAC), but never heard this term actually. Could you give me a track to follow? Thanks to anyone so kind to help, Alexander Article: 224048 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: A little more on missing degrees Date: Wed, 03 May 2006 13:19:09 -0700 Message-ID: <125i422gjc92dcf@corp.supernews.com> References: <44560cd1_2@newsfeed.slurp.net> Dave wrote: > > Where is the other 74 degrees?? This is the question that started this > 2 month discussion. > > Is there a fallacy in Corum's paper? > > Does Corum's paper apply to a combination of a loading coil and > radiating elements? > > My reasoning is as follows: if I draw a phasor diagram, I have +10 > degrees phase shift from the feed point to the base of the coil. I can > then assume a +90 degree phase shift in the coil, classical inductive > response; then, the 'stinger', from the top of the coil to the tip of > the antenna produces a net -10 degree phase shift from both inductive[+] > and capacitive[-] effects resulting in a net 90 degree phase shift for > the full eight foot antenna. > > Am I being too simplistic? > > I conclude that I have a 16 degree long antenna with a feedpoint > resistance of ~13 ohms [ Rr = ~1.0 ohm and Rloss = ~12 ohms] with zero > ohms reactance [resonant]. [And that the phase shifts stated above are > fundamentally correct.] You don't need to go to anywhere near that much trouble. If you replace the stinger with a lumped series RC to ground with the same impedance as the stinger, you'll get nearly the same currents, both magnitude and phase, at the top and bottom of the coil as you did with the stinger. No "missing degrees" -- no "degrees" at all, in fact. No forward and reverse traveling waves, no standing waves. No smoke and mirrors, no bafflegab. Just plain old circuit analysis. Roy Lewallen, W7EL Article: 224049 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Measuring quarter wave cable length with HP 8405A Date: Wed, 03 May 2006 13:29:59 -0700 Message-ID: <125i4mcgol7vv65@corp.supernews.com> References: <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com> Forgive me for asking questions about seemingly obvious things, but something isn't as it appears. If it's really like you've described, the phase difference should be 90 degrees. Please verify that the added 50 ohm quarter wave section is between the end of the 75 ohm line and the 50 ohm terminator/probe connector as you described and not between the signal generator tee and one of the 75 ohm lines. If the latter, you will get something other than 90 degrees of phase shift, although I haven't run the numbers to see what it would be. Are you sure the added quarter wave line is 50 and not 75 ohms? Also, what's the ratio of voltage magnitudes at the two probes? Roy Lewallen, W7EL Gary Schafer wrote: > I am using an HP 8405A vector voltmeter to try and measure the delay > in a transmission line in the 2 meter band. > This is part of a phasing harness for a pair of 2 meter antennas to > put them into circular polarization. > > The set up is as follows: A T connector on the signal generator with a > pair of 75 ohm ¼ wave length jumpers from either side of the T. At the > ends I put an adaptor and a bnc T connector of which one side connects > to the probe of the 8405A and the other end of the bnc T is a 50 ohm > load. > The other 75 ohm ¼ wave jumper has the same setup with the bnc T, 50 > ohm load and B channel probe of the 8405A. > > With this I see a zero degree phase difference on the 8405A as it > should be. > Then I insert a ¼ wave length 50 ohm cable between one of the 75 ohm > cable ends and the bnc T connector / 8405A probe connection point. > There are the same number of adaptors in each side of the lines. The > only addition is one barrel connector and the ¼ wave length of 50 ohm > cable. (this is in the B channel by the way) > The additional barrel connector is part of the ¼ wave length on the 50 > ohm line. > > The wanted frequency is 145 Mhz. > Rather than seeing 90 degrees delay with the added 50 ohm line section > I only see 60 degrees of delay?? If I run the frequency up to around > 180 Mhz I get the 90 degrees delay shown on the 8405A. > What do you suppose I am doing wrong in the measurement setup? > > I have measured the delay on the 50 ohm line section by itself (with > the one barrel connector) and I see 90 degrees of delay at 145 Mhz. I > used 20 db pads on each side of the T from the signal generator to > isolate the two sides of the test setup when measuring this cable by > itself. > > Thanks > Gary K4FMX > Article: 224050 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: A little more on missing degrees References: <44560cd1_2@newsfeed.slurp.net> <125i422gjc92dcf@corp.supernews.com> Message-ID: Date: Wed, 03 May 2006 22:29:31 GMT Roy Lewallen wrote: > You don't need to go to anywhere near that much trouble. If you replace > the stinger with a lumped series RC to ground with the same impedance as > the stinger, you'll get nearly the same currents, both magnitude and > phase, at the top and bottom of the coil as you did with the stinger. No > "missing degrees" -- no "degrees" at all, in fact. No forward and > reverse traveling waves, no standing waves. No understanding of the laws of physics - just 1001 shortcuts and rules of thumb - consistent with the dumbing down of the US educational system and amateur radio. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224051 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Measuring quarter wave cable length with HP 8405A References: <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com> <125i4mcgol7vv65@corp.supernews.com> <5dai52dp1ftujkssdqjh8398q2l5gusemr@4ax.com> Message-ID: Date: Wed, 03 May 2006 22:34:25 GMT Gary Schafer wrote: > 180 Mhz = -90 degrees A channel -5dbm B channel -2dbm. > 145 Mhz = -60 degrees A channel -3.5dbm B channel -3dbm Did anyone else notice that 90/60 = 75/50? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224052 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Wire diameter vs Impedance Date: Wed, 03 May 2006 15:55:23 -0700 Message-ID: <125id7656rs2vf3@corp.supernews.com> References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> <1146596054.095856.75500@g10g2000cwb.googlegroups.com> <125fnnqh54t48a7@corp.supernews.com> <1146636593.492337.13540@y43g2000cwc.googlegroups.com> Here's an interesting quote from S.A. Schelkunoff, "Theory of Antennas of Arbitrary Size and Shape", Proc. of the I.R.E., September, 1941 (footnote 17): "From the point of view developed in this paper there is no difference between 'end effect' and radiation." This is the paper in which Schelkunoff develops his often-quoted approximate equations for antenna feedpoint impedance (the ones including sine and cosine integral -- Si and Ci -- terms). He says, basically, that an antenna acts like a transmission line -- a conical antenna like a constant-Z line and a cylindrical (e.g., wire or tubing) antenna like a variable-Z line -- *except at the ends*. At the ends, modes other than TEM are excited, resulting in radiation, modification of antenna impedance, and modification of current distribution. The radiation, he says, can be modeled as either a terminating impedance or as a distributed impedance (R and L) along the line. You can find an abbreviated version of this explanation in Kraus' _Antennas_. A transmission line is similar to an antenna in only some respects, and assuming they act exactly the same leads to erroneous conclusions. Among the many mistakes made in recent postings is the assumption that a complete reflection takes place from the end of an antenna wire. As Schelkunoff, Kraus, and others explain, this isn't correct. Roy Lewallen, W7EL Article: 224053 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Wire diameter vs Impedance References: <1146256136.332525.320580@i39g2000cwa.googlegroups.com> <1146504560.509236.51040@j33g2000cwa.googlegroups.com> <1146507445.103318.321540@j73g2000cwa.googlegroups.com> <1Bs5g.392$fb2.83@newssvr27.news.prodigy.net> <1146528536.568289.29120@g10g2000cwb.googlegroups.com> <6eCdnYZlm9BIzMrZnZ2dnUVZ8qudnZ2d@bt.com> <1146596054.095856.75500@g10g2000cwb.googlegroups.com> <125fnnqh54t48a7@corp.supernews.com> <1146636593.492337.13540@y43g2000cwc.googlegroups.com> <125id7656rs2vf3@corp.supernews.com> Message-ID: <5Ia6g.21438$4L1.16339@newssvr11.news.prodigy.com> Date: Wed, 03 May 2006 23:06:41 GMT Roy Lewallen wrote: > A transmission line is similar to an antenna in only some respects, and > assuming they act exactly the same leads to erroneous conclusions. A capacitor and resistor is similar to a stinger in only some respects, and assuming they act exactly the same leads to erroneous conclusions. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224054 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Can you put a ground plane 1/2 wave below the antenna to keep Date: Wed, 03 May 2006 16:11:33 -0700 Message-ID: <125ie59o9r6apa7@corp.supernews.com> References: You would have to create a ground plane that extends many wavelengths >from your antenna. The multiple lobe pattern is produced by reflections >from the ground which are far away -- the lower the angle, the farther >from the antenna. Why don't you just lower the antenna to 1/2 wavelength if that's the pattern you want? Then you'll have just the ground plane you need, the right height below the antenna -- the ground. Roy Lewallen, W7EL Harbin wrote: > Howdy: > When a 1/2 wave vertical is about 1/2 wave off the ground you get > your best radiation pattern without extra lobes, but > if you were to put it on a tower, several wavelengths high, you get > multiple lobes. My question is how can you > keep a clean radiation pattern when you are several wavelengths high > with a 1/2 wave antenna? Can you put a ground > plane 1/2 wave below the antenna to keep the clean pattern? > > -- > SeeYaa:) Harbin Osteen KG6URO Article: 224055 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: measuring impedance - I and V phase, or forward and reflected Date: Wed, 03 May 2006 20:11:30 -0700 Message-ID: <125is77pnh2atd9@corp.supernews.com> References: <-IKdnQYQp4968cTZRVn-iA@comcast.com> dansawyeror wrote: > All, > > What is the best way to base impedance measurements, by voltage and > current phase or by forward and reflected power? Measurement or calculation of forward and reverse power don't give you enough information to determine impedance. There are an infinite number of impedances which result in any given set of forward and reverse powers. Likewise, voltage and current phase don't provide enough information. Again, there are an infinite number of impedances possible for any set of voltage and current phases. > First I assume both methods provide the data to measure impedance. No, neither one does. Among adequate sets of measurements which will allow you to determine impedance are both magnitude and phase of both voltage and current; or the ratio of voltage and current and the difference between their phase angles; or the magnitude and angle of the reflection coefficient. > It would seem that both suffer from the real effects of the taking the > measurement. Measuring voltage suffers from the effects of the reflected > signal, I would assume current does as well. Couplers have a built in > cross talk parameter. It's much more difficult than most people realize to make accurate RF measurements. Any measurements have numerous potential sources of error. If you need accurate results, you should always measure a number of known impedances approximately equal to the measurement being questioned to verify that the system is sound. Measuring antennas brings the additional problems of coupling among the antenna, test equipment, and you; disturbances from other signals being received by the antenna; common mode currents; and properties of connecting feedlines. Roy Lewallen, W7EL Article: 224056 of rec.radio.amateur.antenna From: Buck Subject: Re: Can you put a ground plane 1/2 wave below the antenna to keep the clean pattern? Message-ID: References: Date: Wed, 03 May 2006 23:15:11 -0400 On Wed, 3 May 2006 14:51:05 -0700, "Harbin" wrote: >Howdy: > When a 1/2 wave vertical is about 1/2 wave off the ground you get your best radiation pattern without extra lobes, but >if you were to put it on a tower, several wavelengths high, you get multiple lobes. My question is how can you >keep a clean radiation pattern when you are several wavelengths high with a 1/2 wave antenna? Can you put a ground >plane 1/2 wave below the antenna to keep the clean pattern? create a half-wave dipole and mount it vertically. buck n4pgw -- 73 for now Buck N4PGW Article: 224057 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Measuring quarter wave cable length with HP 8405A Date: Wed, 03 May 2006 20:46:06 -0700 Message-ID: <125iu83jl4b2f3f@corp.supernews.com> References: <3omh52p0s8ch01bocrb8l3bgbd2deg5en9@4ax.com> <125i4mcgol7vv65@corp.supernews.com> <5dai52dp1ftujkssdqjh8398q2l5gusemr@4ax.com> Gary Schafer wrote: > . . . > The length of the 50 ohm line is 9 ¾" from shielded area to shielded > area (not counting the center pin exposed when shell is pulled back). > With the barrel installed it makes it 10 ¾" in length that is > shielded. > . . . By my reckoning, a free space quarter wavelength at 145 MHz is 20.335 inches. Assuming solid polyethylene dielectric coax, this would be about 13.4 inches of coax. 10-3/4 inches would be about 72 degrees. The probes have a shunt C of 2.5 pF, resulting in a Z (-X) of about 440 ohms at 145 MHz, not 100k ohms. If you parallel that with 50 ohms and terminate a 72 degree 50 ohm cable with it, the voltage delay in the cable is 78 degrees -- that is, the imperfect termination actually increases the cable delay by 6 degrees. If the cable Z0 is 45 ohms instead of 50, the delay is a couple of degrees less with that load; if it's 55 ohms, the delay is a couple of degrees more. Maybe your 50 ohm termination isn't quite what you think it is -- as you can see, it doesn't take much to substantially change the cable's delay. As I've said often, most people don't realize how difficult it is to make accurate RF measurements. Roy Lewallen, W7EL Article: 224058 of rec.radio.amateur.antenna From: Allisonnospam@nouce.bellatlantic.net Subject: Re: FCC regulation on max. antenna tower height @ 2.4GHz ??? Message-ID: References: <1146737737.626050.144830@v46g2000cwv.googlegroups.com> Date: Thu, 04 May 2006 12:32:28 GMT On 4 May 2006 03:15:37 -0700, "electro" wrote: >what is the maximum limit for antenna tower @ 2.4ghz ISM band?any link >you know that leads to this regulation? or only the FAA authorizes such >height regulations? > >thanks For towers over 200ft and within a specific distances to an airport there are rules (both FAA and FCC). There may be other restrictions but not specific to only 2.4ghz ISM and local codes are more often an issue than federal codes. Allison Article: 224059 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: measuring impedance - I and V phase, or forward and reflected References: <-IKdnQYQp4968cTZRVn-iA@comcast.com> Message-ID: Date: Thu, 04 May 2006 12:48:28 GMT dansawyeror wrote: > What is the best way to base impedance measurements, by voltage and > current phase or by forward and reflected power? > It would seem that both suffer from the real effects of the taking the > measurement. Measuring voltage suffers from the effects of the reflected > signal, I would assume current does as well. Couplers have a built in > cross talk parameter. If in a transmission line where the Z0 is known, either method will give valid results within a certain accuracy. A bridge circuit would probably yield the most accurate measurement. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224060 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: 4:1 balun question References: Message-ID: Date: Thu, 04 May 2006 13:19:29 GMT Dan Richardson wrote: > Did you read the article Cecil? He place the current balun/choke on > the opposite side. Looked like an interesting approach. Yes, I'm wondering if things would change if the positions were reversed? How does that choke perform when it sees 2000 + j1000 ohms? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224061 of rec.radio.amateur.antenna From: gsm@mendelson.com (Geoffrey S. Mendelson) Subject: Re: FCC regulation on max. antenna tower height @ 2.4GHz ??? Date: Thu, 4 May 2006 13:21:05 +0000 (UTC) Message-ID: References: <1146737737.626050.144830@v46g2000cwv.googlegroups.com> Allisonnospam@nouce.bellatlantic.net wrote: > There may be other restrictions but not specific to only 2.4ghz ISM > and local codes are more often an issue than federal codes. It is also important to check the terms of your license. In the U.S. 2.4gHz is shared between amateur (Ham), ISM (industrial, scientific and medical) and unlicensed users. Each has it's own terms and conditions. For example, the infamous Pringles can antenna was designed and used by an FBI agent in the course of an investigation. It may not have been legal for use by regular unlicensed WiFi users. Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM IL Voice: (07)-7424-1667 IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838 Visit my 'blog at http://geoffstechno.livejournal.com/ Article: 224062 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: May 1st 2006, Civil War Begins References: <1146730693.889876.75440@j73g2000cwa.googlegroups.com> Message-ID: Date: Thu, 04 May 2006 13:51:04 GMT nm5k@wt.net wrote: >>May 1st 2006, Civil War Begins .. > > > LOL, that'll be the day... is this related to "missing degrees" ? > I guess we missed the civil war down here in Texas. May 1 > came and went, and I didn't notice anything irregular at all. > Nothing was hampered, and it is still quite warm here too.. > MK > Nothing happened here in California, either, except that a lot of immigrants had a nice march and got to listen to some inspirational speeches. Afterwords, they all went back to work. 73, Tom Donaly, KA6RUH Article: 224063 of rec.radio.amateur.antenna From: "Cecil Moore" References: Subject: Re: 4:1 balun question Message-ID: Date: Thu, 04 May 2006 15:33:59 GMT "Reg Edwards" wrote: > When it sees 2000 + j1000 ohms there's hardly any current to choke > anyway. Yes, but how much current is there 3/8WL back from that point? -- 73, Cecil, W5DXP Article: 224064 of rec.radio.amateur.antenna From: "Cecil Moore" References: Subject: Re: 4:1 balun question Message-ID: <7eq6g.1670$fb2.1060@newssvr27.news.prodigy.net> Date: Thu, 04 May 2006 16:46:59 GMT "Reg Edwards" wrote: > W5DXP wrote: > > Yes, but how much current is there 3/8WL back from that point? > Isn't that where you should be placing the choke? Kinda hard to do if the feedline is ladder-line. Maybe a more logical thing to do is to increase the length of the ladder-line until a current maximum point is available at the coax/ladder-line junction. -- 73, Cecil, W5DXP Article: 224065 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: measuring impedance - I and V phase, or forward and reflected Date: Thu, 04 May 2006 11:49:37 -0700 Message-ID: <125kj69ov8qqfc4@corp.supernews.com> References: <-IKdnQYQp4968cTZRVn-iA@comcast.com> <125is77pnh2atd9@corp.supernews.com> <4459FB68.2080502@comcast.net> Thanks for the clarification. The HP4805a isn't an impedance meter. It's a vector voltmeter, which measures voltage amplitude and phase. As you know, it requires external directional couplers to measure impedance. (Or you could use current measurements using current probes in addition to the voltage measurements.) When you use directional couplers with the vector voltmeter -- or with a network analyzer for that matter -- you're not measuring forward and reflected power. You're measuring forward and reflected voltage. As I mentioned in my last posting, power measurement doesn't give you enough information to determine impedance. The answer to your question is that you can't measure impedance at all using only the voltage probes of the 4805a, and you can't measure it at all by measuring forward and reverse power with directional couplers. If you want to compare using voltage *and current* probes with measuring forward and reverse *voltages* with directional couplers, the former is probably better when impedances are considerably different than 50 ohms resistive, the latter better in a near 50 ohm system. Making accurate measurements with either method is much more difficult than most people realize, and it helps to have an understanding of what you're actually measuring. Both methods have numerous sources of possible error which have to be understood and controlled. Roy Lewallen, W7EL Network dansawyeror wrote: > Roy, > > Thank you. Yes, I understood both magnitude and phase are required for > both. > > The question arose after looking into the block diagram of an HP 4805a > Impedance Meter. It measures voltage and current as the basis for > determining impedance. > > My work with a vector voltmeter has been through using directional > couplers and measuring forward and reflected power. > > My question is: Is there an inherent accuracy benefit to one measurement > basis over the other? > > Or: Are current and voltage probes inherently easier to build and more > accurate then directional couplers? > > - Dan > > > Roy Lewallen wrote: >> dansawyeror wrote: >> >>> All, >>> >>> What is the best way to base impedance measurements, by voltage and >>> current phase or by forward and reflected power? >> >> >> Measurement or calculation of forward and reverse power don't give you >> enough information to determine impedance. There are an infinite >> number of impedances which result in any given set of forward and >> reverse powers. >> >> Likewise, voltage and current phase don't provide enough information. >> Again, there are an infinite number of impedances possible for any set >> of voltage and current phases. >> >>> First I assume both methods provide the data to measure impedance. >> >> >> No, neither one does. Among adequate sets of measurements which will >> allow you to determine impedance are both magnitude and phase of both >> voltage and current; or the ratio of voltage and current and the >> difference between their phase angles; or the magnitude and angle of >> the reflection coefficient. >> >>> It would seem that both suffer from the real effects of the taking >>> the measurement. Measuring voltage suffers from the effects of the >>> reflected signal, I would assume current does as well. Couplers have >>> a built in cross talk parameter. >> >> >> It's much more difficult than most people realize to make accurate RF >> measurements. Any measurements have numerous potential sources of >> error. If you need accurate results, you should always measure a >> number of known impedances approximately equal to the measurement >> being questioned to verify that the system is sound. Measuring >> antennas brings the additional problems of coupling among the antenna, >> test equipment, and you; disturbances from other signals being >> received by the antenna; common mode currents; and properties of >> connecting feedlines. >> >> Roy Lewallen, W7EL Article: 224066 of rec.radio.amateur.antenna From: Michael Coslo Subject: Re: Plastic Antenna Insulators Date: Thu, 04 May 2006 17:00:46 -0400 Message-ID: References: <8J-dnfyFU-D-w8jZnZ2dnUVZ_tOdnZ2d@adelphia.com> Dave Heil wrote: > Mike Coslo wrote: >> Dave Heil wrote: >>> Highland Ham wrote: >>> ========================= >>> >>>> To be UV resistant the plastic should be black ,eg it contains >>>> carbon black ( like soot) If ,in general, plastic material is >>>> exposed to sun light it deteriorates over time (especially when >>>> pigments are involved). >>>> Example: coloured polypropylene rope . >>>> If that material would be black ,it would have a very long life. >>>> But then the sales of this material would decline ;)), hence you >>>> only find coloured polypropylene rope ,blue ,orange ,red , yellow >>>> ,etc ,at least in the UK. >>>> >>>> Here in the north of Scotland (no sun in abundance) I use >>>> (blue)polypropylene guys on a 13m (40ft)mast ,which have to be >>>> replaced every 7 -8 years .But it is cheap. >>> >>> >>> I question that 7-8 year figure. Some Finnish friends put up a >>> "temporary" tower with a tribander at the OH0Z site in the 1990s. >>> They used new polypropylene ski rope. I went out one weekend and >>> there lay the tower and tribander, victims of a guy rope failure. >>> I'd NEVER use the stuff for guying or antenna supports. >> >> >> I've not found the polyester stuff to be very good either. I >> wonder if that stuff lasting for 7 years might be something else? > > Polyester or polypropylene? The polyester is pretty good even without > the black UV resistant layer. Polypropylene frizzes, fades and gets > weak very, very quickly. > >>>> Polyester rope as used on sailing boats is UV resistant (even >>>> without carbon black) and would last 30+ years ,but it is relatively >>>> expensive. >>> >>> >>> Polyester is excellent material. There is a polyester rope sold >>> under the "Synthetic Textiles" name here in the U.S. which is simply >>> great. >>> It is braided, not twisted. The inner core is white. There is an >>> outer braid which is black. I have some which is fourteen years >>> old. It is still strong and flexible. I've seen it. I might just pt my next antenna up with it. >> Does it have much stretch? I'm looking for something new after >> replacing my dipole the third time since January..... > > One of the very good things about polyester rope is that it doesn't > stretch much at all--let's say, compared to nylon rope which stretches a > great deal. Where I am at, we get some pretty strong and gusty winds the past few years. The trees can get whipping in different directions fairly often. My old nylon string would stretch, and could even support my weight (don't ask how I know that) My thoughts are that iff I put up something that doesn't have a little give, the stress is just going to transfer from the line to the antenna. At that point I'd start breaking the antenna. > Where is your rope breaking and what is it attached to? I use plain old > nylon 1/4" rope to support the end of my inverted L for 160m. The far > end runs though a nylon pulley attached to another rope up in a maple > tree. The rope attached to the antenna runs down the tree and is > attached to an old window sash weight. The weight is free to bob up and > down with the swaying of the tree. That keeps the rope and antenna wire > from breaking. Nothing so complex. I have some line running through a grook in the limbs. The failure point for the old stuff I was using was at the rub point. Now it seems almost random. Your method would probably be a lot better for me to use. >>>> Plastic antenna insulators (sold in the UK ) are usually black , so >>>> are the outdoor balun enclosures and plastic insulators on Yagi >>>> antennes. >>> >>> >>> We're now seeing some white plastic insulators here. I tried some in >>> the sun of Africa. They looked like they were pitted and >>> deteriorating after three years in the sun of Botswana. I either use >>> ceramics or make my own out of 1/2" thick clear plexiglass sheet or >>> 3/4" plexi rod. That yellows but doesn't otherwise seem to deteriorate. >> >> >> I've been using black plastic eggs sold for electric fencing apps. >> They've worked well for about 5 years now. > > They're likely a little short for high power, Mike. You might consider > using a couple of them at each end with a short piece of nylon rope in > between them. I use the black plastic "nail-on" fence insulators for > running a beverage antenna down a tree line. They are cheap and they > work well. The have a snap-in retainer so they're easy to re-use if the > aluminum fence wire I'm using should ever break. > > I use those Hy-Gain center insulators made of black plastic with rubber > membrane and stainless screws and nuts. They never seem to fail and > certainly keep water out of the coaxial cable. Ten-Tec is making their > little Acro-Bat center insulator. It is good for 300 ohm window line > and RG-58 but they don't make a model for RG-213-sized cable. Once again, sounds like a setup I might want to emulate. Thanks, Dave. - 73 de Mike KB3EIA - Article: 224067 of rec.radio.amateur.antenna From: XaNder Subject: Re: NewB: antenna and ADC howto References: <1K76g.18754$TK.18106@tornado.fastwebnet.it> <1146687006.485441.17900@j73g2000cwa.googlegroups.com> Message-ID: Date: Thu, 04 May 2006 23:39:47 +0200 First of all thanks for your answer. K7ITM wrote: > The antenna you pick should depend on just what you are trying to > receive. Could you give us any more info? I have to be able to read an UHF signal produced by an ISO-18000/6 (not B version) RFID reader/tag signal. I first thought to directly use the tag's antenna itself but have no idea of how to connect it to a sampler. Plus it uses backscatter asa means of communication and don't know how this influences any signal at the end of the antenna. > As for digitizing the signal, yes, you can actually buy receivers with > digital output, though good ones tend to be expensive. Well, we are a research lab. Sooner or later I think we'll get our hands on something if it's actually usefull and we ask for it. Nevertheless it has to be as cheap as suitable. --Inline Edit--: I have to ask our providers if they have any passive reader they won't miss ;-) . > If you want > very broadband digitization, you can get ADCs that sample at 10^9 > samples/second and above, but only to about 8 bits of resolution, and > accuracy even less than that. If you want to digitize only a > relatively narrow band, you can use analog techniques to convert the > signal to a lower frequency, or you can use an ADC that is capable of > "undersampling" -- accurately sampling a signal at a frequency above > half its sampling frequency. In either case, you need filters to > insure that the band of frequencies you let through doesn't cause > "aliasing". > (You should be able to find plenty on that with a web search.) Thanks, I'll go and search as I don't remember very well. The band is as narrow as 70MHz if I'm not mistaking. Take a look at http://zone.ni.com/devzone/conceptd.nsf/webmain/1622E8ED427AA28C8625714D0067926D As I told you I'm a total noob and I don't even know if there's only a channel or more (though I think there's only 1) > Anyway, there are some key questions: what signals do you > want to receive, and what bandwidth do you want to digitize? Well, there are lots of RFID protocols out there, but as this is our first test I think we should do simple things. That's why I chose this protocol (it should be simple (yet very complicated for me!) compared to the ISO 18000/6B).Do you think this should be easier in HF (125/130kHz) or VHF (13.56MHz) domain (we have any kind of readers:-). > Do you > want to be able to adjust the center frequency of the band you > digitize, or will it be fixed? What dynamic range do you need? What > amount of noise in the receiver can you tolerate? I'm not really a guru of telecom. The only thing I can say is that the S/N ratio is *probably* no problem to me ... just get the reciever closer to the emitter and I *think* it would be ok. Correct me if I say any nonsense. > Without answers to > these basic questions and some others, you probably won't get the > results you seek. On the back end, another question is, what will you > do with the data? Can you record it or process it real-time without > choking on it? No real-time processing. At least for now and a good deal of time from now. I first have to understand how this works. Plus once it's sampled I can do all the tests I need to. > And finally, are you looking to buy a system, or build > one, or some combination? It depends on how much time would cost (or how much money...). Cheers and thanks again, Alexander From Thu May 4 22:33:03 EDT 2006 Article: 224068 of rec.radio.amateur.antenna NNTP-Posting-Date: Thu, 04 May 2006 19:37:30 -0500 From: Dan Richardson <> Newsgroups: rec.radio.amateur.antenna Subject: Re: J pole question Date: Thu, 04 May 2006 17:37:14 -0700 Message-ID: References: X-Newsreader: Forte Agent 1.93/32.576 English (American) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 23 NNTP-Posting-Host: 68.64.59.124 X-Trace: sv3-WYxW9hVYLWG9wzbiCgCfYK+D2YrRJAQcYmO+jyGYmZAIHCHLnVxGxPRYiHSJ1MmvuuFiGpgiIfWJfnA!gQGtHQTI1M2P9ZRZ4oneFF08UAASxnP/NQnPCCHN6pt7RULKbzpd5YpvY9uG2LpsHQ8Aig7DrI5E!SThHs40LcBi2QPkX5Zmb X-Complaints-To: abuse@adelphia.net X-DMCA-Complaints-To: copyright@adelphia.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.32 Path: news.unc.edu!elk.ncren.net!newsflash.concordia.ca!News.Dal.Ca!ursa-nb00s0.nbnet.nb.ca!nf3.bellglobal.com!border2.nntp.dca.giganews.com!nntp.giganews.com!local01.nntp.dca.giganews.com!nntp.adelphia.com!news.adelphia.com.POSTED!not-for-mail Xref: news0.isis.unc.edu rec.radio.amateur.antenna:224068 On Thu, 4 May 2006 17:20:24 -0700, "Harbin" wrote: >Howdy: > In a j-pole the 1/4 wave element, and the bottom 1/4 of the 3/4 >element should act as a transmission line, right? So... shouldn't these >elements be as very close to each other to cancel one another out, closer >than what I see on most j-poles? Or is this space have something to do >with the impedance of the antenna? Remember you are using wavelengths as your measurement. On 160-meters 6-foot separation would be okay. Danny In my many years I have come to a conclusion that one useless man is a shame, two is a law firm, and three or more is a congress. - John Adams email: k6mhearrlnet http://www.k6mhe.com/ Article: 224069 of rec.radio.amateur.antenna From: "Steve" References: Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Thu, 4 May 2006 18:53:07 -0700 Message-ID: <445ab003$0$65441$742ec2ed@news.sonic.net> Will the CW only portions of the lowbands be retained, or will those go away as well? Steve "Silent Key" wrote in message news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > What's the purpose of ham radio, To have fun talking about rigs and > weather, or to be able to communicate? > > To be able to communicate when no one else can communicate and to advance > radio knowledge & theory? > > What does part 97 say about this? Why does the ARRL ignore it? > > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. > > SC Article: 224070 of rec.radio.amateur.antenna From: Buck Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <5odl52ppqbradod45gk5fa43boanohbffu@4ax.com> References: Date: Thu, 04 May 2006 22:23:51 -0400 On Fri, 05 May 2006 00:15:41 GMT, Silent Key wrote: >What's the purpose of ham radio, To have fun talking about rigs and >weather, or to be able to communicate? > >To be able to communicate when no one else can communicate and to advance >radio knowledge & theory? > >What does part 97 say about this? Why does the ARRL ignore it? > >When CW is lost, new hams will be just like CB'ers and SWL's, or some >other lower life form of radio hobbiest. You name it. > >SC TROLL! CW isn't going away. It just won't be a requirement for a license. RTTY hasn't died either. -- 73 for now Buck N4PGW Article: 224071 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: how many receivers per antenna? Message-ID: Date: Thu, 4 May 2006 20:43:08 -0700 "notyeti" wrote in message news:notyeti.279joh@news.radiobanter.com... > > How can you arrange 16 receivers with an homebrew antenna system? I'd > like to have three antennas or no more than four ideally. I'm not > interested in direction finding, need low profile for neighborhood, and > to work in the space uhf/vhf frequency range. > > Is it really necessary to do much more than hook up the wires, or must > they be electrically isolated somehow and therefore need a fancy > design? > > If it is easier than drawing diagrams, can you otherwise recommend a > low profile space/sat antenna system that might function well with > multiple receivers? Yes, they absolutely must be isolated or you upset the impedance of the system. Isolation is done with splitters or directional coupler taps. T-connectors are often a problem, as they tend to encourage reflections in the cables. I presume that you have a low-noise amp at the antenna that sets the noise figure for the system. Thus, all you have is a divider problem and many, many amplifier/splitters that are flat from 50 - 1000 MHz are available for home and small apartment TV systems. If you need to get into L-band, there are booster amps for SAT-TV that do well from 950-2250 MHz. I googled for 8 way splitter amplifier low noise TV and got this among the thousands: http://www.smarthome.com/7750-8.html not saying it's the best ... it's just one of the many. Good luck. Article: 224072 of rec.radio.amateur.antenna From: John - KD5YI Subject: Re: measuring impedance - I and V phase, or forward and reflected References: <-IKdnQYQp4968cTZRVn-iA@comcast.com> <125is77pnh2atd9@corp.supernews.com> <4459FB68.2080502@comcast.net> <125kj69ov8qqfc4@corp.supernews.com> Message-ID: Date: Fri, 05 May 2006 03:51:52 GMT Wes Stewart wrote: > On Thu, 04 May 2006 11:49:37 -0700, Roy Lewallen > wrote: > > >>Thanks for the clarification. >> >>The HP4805a isn't an impedance meter. It's a vector voltmeter, which >>measures voltage amplitude and phase. As you know, it requires external >>directional couplers to measure impedance. (Or you could use current >>measurements using current probes in addition to the voltage measurements.) > > > Whoa, hold on, wait a minute or as we are now required to say in > Southern Arizona, Alto Amigo! > > I think that Dan made a typo and meant to say "HP-8415", which is a > vector impedance meter that does use a constant current r-f source and > a voltage measurement to determine impedance. > > It's a handy instrument for probing circuits, but it has a limited > higher frequency limit of 108 MHz. > > There is one here: > > http://cgi.ebay.com/HP-4815A-RF-VECTOR-IMPEDANCE-METER-500KHZ-TO-108MHZ_W0QQitemZ7609873605QQcategoryZ25421QQcmdZViewItem > > but without the probe, which makes it totally useless. > > [snip] I think the OP really means 8405 which is a VVM. I think he swapped the first two numbers. He can tell us if I'm wrong. Cheers, John Article: 224073 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <2uA6g.8331$QP4.4556@fed1read12> Date: Thu, 4 May 2006 21:26:37 -0700 "Silent Key" wrote in message news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > What's the purpose of ham radio, To have fun talking about rigs and > weather, or to be able to communicate? > > To be able to communicate when no one else can communicate and to advance > radio knowledge & theory? > > What does part 97 say about this? Why does the ARRL ignore it? > > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. > > SC I should be able to keep this from getting to me, but sometimes I just feel like responding to the attempted intimidation by these elitists. Mate, your key is only silent from the neck, up. Due to dyslexia, I am unable to learn much Morse Code. I can consistently recognize about half of the alphabet and none of the numbers. Morse Code might as well be edoC esroM for all the good it will ever do me. In spite of this, I manage to be a responsible member of the ham radio community and I'm damn proud of my service to RACES, to my club as its treasurer and to the county as a volunteer communicator. My UHF/VHF points in last year's Field Day exceeded the points of our HF stations combined. Lower life form, indeed! The nerve of you! You may get down off your high horse (or should it be "High Morse"?) and apologize for all those jabs any old time it pleases you. I'll be here. Article: 224074 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <1146730693.889876.75440@j73g2000cwa.googlegroups.com> Subject: Re: May 1st 2006, Civil War Begins Message-ID: Date: Thu, 4 May 2006 21:32:36 -0700 "Tom Donaly" wrote in message news:cFn6g.66394$_S7.21780@newssvr14.news.prodigy.com... > nm5k@wt.net wrote: > > >>May 1st 2006, Civil War Begins .. > > > > > > LOL, that'll be the day... is this related to "missing degrees" ? > > I guess we missed the civil war down here in Texas. May 1 > > came and went, and I didn't notice anything irregular at all. > > Nothing was hampered, and it is still quite warm here too.. > > MK > > > > Nothing happened here in California, either, except that a lot > of immigrants had a nice march and got to listen to some inspirational > speeches. Afterwords, they all went back to work. > 73, > Tom Donaly, KA6RUH I got a seat on the train going both ways on Monday -- quite a rarity. They can take the whole month off. Heard a good one on Monday: The illegals telling us to revise our laws is like a burglar telling you to rearrange your furniture. Article: 224075 of rec.radio.amateur.antenna From: "Brenda Ann" Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Fri, 5 May 2006 15:36:46 +0900 Message-ID: References: "Silent Key" wrote in message news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > What's the purpose of ham radio, To have fun talking about rigs and > weather, or to be able to communicate? > > To be able to communicate when no one else can communicate and to advance > radio knowledge & theory? > > What does part 97 say about this? Why does the ARRL ignore it? > > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. > > SC Here's one that I haven't even seen: Not everyone speaks readable English, but anyone that knows Morse can copy any language and read it at their leisure. Also, those who don't speak English well can often spell the words well enough to read... Just a thought. Article: 224076 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: measuring impedance - I and V phase, or forward and reflected Date: Fri, 05 May 2006 02:14:13 -0700 Message-ID: <125m5ra7c46m9d5@corp.supernews.com> References: <-IKdnQYQp4968cTZRVn-iA@comcast.com> <125is77pnh2atd9@corp.supernews.com> <4459FB68.2080502@comcast.net> <125kj69ov8qqfc4@corp.supernews.com> John - KD5YI wrote: > Wes Stewart wrote: >> On Thu, 04 May 2006 11:49:37 -0700, Roy Lewallen >> wrote: >>> . . . >>> The HP4805a isn't an impedance meter. It's a vector voltmeter, which >>> measures voltage amplitude and phase. . . > > I think the OP really means 8405 which is a VVM. I think he swapped the > first two numbers. > > He can tell us if I'm wrong. Can't speak for the OP, but I definitely meant HP8405a, the vector voltmeter. I apologize for the transposition, and also to the OP if I made the wrong assumption about what instrument he meant. Roy Lewallen, W7EL Article: 224077 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: Message-ID: <8wH6g.66656$_S7.2137@newssvr14.news.prodigy.com> Date: Fri, 05 May 2006 12:26:44 GMT Silent Key wrote: > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. CW will not be lost in the same way that AM is not lost. A lot of hams in the 1950's believed that SSB would cause the death of AM and ham radio along with it. SSB operators sounded like Micky Mouse and were known as Single Sidewinders, undesirable snakes in the grass within the hobby, and traitors to the traditional form of amateur radio AM communications. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224078 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: 4:1 balun question References: <1146830635.825068.247610@i39g2000cwa.googlegroups.com> Message-ID: Date: Fri, 05 May 2006 12:32:42 GMT glenn.b.dixon@gmail.com wrote: > I would assume that because the feedline current is common-mode (the > same in both conductors), it will usually travel at the velocity factor > of a wire in air rather than the feedline velocity factor, though I do > not know this. Seems like a reasonable assumption given skin effect and the outside braid of the coax. Common-mode current also, no doubt, forms standing waves with current minimums and maximums 1/4WL apart. A choke would be most effective at a standing wave common mode current maximum point. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224079 of rec.radio.amateur.antenna From: Buck Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: References: <445ab003$0$65441$742ec2ed@news.sonic.net> Date: Fri, 05 May 2006 09:35:12 -0400 On Fri, 05 May 2006 07:08:15 -0400, Dave wrote: >Mis-statements abound again. > >Read the allocation chart in 47 CFR 97.305(a) and 47 CFR 97.305(c). What >CW sub-bands? > >47 CFR 395(a) "An amateur station may transmit a CW emission on ANY >frequency authorized to the control operator." [EMPHASIS ADDED] > >For USA Amateurs CW is authorized as stated above. > >/S/ DD, W1MCE > > Of course, that excludes the new 60 meter frequencies (I dare not call it a 'band'.) -- 73 for now Buck N4PGW Article: 224080 of rec.radio.amateur.antenna From: lsmyer Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: Message-ID: Date: Fri, 05 May 2006 09:50:00 -0400 I know this is a topic that causes the fur to fly, but I'll add my own personal experience. I have wanted a ham license for thirty years. But I have a learning disability that makes it impossible for me to learn a second language. I've tried Spanish, French, and Morse code, and I failed miserably at all three. But even if they eliminated the code, I still wouldn't be able to pass the license test because I am also unable to look at a picture or diagram and convert that visual information into words or ideas. So that pretty much eliminates my ability to read circuit diagrams and process the appropriate information into something usable. I truly admire everyone who has earned their license. Article: 224081 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Fri, 05 May 2006 10:00:23 -0700 Message-ID: References: ORIGINAL MESSAGE: On Fri, 05 May 2006 00:15:41 GMT, Silent Key wrote: >What's the purpose of ham radio, To have fun talking about rigs and >weather, or to be able to communicate? *********** REPLY SEPARATOR *********** 1 2 3 4 5 6 7 8 9 10 / / / / / / / / TROLL-O-METER Bill, W6WRT Article: 224082 of rec.radio.amateur.antenna From: "Steve N." Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Fri, 5 May 2006 11:49:51 -0500 Message-ID: References: Should stay that way... "Silent Key" wrote in message news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > What's the purpose of ham radio, To have fun talking about rigs and > weather, or to be able to communicate? > To be able to communicate when no one else can communicate and to advance > radio knowledge & theory? > What does part 97 say about this? Why does the ARRL ignore it? > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. > SC Well, "SC" a.k.a. troll, Cw, when it came along, was frowned uopn and was predicted to be the death of ham radio as well. Did you know that? Modes currently around that full knowledge of is NOT required to get a licence (where complete knowledge of sending and receiving all the characters in Morse is a requirement): AM, SSB, RTTY, PSK, Paclet, Amtor, APRS, satellite...basically everything else in Amateur Radio! I said *full* knowledge. Do any of the tests require explanations of all five (or is it ten) methods (circuit types and how they function) of generating SSB or how to generate CW...or proper operating practice in all situations? Do you know WHY knowledge of Morse was required in the first place? I think there should be more on the tests on operating practices. I know some Techs who can do much of the above and make better hams that any old fart crying over the supposed loss of CW. I know Extras who couldn't copy code worth a darn, nor do much in the way of tech stuff...so? They're all friends. Your fingers and eyes (or ears) aren't broke... so why aren't you out mentoring new hams? In the last two years, how many programs have you written for helping hams with things like blind hams controlling rigs or or audio tapes on radio operation have you recorded for blind hams or trips to help a blind ham erect an antenna, do a small project or program his radio or cables you've given to a new ham for his antenna or taken a blind ham to a hamfest... Why am *I* wasting my time with this...pfffvt I'll save you the trouble, I'm a 60 year old, 20 WPM Extra and currently spend most of my ham time on 2 & 440 from the car during drive time on repeaters (much more omitted)! I didn't have to learn code in the Navy (though I did happen to already know it) Jerks are everywhere and I wonder why I wasted this time. Guess I just needed a little vent...sorry folks..time for lunch. 73, Steve, K9DCI Answers to the above questions for me: 5, 4,0,1,10,3,1 - not astounding, nor bragging, just true. If you can't Walk the Walk, don't talk garbage. doofus troll... Article: 224083 of rec.radio.amateur.antenna From: "Steve N." Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Fri, 5 May 2006 11:51:28 -0500 Message-ID: References: Sorry for all the cross posting. I didn't look. My bad. (:-( "Steve N." wrote in message news:e3fvnh$97m$1@avnika.corp.mot.com... > Should stay that way... > "Silent Key" wrote in message > news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > > What's the purpose of ham radio, To have fun talking about rigs and > > weather, or to be able to communicate? > > To be able to communicate when no one else can communicate and to advance > > radio knowledge & theory? > > What does part 97 say about this? Why does the ARRL ignore it? > > When CW is lost, new hams will be just like CB'ers and SWL's, or some > > other lower life form of radio hobbiest. You name it. > > SC > > Well, "SC" a.k.a. troll, > > Cw, when it came along, was frowned uopn and was predicted to be the death > of ham radio as well. Did you know that? > > Modes currently around that full knowledge of is NOT required to get a > licence (where complete knowledge of sending and receiving all the > characters in Morse is a requirement): > AM, SSB, RTTY, PSK, Paclet, Amtor, APRS, satellite...basically everything > else in Amateur Radio! > > I said *full* knowledge. Do any of the tests require explanations of all > five (or is it ten) methods (circuit types and how they function) of > generating SSB or how to generate CW...or proper operating practice in all > situations? > > Do you know WHY knowledge of Morse was required in the first place? > > I think there should be more on the tests on operating practices. I know > some Techs who can do much of the above and make better hams that any old > fart crying over the supposed loss of CW. I know Extras who couldn't copy > code worth a darn, nor do much in the way of tech stuff...so? They're all > friends. > > Your fingers and eyes (or ears) aren't broke... so why aren't you out > mentoring new hams? In the last two years, how many programs have you > written for helping hams with things like blind hams controlling rigs or or > audio tapes on radio operation have you recorded for blind hams or trips to > help a blind ham erect an antenna, do a small project or program his radio > or cables you've given to a new ham for his antenna or taken a blind ham to > a hamfest... Why am *I* wasting my time with this...pfffvt > > I'll save you the trouble, I'm a 60 year old, 20 WPM Extra and currently > spend most of my ham time on 2 & 440 from the car during drive time on > repeaters (much more omitted)! > > I didn't have to learn code in the Navy (though I did happen to already know > it) > > Jerks are everywhere and I wonder why I wasted this time. Guess I just > needed a little vent...sorry folks..time for lunch. > 73, Steve, K9DCI > > Answers to the above questions for me: 5, 4,0,1,10,3,1 - not astounding, nor > bragging, just true. > If you can't Walk the Walk, don't talk garbage. > doofus troll... > > From spamtrap_dont_use Sat May 6 18:13:03 EDT 2006 Article: 224084 of rec.radio.amateur.antenna From: Grimly Curmudgeon Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc,rec.radio.amateur.policy,rec.radio.shortwave Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Fri, 05 May 2006 19:01:42 +0100 Organization: Hand-Crafted Abuse From The Emerald Isle Lines: 11 Message-ID: References: Reply-To: projecthoneypot@eircom.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: individual.net FayEIefNnkxeaM6BNso1Rgi0Agh6xAwr0MYOolRtPTIVvk7wU= Cancel-Lock: sha1:Ydw/UuD5QNVOAL8liP8kZeNrbko= X-Newsreader: Forte Agent 1.8/32.548 X-NFilter: 1.2.0 Path: news.unc.edu!elk.ncren.net!usenet.osg.ufl.edu!headwall.stanford.edu!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail Xref: news0.isis.unc.edu rec.radio.amateur.antenna:224084 rec.radio.amateur.equipment:210974 rec.radio.amateur.misc:273711 rec.radio.amateur.policy:258538 rec.radio.shortwave:411638 We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Silent Key saying something like: >When CW is lost, new hams will be just like CB'ers and SWL's, or some >other lower life form of radio hobbiest. You name it. Go back to playing with the dinosaurs. -- Dave Article: 224085 of rec.radio.amateur.antenna From: John Kasupski Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <908n52hq9i6p209o65paqf8ha5sid5dhqf@4ax.com> References: Date: Fri, 05 May 2006 15:01:59 -0400 On Fri, 05 May 2006 19:01:42 +0100, Grimly Curmudgeon wrote: >We were somewhere around Barstow, on the edge of the desert, when the >drugs began to take hold. I remember Silent Key saying >something like: > >>When CW is lost, new hams will be just like CB'ers and SWL's, or some >>other lower life form of radio hobbiest. You name it. > >Go back to playing with the dinosaurs. Best reply of the bunch. Article: 224086 of rec.radio.amateur.antenna Date: Fri, 05 May 2006 16:37:14 -0400 From: Dave Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <445ab003$0$65441$742ec2ed@news.sonic.net> Message-ID: Yep! I stand corrected!! 5330.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. 5346.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. 5366.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. 5371.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. 5403.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. And, "I dare not call it a 'band'" either. Just 5 channels occupied by gentle men and gentle women, both genders, with manners. I have three rigs that operate '60' meters. I've gotten to love that non-band. /S/ DD W1MCE Buck wrote: > On Fri, 05 May 2006 07:08:15 -0400, Dave wrote: > > >>Mis-statements abound again. >> >>Read the allocation chart in 47 CFR 97.305(a) and 47 CFR 97.305(c). What >>CW sub-bands? >> >>47 CFR 395(a) "An amateur station may transmit a CW emission on ANY >>frequency authorized to the control operator." [EMPHASIS ADDED] >> >>For USA Amateurs CW is authorized as stated above. >> >>/S/ DD, W1MCE >> >> > > Of course, that excludes the new 60 meter frequencies (I dare not call > it a 'band'.) > > Article: 224087 of rec.radio.amateur.antenna From: switcher Subject: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! Date: Fri, 05 May 2006 23:53:07 +0200 Message-ID: That's what I did, 10nF added to the loop- var cap setup, and now I see that RMC INfo on 216 comes in with sig 9... (without loop: about 1). Strange thing is that with var cap + 10nF the loop only tunes between say 207 and 225 khz, while on AM (without the 10nF), it tunes 1 MHz wide .. explanation ?? I saw that some people make their own var cap ... (with very large plates...) Now, I intend to buy some nF caps from 1-50nF or so, to see what's happening ... Today I picked up two old grundigs, and after some tweaking (knobs) they work ! melody boy 500 (excellent condition, the AM-FM- etc knobs aren't touched ...) and a Yacht boy with lamp, batt indication, AFC ... tunes very well on SW... Great sound on both radios ... ---and now, for a great song: --- http://www.asklyrics.com/display/Church/Antenna_Lyrics/12119.htm ---- You're just an antenna, you're just a wire. There's a thousand tongues wagging in your ears tonight, And you turn around and you call me a liar. Lightly babe, oh the fine lights cannot find you. She stay out my way, it's the pulse I am aligned to. And everything you say, you'll need that breath one day. Well, you're just an antenna, you're just a code. You translate like a book, the fuses all cook. You eat humble pie and it tastes of the road. Lightly babe, oh the fine lights cannot find you. She say, that's the way, that's the fate I am resigned to. And everything you say, you'll need that breath one day. You're just an antenna, you're just a gauge. You disturb my slumber and round up the numbers And put them inside your velvety cage. Lightly babe, oh the fine lights cannot find you. She say, make my day, and the sunlight will not blind you. Lightly babe, oh the fine lights cannot find you. I may never pray to the fortune that's behind you. -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224088 of rec.radio.amateur.antenna From: switcher Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! References: Date: Sat, 06 May 2006 01:00:54 +0200 Message-ID: http://cgi.ebay.at/RARITAT-GRUNDIG-Weltempfaenger-YACHT-BOY-TOP_W0QQitemZ 7614592587QQcategoryZ19693QQrdZ1QQcmdZViewItem#ebayphotohosting this is the YB I found ... (I don't sell it, yet ... ) -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224089 of rec.radio.amateur.antenna From: David Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! Message-ID: References: Date: Fri, 05 May 2006 23:01:20 GMT On Fri, 05 May 2006 23:53:07 +0200, switcher wrote: >That's what I did, 10nF added to the loop- var cap setup, and now I see >that RMC INfo on 216 comes in with sig 9... (without loop: about 1). > >Strange thing is that with var cap + 10nF the loop only tunes between >say 207 and 225 khz, while on AM (without the 10nF), it tunes 1 MHz wide >.. > >explanation ?? >I saw that some people make their own var cap ... (with very large >plates...) > >Now, I intend to buy some nF caps from 1-50nF or so, to see what's >happening ... > >Today I picked up two old grundigs, and after some tweaking (knobs) they >work ! >melody boy 500 (excellent condition, the AM-FM- etc knobs aren't touched >...) >and a Yacht boy with lamp, batt indication, AFC ... tunes very well on >SW... >Great sound on both radios ... > >---and now, for a great song: --- >http://www.asklyrics.com/display/Church/Antenna_Lyrics/12119.htm >---- >You're just an antenna, you're just a wire. >There's a thousand tongues wagging in your ears tonight, >And you turn around and you call me a liar. >Lightly babe, oh the fine lights cannot find you. >She stay out my way, it's the pulse I am aligned to. >And everything you say, you'll need that breath one day. >Well, you're just an antenna, you're just a code. >You translate like a book, the fuses all cook. >You eat humble pie and it tastes of the road. >Lightly babe, oh the fine lights cannot find you. >She say, that's the way, that's the fate I am resigned to. >And everything you say, you'll need that breath one day. >You're just an antenna, you're just a gauge. >You disturb my slumber and round up the numbers >And put them inside your velvety cage. >Lightly babe, oh the fine lights cannot find you. >She say, make my day, and the sunlight will not blind you. >Lightly babe, oh the fine lights cannot find you. >I may never pray to the fortune that's behind you. written by Roderick Taylor © 1976 Rat's God Music (BMI) Oh what a sunny day When they carried the radio home Bringing him in off of the truck And the dogs wouldn't leave us alone Mr. Radio Come down here to keep us company We listen in a room Through the miles and miles of night Deep in the heart of the Bible Belt In the golden radio light Mr. Radio Come down here to keep us company And it's hard days out in the field The crows in the high tree top If the man's away from his home all day His chickens might fall to the fox Mr. Radio What can you do about that uh huh And you can take me down to a river town Where the citizens dance till dawn Dance so close it's a sin almost The way they carry on Mr. Radio I never dreamed you could And it's miles at the careless touch Of a tired hand in time When evening fell I heard a stranger sell Dreams that were never mine Mr. Radio Come down here to keep us company Come down here to keep us company Article: 224090 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Signal Chaser References: <445ab003$0$65441$742ec2ed@news.sonic.net> Message-ID: Date: Sat, 06 May 2006 00:00:50 GMT "Steve" wrote in news:445ab003$0$65441$742ec2ed@news.sonic.net: > Will the CW only portions of the lowbands be > retained, or will those go away as well? > > Steve I'm fearing it will be Eminent Domain ham radio style. They'll see spectrum that they don't have the ability to use, because there will be no requirement to have that ability. They will want the spectrum for phone. One good thing, there are other modes besides CW that need it, so maybe they won't take our CW portions and give it to phone only hams and appliance operators. SC Article: 224091 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Signal Chaser References: Message-ID: Date: Sat, 06 May 2006 00:00:51 GMT "Brenda Ann" wrote in news:e3ermq$550$1@news2.kornet.net: > > "Silent Key" wrote in message > news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... >> What's the purpose of ham radio, To have fun talking about rigs and >> weather, or to be able to communicate? >> >> To be able to communicate when no one else can communicate and to >> advance radio knowledge & theory? >> >> What does part 97 say about this? Why does the ARRL ignore it? >> >> When CW is lost, new hams will be just like CB'ers and SWL's, or some >> other lower life form of radio hobbiest. You name it. >> >> SC > > Here's one that I haven't even seen: > > Not everyone speaks readable English, but anyone that knows Morse can > copy any language and read it at their leisure. Also, those who don't > speak English well can often spell the words well enough to read... > > Just a thought. Thank you. In a way, it's sort of like sign-language. Two people that don't know each others tongue but know sign language can still communicate. SC Article: 224092 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Signal Chaser References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> Message-ID: Date: Sat, 06 May 2006 00:00:54 GMT "John S." wrote in news:1146827830.022860.277130@j73g2000cwa.googlegroups.com: > Silent Key wrote: >> What's the purpose of ham radio, To have fun talking about rigs and >> weather, or to be able to communicate? >> >> To be able to communicate when no one else can communicate and to >> advance radio knowledge & theory? >> >> What does part 97 say about this? Why does the ARRL ignore it? >> >> When CW is lost, new hams will be just like CB'ers and SWL's, or some >> other lower life form of radio hobbiest. You name it. > > > If you really believe that morse code is an important way to > communicate that should be preserved then you need to convince other > hams and potential hams to learn the code. You need to convince enough > hams to use code so its very usage generates excitement and makes > people want to join in the fun. Almost self-perpetuating like it was > in the 1950's. > > Preaching (or complaining) to the choir on the radio fora about the > abysmal state of things will not add one person to the ranks of key > pounding hams. > > So what are you going to do to increase the number of code practicing > hams. Call the FCC, email the ARRL. Tell them you don't want to see ham radio dumbed down anymore, for the good of the service and the good of country. God bless America. Amen SC Article: 224093 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Signal Chaser References: Message-ID: <%GR6g.4157$Vn.1486@newsread4.news.pas.earthlink.net> Date: Sat, 06 May 2006 00:00:59 GMT Bill Turner wrote in news:d41n521h7vkt7e7isn0lafj1hmojka7m6l@4ax.com: > ORIGINAL MESSAGE: > > On Fri, 05 May 2006 00:15:41 GMT, Silent Key wrote: > > >>What's the purpose of ham radio, To have fun talking about rigs and >>weather, or to be able to communicate? > > *********** REPLY SEPARATOR *********** > > 1 2 3 4 5 6 7 8 9 10 > / > / > / > / > / > / > / > / > TROLL-O-METER > > > Bill, W6WRT Come on Bill, I know you care more about ham radio than to just post the meter. SC Article: 224094 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Silent Keys References: <2uA6g.8331$QP4.4556@fed1read12> Message-ID: Date: Sat, 06 May 2006 00:00:57 GMT "Sal M. Onella" wrote in news:2uA6g.8331$QP4.4556@fed1read12: > > "Silent Key" wrote in message > news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... >> What's the purpose of ham radio, To have fun talking about rigs and >> weather, or to be able to communicate? >> >> To be able to communicate when no one else can communicate and to >> advance radio knowledge & theory? >> >> What does part 97 say about this? Why does the ARRL ignore it? >> >> When CW is lost, new hams will be just like CB'ers and SWL's, or some >> other lower life form of radio hobbiest. You name it. >> >> SC > > I should be able to keep this from getting to me, but sometimes I just > feel like responding to the attempted intimidation by these elitists. > > Mate, your key is only silent from the neck, up. > > Due to dyslexia, I am unable to learn much Morse Code. I can > consistently recognize about half of the alphabet and none of the > numbers. Morse Code might as well be edoC esroM for all the good it > will ever do me. > > In spite of this, I manage to be a responsible member of the ham radio > community and I'm damn proud of my service to RACES, to my club as its > treasurer and to the county as a volunteer communicator. My UHF/VHF > points in last year's Field Day exceeded the points of our HF stations > combined. Lower life form, indeed! The nerve of you! Yes, but can you send and receive Code at 13 or 20wpm? What if in an emergency your microphone broke, and the only thing you had to save a life was CW? With your skills, that person would die. In that situation you'd be about as useful as two tin cans and a piece of string. SC Article: 224095 of rec.radio.amateur.antenna Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. From: Save Cw References: Message-ID: <1HR6g.4158$Vn.3109@newsread4.news.pas.earthlink.net> Date: Sat, 06 May 2006 00:01:01 GMT "Steve N." wrote in news:e3fvnh$97m$1@avnika.corp.mot.com: > Should stay that way... > "Silent Key" wrote in message > news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... >> What's the purpose of ham radio, To have fun talking about rigs and >> weather, or to be able to communicate? >> To be able to communicate when no one else can communicate and to >> advance radio knowledge & theory? >> What does part 97 say about this? Why does the ARRL ignore it? >> When CW is lost, new hams will be just like CB'ers and SWL's, or some >> other lower life form of radio hobbiest. You name it. >> SC > > Well, "SC" a.k.a. troll, > > Cw, when it came along, was frowned uopn and was predicted to be the > death of ham radio as well. Did you know that? > > Modes currently around that full knowledge of is NOT required to get a > licence (where complete knowledge of sending and receiving all the > characters in Morse is a requirement): > AM, SSB, RTTY, PSK, Paclet, Amtor, APRS, satellite...basically > everything else in Amateur Radio! > > I said *full* knowledge. Do any of the tests require explanations of > all five (or is it ten) methods (circuit types and how they function) of > generating SSB or how to generate CW...or proper operating practice in > all situations? > > Do you know WHY knowledge of Morse was required in the first place? > > I think there should be more on the tests on operating practices. I > know some Techs who can do much of the above and make better hams that > any old fart crying over the supposed loss of CW. I know Extras who > couldn't copy code worth a darn, nor do much in the way of tech > stuff...so? They're all friends. > > Your fingers and eyes (or ears) aren't broke... so why aren't you out > mentoring new hams? In the last two years, how many programs have you > written for helping hams with things like blind hams controlling rigs or > or audio tapes on radio operation have you recorded for blind hams or > trips to help a blind ham erect an antenna, do a small project or > program his radio or cables you've given to a new ham for his antenna or > taken a blind ham to a hamfest... Why am *I* wasting my time with > this...pfffvt > > I'll save you the trouble, I'm a 60 year old, 20 WPM Extra and currently > spend most of my ham time on 2 & 440 from the car during drive time on > repeaters (much more omitted)! > > I didn't have to learn code in the Navy (though I did happen to already > know it) > > Jerks are everywhere and I wonder why I wasted this time. Guess I just > needed a little vent...sorry folks..time for lunch. > 73, Steve, K9DCI > > Answers to the above questions for me: 5, 4,0,1,10,3,1 - not astounding, > nor bragging, just true. > If you can't Walk the Walk, don't talk garbage. > doofus troll... Right, that's the service nature of hams. Hams helping hams, and hams serving the community. And Dumbing it down can effect the quality of service. Maybe it won't go totally to shit while you and I are still around, but it will happen. In Life, What happens when standards are lowered, things get better? SC From spamtrap_dont_use Sat May 6 18:13:04 EDT 2006 Article: 224096 of rec.radio.amateur.antenna From: Grimly Curmudgeon Newsgroups: rec.radio.amateur.antenna,rec.radio.amateur.equipment,rec.radio.amateur.misc,rec.radio.amateur.policy,rec.radio.shortwave Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Sat, 06 May 2006 01:22:57 +0100 Organization: Hand-Crafted Abuse From The Emerald Isle Lines: 24 Message-ID: References: <2HR6g.4159$Vn.2910@newsread4.news.pas.earthlink.net> Reply-To: projecthoneypot@eircom.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: individual.net zvacYdY1iL5AbQu5BHUcaw5oI5HiZ3eFwJ0Vawtv+FacoLbpE= Cancel-Lock: sha1:2uqmQHZKK/XbGcbw82Q1G0FOKz0= X-Newsreader: Forte Agent 1.8/32.548 X-NFilter: 1.2.0 Path: news.unc.edu!elk.ncren.net!news2.wam.umd.edu!bloom-beacon.mit.edu!npeer.de.kpn-eurorings.net!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail Xref: news0.isis.unc.edu rec.radio.amateur.antenna:224096 rec.radio.amateur.equipment:210983 rec.radio.amateur.misc:273732 rec.radio.amateur.policy:258562 rec.radio.shortwave:411661 We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Signal Chaser saying something like: >Grimly Curmudgeon wrote in >news:qn4n52h2mfhjb33l632pt47qcqtb5vfh5a@4ax.com: > >> We were somewhere around Barstow, on the edge of the desert, when the >> drugs began to take hold. I remember Silent Key saying >> something like: >> >>>When CW is lost, new hams will be just like CB'ers and SWL's, or some >>>other lower life form of radio hobbiest. You name it. >> >> Go back to playing with the dinosaurs. > > >Sorry, Didn't copy. Send it to me in CW. --. --- / -... .- -.-. -.- / - --- / .--. .-.. .- -.-- .. -. --. / .-- .. - .... / - .... . / -.. .. -. --- ... .- ..- .-. ... -- Dave Article: 224097 of rec.radio.amateur.antenna Message-ID: <445BF67E.CA5D836F@earthlink.net> From: "Michael A. Terrell" Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW References: Date: Sat, 06 May 2006 01:07:10 GMT K7ITM wrote: > > I think he means to buy some fixed caps in the range 1-50nF, not a > 1-50nF variable. (Though in this forum, maybe he does mean the > variable!) The fixed caps could make some sense. Maybe put them on > dual stackable banana plugs, and plug together whatever value is > desired. You could use a solid state analog mux IC to switch capacitors at those frequencies. Maxim, Analog Devices and others make a wide selection of these chips. -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida Article: 224098 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: Message-ID: Date: Sat, 06 May 2006 02:11:52 GMT Signal Chaser wrote: > "Brenda Ann" wrote in >>Not everyone speaks readable English, but anyone that knows Morse can >>copy any language and read it at their leisure. Also, those who don't >>speak English well can often spell the words well enough to read... >> > In a way, it's sort of like sign-language. Two people that don't know > each others tongue but know sign language can still communicate. Of course, the same thing is possible on SSB communicating phonetically. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224099 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> Message-ID: Date: Sat, 06 May 2006 02:13:03 GMT Signal Chaser wrote: > Call the FCC, email the ARRL. Tell them you don't want to see ham radio > dumbed down anymore, for the good of the service and the good of country. Let's require a EE degree instead of Morse Code. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224100 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <2uA6g.8331$QP4.4556@fed1read12> Message-ID: Date: Sat, 06 May 2006 02:14:59 GMT Silent Keys wrote: > What if in an emergency your microphone broke, and the only thing you had > to save a life was CW? What if the aliens invaded and all they couldn't understand was CW? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224101 of rec.radio.amateur.antenna Date: Fri, 05 May 2006 22:35:02 -0500 From: Tom Ring Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <445ab003$0$65441$742ec2ed@news.sonic.net> Message-ID: <445c1967$0$6152$39cecf19@news.twtelecom.net> Signal Chaser wrote: > I'm fearing it will be Eminent Domain ham radio style. > > They'll see spectrum that they don't have the ability to use, because > there will be no requirement to have that ability. They will want the > spectrum for phone. One good thing, there are other modes besides CW that > need it, so maybe they won't take our CW portions and give it to phone > only hams and appliance operators. > > SC Well, with the 4 or 5 CW signals that are on most bands at any given time (except VHF and up during contests, BTW), who would notice the loss. No offense, but if CW ops want to keep the territory, they'd better start populating it. tom K0TAR Article: 224102 of rec.radio.amateur.antenna Date: Fri, 05 May 2006 22:43:05 -0500 From: Tom Ring Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> Message-ID: <445c1b4a$0$6152$39cecf19@news.twtelecom.net> Signal Chaser wrote: >>Preaching (or complaining) to the choir on the radio fora about the >>abysmal state of things will not add one person to the ranks of key >>pounding hams. >> >>So what are you going to do to increase the number of code practicing >>hams. > > > > Call the FCC, email the ARRL. Tell them you don't want to see ham radio > dumbed down anymore, for the good of the service and the good of country. > > God bless America. Amen > > SC > Yup, that increased the number of CW ops by a lot. Typical old style ham response. Moron. Pure and simple moron. This is why CW is losing the battle. Not because it's a lost art, or something that's not worthwhile, but because the "supporters" do nothing but complain. I don't want to see CW go away; I think it's a "good thing", and should stay around, especially for things it still does well, such as EME. Of course this is not the place to speak of "advanced" things like EME, after all, it's only been around for 50 years. tom K0TAR Article: 224103 of rec.radio.amateur.antenna From: Buck Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <887o52psg5m4r5hrn4hjpc9s8c8sb8cqgh@4ax.com> References: <445ab003$0$65441$742ec2ed@news.sonic.net> Date: Fri, 05 May 2006 23:53:28 -0400 On Fri, 05 May 2006 16:37:14 -0400, Dave wrote: >Yep! I stand corrected!! >5330.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. >5346.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. >5366.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. >5371.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. >5403.5 KHz USB ONLY, Maximum band width 2.8 KHz. 50 watts ERPd max. > >And, "I dare not call it a 'band'" either. Just 5 channels occupied by >gentle men and gentle women, both genders, with manners. > >I have three rigs that operate '60' meters. I've gotten to love that >non-band. > >/S/ DD W1MCE > >Buck wrote: > I love it too. It's a great mobile band, but I don't have a mobile antenna for it. I have used it with a tuned dipole a good bit. Even talked to England once. It is mostly stateside comms, but its like you said, a lot of gentlemen and gentlewomen! I am hoping to get an antenna for it in the near future for both the car and my new location. 73 for now. PS there is a sixth channel only available in and around Alaska, but I forget the frequency. It is an emergency only channel. -- 73 for now Buck N4PGW Article: 224104 of rec.radio.amateur.antenna From: Buck Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <1f7o52hs7g8ee1u0kg6013bo0po968s5ol@4ax.com> References: <445ab003$0$65441$742ec2ed@news.sonic.net> Date: Fri, 05 May 2006 23:55:19 -0400 On Thu, 4 May 2006 18:53:07 -0700, "Steve" wrote: >Will the CW only portions of the lowbands be >retained, or will those go away as well? > > Steve > There are no 'cw only' portions. They are 'digital' portions. -- 73 for now Buck N4PGW Article: 224105 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 00:09:19 -0500 From: Tom Ring Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <2uA6g.8331$QP4.4556@fed1read12> Message-ID: <445c2f80$0$1005$39cecf19@news.twtelecom.net> Cecil Moore wrote: > Silent Keys wrote: > >> What if in an emergency your microphone broke, and the only thing you had >> to save a life was CW? > > > What if the aliens invaded and all they couldn't understand > was CW? Which is most likely, actually. We broadcast a lot more voice than CW, Ever noticed how many watts of television, FM radio and AM radio are out there versus CW? CW is effectivly dead except for those that wish to keep it alive. Similar to the old car collectors. Nothing wrong with it. beautiful collector items, but not really part of the current world. Article: 224106 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 00:20:56 -0500 From: Tom Ring Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> <445c1b4a$0$6152$39cecf19@news.twtelecom.net> Message-ID: <445c3238$0$6144$39cecf19@news.twtelecom.net> Tom Ring wrote: > I don't want to see CW go away; I think it's a "good thing", and should > stay around, especially for things it still does well, such as EME. Of > course this is not the place to speak of "advanced" things like EME, > after all, it's only been around for 50 years. > > tom > K0TAR Bet no one from the antenna newsgroup even bothers to respond with anything worthwhile. This is, after all, a group of people that thinks the world ends at 10 meters. (Except for a very very few, and you know I'm not speaking of you). tom K0TAR Article: 224107 of rec.radio.amateur.antenna From: switcher Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! References: <1146876510.667640.212510@j33g2000cwa.googlegroups.com> Date: Sat, 06 May 2006 08:35:28 +0200 Message-ID: In article <1146876510.667640.212510@j33g2000cwa.googlegroups.com>, "K7ITM" wrote: > I think he means to buy some fixed caps in the range 1-50nF, not a > 1-50nF variable. Yes, I would buy fixed, of course, they have them in eu at www.conrad.fr / .de /.be / .nl -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224108 of rec.radio.amateur.antenna From: switcher Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! References: Date: Sat, 06 May 2006 09:16:34 +0200 Message-ID: In article , switcher wrote: > That's what I did, 10nF added to the loop- var cap setup, and now I see > that RMC INfo on 216 comes in with sig 9... (without loop: about 1). > > Strange thing is that with var cap + 10nF the loop only tunes between > say 207 and 225 khz, while on AM (without the 10nF), it tunes 1 MHz wide > .. Of course, now I can add more turns to the loop. The loop is 2 x 3 meter of PVC tube, bended in a circle. There are now 3 turns. Guess ... how many turns to have the LW 153-279khz ??? picture of a previous version , large (2 m) and small 83 cm hulahoop http://users.fulladsl.be/spb13810/oc/IMAG0015.JPG The way I construct the hulahoop now, so that it "keeps head up": http://users.fulladsl.be/spb13810/amloop/loopbottom.jpg http://users.fulladsl.be/spb13810/amloop/loop83cm.jpg http://users.fulladsl.be/spb13810/amloop/loopbottom2.jpg (when the box is closed, you can put a radio on it, nicely positioned inside the loop) these formumla's say: http://www.mindspring.com/~loop_antenna/umr_emc_calc.htm some 15 turns... on a 2m diam loop ... I know about the computer flat cable trick... (I put the first formula in cm (100 cm = 1 meter) on http://users.fulladsl.be/spb13810/amloop.htm ) -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224109 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Elimination of CW is a loss in the number of ways we can communicate Date: Sat, 06 May 2006 02:16:35 -0700 Message-ID: <125oqbpg9m4d261@corp.supernews.com> References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> <445c1b4a$0$6152$39cecf19@news.twtelecom.net> <445c3238$0$6144$39cecf19@news.twtelecom.net> Tom Ring wrote: > > Bet no one from the antenna newsgroup even bothers to respond with > anything worthwhile. This is, after all, a group of people that thinks > the world ends at 10 meters. (Except for a very very few, and you know > I'm not speaking of you). I bet no one from the antenna newsgroup bothers to respond because the topic doesn't have anything to do with antennas. There are plenty of other newsgroups for those who favor the endless CW/no CW arguments. Roy Lewallen, W7EL Article: 224110 of rec.radio.amateur.antenna From: "Jozef" References: <1146887745.710806.22350@i40g2000cwc.googlegroups.com> Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Sat, 6 May 2006 08:11:29 -0400 Message-ID: <1146917413.147739@r2d2.vermontel.net> My $0.02: Passing the CW element requires the acquisition of a skill. Passing the "written" element requires memorizing answers to a test where the answers are handed out ahead of time. Some accomplishment, eh? Jozef WB2MIC "bradvk2qq" wrote in message news:1146887745.710806.22350@i40g2000cwc.googlegroups.com... > Dumb argument. > > CW is only being removed as a compulsory exam element. Oddly enough, > now that it is not compulsory, it's popularity is growing! > Article: 224111 of rec.radio.amateur.antenna From: Buck Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: <8p6p52hof5rqhlkttbkovt8q3r8ric48pa@4ax.com> References: <1146827830.022860.277130@j73g2000cwa.googlegroups.com> <445c1b4a$0$6152$39cecf19@news.twtelecom.net> <445c3238$0$6144$39cecf19@news.twtelecom.net> <125oqbpg9m4d261@corp.supernews.com> Date: Sat, 06 May 2006 08:50:13 -0400 On Sat, 06 May 2006 02:16:35 -0700, Roy Lewallen wrote: >Tom Ring wrote: >> >> Bet no one from the antenna newsgroup even bothers to respond with >> anything worthwhile. This is, after all, a group of people that thinks >> the world ends at 10 meters. (Except for a very very few, and you know >> I'm not speaking of you). > >I bet no one from the antenna newsgroup bothers to respond because the >topic doesn't have anything to do with antennas. There are plenty of >other newsgroups for those who favor the endless CW/no CW arguments. > >Roy Lewallen, W7EL Actually, I feel into this. However after posting this message I am killfiling the topic. 73/72 to all for now. On to important topics like how to get an antenna up in this restricted neighborhood without any trees! -- 73 for now Buck N4PGW Article: 224112 of rec.radio.amateur.antenna From: Grimly Curmudgeon Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Sat, 06 May 2006 13:54:29 +0100 Message-ID: References: <908n52hq9i6p209o65paqf8ha5sid5dhqf@4ax.com> We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember John Kasupski saying something like: >On Fri, 05 May 2006 19:01:42 +0100, Grimly Curmudgeon > wrote: > >>We were somewhere around Barstow, on the edge of the desert, when the >>drugs began to take hold. I remember Silent Key saying >>something like: >> >>>When CW is lost, new hams will be just like CB'ers and SWL's, or some >>>other lower life form of radio hobbiest. You name it. >> >>Go back to playing with the dinosaurs. > >Best reply of the bunch. Thank you. If I may add something to that... I wouldn't like to see Morse totally disappear, but I'm against its compulsion for trainees. I fully agree that in some conditions a Morse tone will get through where voice is an unintelligble mush, if heard at all, but apart from prisoners tapping out messages on pipes its days as an *essential* comms tool are pretty much over. We've all got to move with the times and these days Morse is on a par with a runner carrying a message in a cleft stick. There will be some who enjoy using it and I hope they find enough fellow enthusiasts of the arcane art to keep themselves happy while the rest of us communicate more naturally. -- Dave Article: 224113 of rec.radio.amateur.antenna From: "Ralph Mowery" References: <1146887745.710806.22350@i40g2000cwc.googlegroups.com> <1146917413.147739@r2d2.vermontel.net> Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: Date: Sat, 06 May 2006 14:12:03 GMT "Jozef" wrote in message news:1146917413.147739@r2d2.vermontel.net... > My $0.02: Passing the CW element requires the acquisition of a skill. > Passing the "written" element requires memorizing answers to a test where > the answers are handed out ahead of time. Some accomplishment, eh? > > Jozef WB2MIC CW is just memorizing the sounds . That is not a skill. Yes, I do have the 20 wpm extra. Got up to speed, passed the test, never used it on the air. I still listen to some about once a month just to see if I can still get any of the characters. A skill is more like repairing a piece of equipment or building something. Maybe even the ability to put together an interisting conversation instead of the usual WX and Signal reports. de KU4PT Article: 224114 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 11:08:25 -0400 From: jawod Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: Message-ID: <61370$445cbc13$453d9423$2432@FUSE.NET> Cecil Moore wrote: > Signal Chaser wrote: > >> "Brenda Ann" wrote in >> >>> Not everyone speaks readable English, but anyone that knows Morse can >>> copy any language and read it at their leisure. Also, those who don't >>> speak English well can often spell the words well enough to read... >>> >> In a way, it's sort of like sign-language. Two people that don't know >> each others tongue but know sign language can still communicate. > > > Of course, the same thing is possible on SSB communicating > phonetically. I don't think it is as effectice on SSB. Of course, you can use the symbols that were derived from CW (like QTH) but I think morse code is a more direct communication in these circumstances because it doesn't involve voice/pronunciation differences between languages. The symbols are universal and immediately understood. Phonetic usage (alpha bravo whiskey hotel etc) is primarily based upon English. Article: 224115 of rec.radio.amateur.antenna Message-ID: <445CBDBA.5060905@fuse.net> Date: Sat, 06 May 2006 11:16:10 -0400 From: jawod Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <_GR6g.4156$Vn.950@newsread4.news.pas.earthlink.net> <1146884369.627806.238470@u72g2000cwu.googlegroups.com> an_old_friend wrote: > Signal Chaser wrote: > >>"Ralph Mowery" wrote in >>news:nfL6g.5787$DT5.3176@newsread3.news.pas.earthlink.net: >> >> >>>and the code may soon not be >>>needed for the low bands. >> >> >>But we hope that won't happen though. > > yes we do > >>We already have CB for a codeless service. You want Ham radio to be like >>CB? > > > it will not be since you can't do lots of stuff on cb that you can on > ham radio > >>SC > > I think we need to face the fact that ham radio, in general, is not as necessary or as "needed" as it was even 20 years ago. It's a hobby. It remains a service but it is a hobby. CW,SSB and any other mode you choose is not that much NEEDED. CW being the simplest form, remains the form of choice when ALL infratructural resources are gone. Article: 224116 of rec.radio.amateur.antenna From: Jack Hamilton Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Mon, 01 May 2006 09:13:56 -0700 Message-ID: <7pcc529pkjai8it772egva9u2uisjmrm1p@4ax.com> References: Signal Chaser wrote: >In a way, it's sort of like sign-language. Two people that don't know >each others tongue but know sign language can still communicate. Actually, there are various sign languages, often corresponding to national languages, and I've been told that although they tend to have more in common than spoken languages, a person who can speak one can't necessarily understand the others. Jack Hamilton jfh@acm.org ----- Though in a state of society some must have greater luxuries and comforts than others, yet all should have the necessities of life; and if the poor cannot exist, in vain may the rich look for happiness or prosperity. The legistlature is never so well employed as when they look to the interests of those who are at a distance >from them in the ranks of society. It is their duty to do so; religion calls for it; humanity calls for it; and if there are hearts who are not awake to either of those feelings, their own interests would dictate it. Sir Lloyd Kenyon, Rex vs. Rusby, 1800 Article: 224117 of rec.radio.amateur.antenna From: mcalhoun@ksu.edu Subject: Re: J_Pole Trials and Tribulations Date: 6 May 2006 14:09:04 -0500 Message-ID: References: <1146008591.641742.237030@y43g2000cwc.googlegroups.com> <4tjt42lg6k5ustfmiljfkpiqdle084d0iq@4ax.com> <96N4g.77517$dW3.54166@newssvr21.news.prodigy.com> << I happen to like them as they can be made from common materials with << excellent ruggedness. References: <1146008591.641742.237030@y43g2000cwc.googlegroups.com> <4tjt42lg6k5ustfmiljfkpiqdle084d0iq@4ax.com> <96N4g.77517$dW3.54166@newssvr21.news.prodigy.com> >> The J-pole crowd seems to tout fantastic claims about this antenna and I >>....[snip].... >... my affinity for the j-pole comes from its simplicity and durability. >... Mounting is a dream -- it even works if you drop the low end into a plumbing vent pipe. (How would I know that? ;-) >....[snip].... I once made a J-pole from 300-ohm twinlead and tweaked it until it worked OK while hanging from the ceiling, but when I moved it over next to a wood-framed picture window (hung it from the window casing), the SWR went to pot. Did I do something wrong? (I concluded the J-pole must be VERY sensitive to its surroundings.) -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448 NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol) Article: 224119 of rec.radio.amateur.antenna From: mcalhoun@ksu.edu Subject: Re: "interesting" antenna design Date: 6 May 2006 14:27:45 -0500 Message-ID: References: <69488$4450c795$453d9423$12820@FUSE.NET> <12525ve803tkr07@corp.supernews.com> <3hd2525iugq7fnnabcpsqk32okj0ncklt7@4ax.com> <4454C4B7.4060503@fuse.net> >> I just think the great stories of rain gutters, chimneys, fire escapes, >> etc. reflect the spirit of individual experimentation that, to me, is >> the heart of ham radio. Maybe not the brain, but the heart. >You must love Kurt N. Sterba's tales of using bedsprings, >ladders, and garbage cans for antennas. And don't forget the (QST?) pictures of "car antennas" several years ago: two cars sitting almost bumper-to-bumper and fed with coax as a very-low dipole at the almost-touching bumpers. Truly a "car antenna" (but not very mobile)! -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448 NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol) Article: 224120 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <61370$445cbc13$453d9423$2432@FUSE.NET> Message-ID: Date: Sat, 06 May 2006 19:56:09 GMT jawod wrote: > I don't think it is as effectice on SSB. Of course, you can use the > symbols that were derived from CW (like QTH) but I think morse code is a > more direct communication in these circumstances because it doesn't > involve voice/pronunciation differences between languages. The symbols > are universal and immediately understood. Well then use PACTOR II with those symbols. PACTOR II will get through when CW fails. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224121 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: J_Pole Trials and Tribulations References: <1146008591.641742.237030@y43g2000cwc.googlegroups.com> <4tjt42lg6k5ustfmiljfkpiqdle084d0iq@4ax.com> <96N4g.77517$dW3.54166@newssvr21.news.prodigy.com> Message-ID: Date: Sat, 06 May 2006 20:00:06 GMT mcalhoun@ksu.edu wrote: > I once made a J-pole from 300-ohm twinlead and tweaked it until it worked > OK while hanging from the ceiling, but when I moved it over next to a > wood-framed picture window (hung it from the window casing), the SWR went > to pot. Did I do something wrong? What kind of metal was behind the window frame? -- 73, Cecil http://www.qsl.net/w5dxp Article: 224122 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 16:01:13 -0400 From: jawod Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <1146887745.710806.22350@i40g2000cwc.googlegroups.com> <1146917413.147739@r2d2.vermontel.net> Message-ID: pltrgyst wrote: > On Sat, 06 May 2006 15:35:46 GMT, "CW" wrote: > > >>Memorizing a sound is no more of a skill than memorizing an answer.... > > > But being able to pull up the correct characters from memory at the pace of an > incoming stream is a skill. > > I have an 85-year-old uncle who was a cw operator in the Pacific in WWII. He > hasn't done anything with cw since 1946, and he can still copy around 10 wpm > when I make him a bet. > > I can go for several years without hearing cw and still step in and copy 15wpm > easily. > > Those of you who once passed 20 wpm tests and now find it a challenge to see if > you "remember any of the characters" are simply not very bright. > > -- Larry > whatever Article: 224123 of rec.radio.amateur.antenna From: switcher Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into LW 216khz ! References: Date: Sat, 06 May 2006 22:26:08 +0200 Message-ID: In article , John Popelish wrote: > switcher wrote: > > > The loop is 2 x 3 meter of PVC tube, bended in a circle. > > There are now 3 turns. Guess ... how many turns to have the LW > > 153-279khz ??? > > If 3 turns resonated with about 11000 pF (your 10 nF plus about 1 nF > from the tuning capacitor) produces a resonance within that band, then > raising the turns to about 9 (3 times as much for about 3^2 times as > much inductance) would resonate at the same frequency with about 1/9th > as much capacitance (same L*C product). Of course, those extra turns > will also add quite a bit of stray capacitance between turns, so you > may not be able to reach the top of the band at minimum tuning > capacitance. > > What kind of insulation is on the wire in the big loop? Its thickness > and dielectric constant have a big effect on the total stray > capacitance each turn will add. I guess copper 0.7 mm, insulation soft plastic .25 mm -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224124 of rec.radio.amateur.antenna From: switcher Subject: If Amloop is LC circuit, what about RLC circuit ?? Date: Sat, 06 May 2006 22:38:43 +0200 Message-ID: a damped LC ??? Does it make sense to introduce a R in the LC circuit and use it as antenna ?? Does it change eg the Q ??? etc ... I have tried to put formula's here (look if they are right ! freq_low=Math.sqrt(1/(inductance*cap_high) - (resistance * resistance ) / (4 *inductance *inductance))/(2*Math.PI) freq_high=Math.sqrt(1/(inductance*cap_low) - (resistance * resistance ) / (4 *inductance *inductance))/(2*Math.PI) OK ??? ) http://users.fulladsl.be/spb13810/amlooprlc.htm A high R seems to lower the low freq, that's interesting ... original formula for LC circuits: (put R = 0 in previous, and you should get the same ....) http://users.fulladsl.be/spb13810/amloop.htm -- een appeltje te schillen met http://applefaulty.be http://users.fulladsl.be/spb13810/bwnl.htm Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen) http://www.apple.com/nl/support/imac/repairextensionprogram/ Article: 224125 of rec.radio.amateur.antenna From: Bob Downonit Message-ID: <2006050617232064440%Down@gagnet> References: Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Sat, 06 May 2006 21:23:10 GMT On 2006-05-04 20:15:41 -0400, Silent Key said: > What's the purpose of ham radio, To have fun talking about rigs and > weather, or to be able to communicate? > To be able to communicate when no one else can communicate and to advance > radio knowledge & theory? > What does part 97 say about this? Why does the ARRL ignore it? > > When CW is lost, new hams will be just like CB'ers and SWL's, or some > other lower life form of radio hobbiest. You name it. > SC > > > > Nonsense. Article: 224126 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 18:50:46 -0400 From: John Popelish Subject: Re: added 10 nF to my 1500-700Khz ant loop: -->> Result: i'm into References: Message-ID: switcher wrote: > In article , > John Popelish wrote: (snip) >>What kind of insulation is on the wire in the big loop? Its thickness >>and dielectric constant have a big effect on the total stray >>capacitance each turn will add. > > > I guess copper 0.7 mm, insulation soft plastic .25 mm Sounds like ordinary PVC insulated hook up wire. The PVC is a little lossy, but not too bad at this low frequency. You would have a lot more trouble with high capacitance if you were using enameled (magnet) wire. My favorite for such things is Teflon or Tefzel insulated wire (low loss and low dielectric constant), but it is expensive and hard to find. Another good, but hard to find insulation is polyethylene. It is sometimes used in low capacitance, data grade cables, but stripping out enough for this project would be a career. Do you think it is practical to pull 6 more turns through your pipe? Article: 224127 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: New program - PROPGATE Date: Sat, 06 May 2006 15:44:32 -0700 Message-ID: <125q9mmr06i31e1@corp.supernews.com> References: Have you measured the signal strengths from a few stations of known locations, power levels, and antenna gains, and compared them with your program's predictions? Roy Lewallen, W7EL Reg Edwards wrote: > For either line-of-sight or multi-hop propagation through the > ionosphere - > > - this apparently simple program computes path loss in dB between > transmitter and receiver, field strength at the receiving site, and > receiver S-meter readings. Transmitter power output can be varied > between 10 KW and 1 milliwatt. > > It is educational for newcomers and of assistance to DX and > line-of-sight experimenters. It illustates how S-meters OUGHT to work. > > Download program PROPGATE from website below in a few seconds and run > immediately. Its at the bottom of the list. > ---- > ........................................................... > Regards from Reg, G4FGQ > For Free Radio Design Software go to > http://www.btinternet.com/~g4fgq.regp > ........................................................... > > Article: 224128 of rec.radio.amateur.antenna From: John - KD5YI Subject: Re: New program - PROPGATE References: Message-ID: Date: Sat, 06 May 2006 23:04:08 GMT Reg Edwards wrote: > For either line-of-sight or multi-hop propagation through the > ionosphere - > > - this apparently simple program computes path loss in dB between > transmitter and receiver, field strength at the receiving site, and > receiver S-meter readings. Transmitter power output can be varied > between 10 KW and 1 milliwatt. > > It is educational for newcomers and of assistance to DX and > line-of-sight experimenters. It illustates how S-meters OUGHT to work. > > Download program PROPGATE from website below in a few seconds and run > immediately. Its at the bottom of the list. > ---- > ........................................................... > Regards from Reg, G4FGQ > For Free Radio Design Software go to > http://www.btinternet.com/~g4fgq.regp > ........................................................... > Are the formulae used in this program approximate and perhaps do not apply in circumstances in which you have no time (at this time in your life) to tell the "secrets" about? Without source code, it is difficult to "read between the lines". John Article: 224129 of rec.radio.amateur.antenna From: Jack Hamilton Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Date: Mon, 01 May 2006 16:04:26 -0700 Message-ID: References: <61370$445cbc13$453d9423$2432@FUSE.NET> "Dee Flint" wrote: > >"Cecil Moore" wrote in message >news:tb77g.11986$Lm5.649@newssvr12.news.prodigy.com... >> jawod wrote: >>> I don't think it is as effectice on SSB. Of course, you can use the >>> symbols that were derived from CW (like QTH) but I think morse code is a >>> more direct communication in these circumstances because it doesn't >>> involve voice/pronunciation differences between languages. The symbols >>> are universal and immediately understood. >> >> Well then use PACTOR II with those symbols. PACTOR II will >> get through when CW fails. >> -- > >Any rational evaluation of the modes available will show that there is a >combination of circumstances that make a specific mode the one that will >"get through". One can "prove" that their favorite mode is the one that >will get through under certain conditions. You are claiming that there are circumstances under which CW can be understood but none of the newer digital modes can? Assuming, of course, a skilled operator for CW and appropriate equipment for digital modes. Or even software for both. Jack Hamilton jfh@acm.org ----- Though in a state of society some must have greater luxuries and comforts than others, yet all should have the necessities of life; and if the poor cannot exist, in vain may the rich look for happiness or prosperity. The legistlature is never so well employed as when they look to the interests of those who are at a distance >from them in the ranks of society. It is their duty to do so; religion calls for it; humanity calls for it; and if there are hearts who are not awake to either of those feelings, their own interests would dictate it. Sir Lloyd Kenyon, Rex vs. Rusby, 1800 Article: 224130 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Elimination of CW is a loss in the number of ways we can communicate References: <61370$445cbc13$453d9423$2432@FUSE.NET> Message-ID: Date: Sat, 06 May 2006 23:26:41 GMT Dee Flint wrote: > Any rational evaluation of the modes available will show that there is a > combination of circumstances that make a specific mode the one that will > "get through". One can "prove" that their favorite mode is the one that > will get through under certain conditions. I have seen PACTOR II get through from Europe with 10 watts when there was no humanly detectable signal. All I did was choose the correct frequency and time based on a schedule. I detected absolutely no carrier on the S-meter or with my ears in CW mode. The PACTOR II signal was literally down in the noise but my SCS PTC-IIe somehow managed to dig it out. -- 73, Cecil http://www.qsl.net/w5dxp Article: 224131 of rec.radio.amateur.antenna From: Allisonnospam@nouce.bellatlantic.net Subject: Re: J_Pole Trials and Tribulations Message-ID: References: <1146008591.641742.237030@y43g2000cwc.googlegroups.com> <4tjt42lg6k5ustfmiljfkpiqdle084d0iq@4ax.com> <96N4g.77517$dW3.54166@newssvr21.news.prodigy.com> Date: Sun, 07 May 2006 00:39:24 GMT On Sat, 06 May 2006 20:00:06 GMT, Cecil Moore wrote: >mcalhoun@ksu.edu wrote: >> I once made a J-pole from 300-ohm twinlead and tweaked it until it worked >> OK while hanging from the ceiling, but when I moved it over next to a >> wood-framed picture window (hung it from the window casing), the SWR went >> to pot. Did I do something wrong? > >What kind of metal was behind the window frame? Some wood frame windows have nice 10" long weights in both sides and metal screens on the outside. He mentions that it was tweeked till it worked "OK". that does not mean it was matched or centered in the band. I've found most Jpoles I've checked for people at FD were usually badly mistuned. the problem usually is they followed the directions exactly but for one thing they could not control VF for various brands twinlead is all over the map and that does effect tuning and stub position. The other is often most do not have a usable VHF swr measuring device. I've found the twinlead/ladderline Jpole the hardest to reproduce without testing each one and tuning it. The copper pipe ones if all measurements are the same, each one will be the same. As to the /4WL ground plane. Same deal everyone I've tested for friends needed a clipping or radial bent down to the correct angle. A few used insulated wire (Works but the lengths change!). Again most of those were people that didn't have a usable VHF SWR measuring device of any kind of if they did could not interpret the data. Measurements are required. A suitable SWR meter of some form is needed or your just guessing. Allison Article: 224132 of rec.radio.amateur.antenna From: Allisonnospam@nouce.bellatlantic.net Subject: Re: If Amloop is LC circuit, what about RLC circuit ?? Message-ID: <6kgq52prlhfbda18grk4n7iv53l420knum@4ax.com> References: Date: Sun, 07 May 2006 00:41:35 GMT Adding R will lower Q and make the loop less selective. There is a BUT. Adding R also adds losses and will lower signal, sharply. Ideally you want to reduce resistance anyway possible. Allison On Sat, 06 May 2006 22:38:43 +0200, switcher wrote: >a damped LC ??? >Does it make sense to introduce a R in the LC circuit and use it as >antenna ?? >Does it change eg the Q ??? etc ... > >I have tried to put formula's here >(look if they are right ! >freq_low=Math.sqrt(1/(inductance*cap_high) - (resistance * resistance ) >/ (4 *inductance *inductance))/(2*Math.PI) >freq_high=Math.sqrt(1/(inductance*cap_low) - (resistance * resistance ) >/ (4 *inductance *inductance))/(2*Math.PI) > >OK ??? >) >http://users.fulladsl.be/spb13810/amlooprlc.htm > > >A high R seems to lower the low freq, that's interesting ... > > > >original formula for LC circuits: (put R = 0 in previous, and you should >get the same ....) > >http://users.fulladsl.be/spb13810/amloop.htm Article: 224133 of rec.radio.amateur.antenna From: "OZUser" Subject: HF Mobile - Grounding Antenna when stationary Message-ID: <1146965914.944527@teuthos> Date: Sun, 7 May 2006 10:33:51 +0930 As an avid 4WD SUV owner I do a lot of outback travelling (Austrlian Deserts, Cape York, Kimberly Coast) and as such have a Barrett 950 HFradio &Barrett 910 Autotune antenna installed for comms. Would it be preferable when camped / stationary to earth the vehile to a "ground" ground = what I am looking for is a better receive signal ????? Article: 224134 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: HF Mobile - Grounding Antenna when stationary Date: Sat, 06 May 2006 18:21:13 -0700 Message-ID: References: <1146965914.944527@teuthos> ORIGINAL MESSAGE: On Sun, 7 May 2006 10:33:51 +0930, "OZUser" wrote: >As an avid 4WD SUV owner I do a lot of outback travelling (Austrlian >Deserts, Cape York, Kimberly Coast) and as such have a Barrett 950 HFradio >&Barrett 910 Autotune antenna installed for comms. > >Would it be preferable when camped / stationary to earth the vehile to a >"ground" ground = what I am looking for is a better receive signal ????? > > *********** REPLY SEPARATOR *********** Improving the ground will increase the received signal strength but will also increase the background noise as well, so the signal to noise ratio won't change much if any. In other words, no real improvement. However, an improved ground will improve your transmitted signal, especially on the lower frequencies - 7MHz and down. Best of all though, would be to string up a temporary dipole or inverted vee. Bill, W6WRT Article: 224135 of rec.radio.amateur.antenna From: "Frank" References: <1146933351.476896.129780@g10g2000cwb.googlegroups.com> Subject: Re: question: NEC2 w/ ground parms. Message-ID: Date: Sun, 07 May 2006 03:09:30 GMT "rjtucke" wrote in message news:1146933351.476896.129780@g10g2000cwb.googlegroups.com... > I'm trying to model a 3-wire dipole over finite ground in NEC2. > However, the SOMNEC output keeps clashing with the data in > my main code (GN card), though I input the same values. > Error is: > ERROR IN GROUND PARAMETERS - > COMPLEX DIELECTRIC CONSTANT FROM FILE IS 2.59287E-09-1.09717E+00 > REQUESTED 1.20000E+01-7.00000E-02 > > Any thoughts? > > Ross Tucker > Ariz. State Univ. Have you tried manually calculating the complex dielectric constant? If there is a difference greater than 10E-3 from the GN card an error message is generated. >From your information above the difference is >> 10E-3. pp 55, 56 NEC 2 Users Manual. Regards, Frank Article: 224136 of rec.radio.amateur.antenna From: Telamon Subject: Re: If Amloop is LC circuit, what about RLC circuit ?? References: Message-ID: Date: Sun, 07 May 2006 03:17:05 GMT In article , switcher wrote: > a damped LC ??? Does it make sense to introduce a R in the LC circuit > and use it as antenna ?? Does it change eg the Q ??? etc ... It depends on what you want. Maybe the bandwidth is to narrow or the tuning action is so sharp it is hard to peak it. You add resistance and the peak does go down but the bandwidth also widens. -- Telamon Ventura, California Article: 224137 of rec.radio.amateur.antenna From: Telamon Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. References: <2006050617232064440%Down@gagnet> Message-ID: Date: Sun, 07 May 2006 03:34:41 GMT In article <2006050617232064440%Down@gagnet>, Bob Downonit wrote: > On 2006-05-04 20:15:41 -0400, Silent Key said: > > > What's the purpose of ham radio, To have fun talking about rigs and > > weather, or to be able to communicate? To be able to communicate > > when no one else can communicate and to advance radio knowledge & > > theory? What does part 97 say about this? Why does the ARRL > > ignore it? > > > > When CW is lost, new hams will be just like CB'ers and SWL's, or > > some other lower life form of radio hobbiest. You name it. SC > > > > > > > > Nonsense. It is nonsense in rec.radio.shortwave. Please drop this news group from the thread. Another thread about CW is pointless. You guys have posted the same comments hundreds of times on this subject. -- Telamon Ventura, California Article: 224138 of rec.radio.amateur.antenna Date: Sat, 06 May 2006 23:29:01 -0500 From: Tom Ring Subject: Re: J_Pole Trials and Tribulations References: Message-ID: <445d778d$0$1017$39cecf19@news.twtelecom.net> jimbo wrote: > I have been trying to get an acceptable 2 meter antenna installed in my > attic. A J-Pole seemed to me the best solution for my attic space. You > jimbo - AJ7IM Here is a link to one I have had good luck with. Works quite well out of the box. I use two chaokes, one at the base, and one 19 inches below that. You may need to trim the length of the half wave section, so cut it a smidge long. http://www.hamuniverse.com/2mladjpole.html tom K0TAR Article: 224139 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <2uA6g.8331$QP4.4556@fed1read12> <_I2dnfwDCNN4bcbZRVn-jg@comcast.com> Subject: Re: Elimination of CW is a loss in the number of ways we can communicate with other. Message-ID: Date: Sat, 6 May 2006 23:08:30 -0700 "Dee Flint" wrote in message news:_I2dnfwDCNN4bcbZRVn-jg@comcast.com... > > "Sal M. Onella" wrote in message > news:2uA6g.8331$QP4.4556@fed1read12... > > > > "Silent Key" wrote in message > > news:NOw6g.6936$An2.3601@newsread2.news.pas.earthlink.net... > >> What's the purpose of ham radio, To have fun talking about rigs and > >> weather, or to be able to communicate? > >> > >> To be able to communicate when no one else can communicate and to advance > >> radio knowledge & theory? > >> > >> What does part 97 say about this? Why does the ARRL ignore it? > >> > >> When CW is lost, new hams will be just like CB'ers and SWL's, or some > >> other lower life form of radio hobbiest. You name it. > >> > >> SC > > > > I should be able to keep this from getting to me, but sometimes I just > > feel > > like responding to the attempted intimidation by these elitists. > > > > Mate, your key is only silent from the neck, up. > > > > Due to dyslexia, I am unable to learn much Morse Code. I can consistently > > recognize about half of the alphabet and none of the numbers. Morse Code > > might as well be edoC esroM for all the good it will ever do me. > > > > Actually your own words have proven that you can learn it. You say you can > consistently recognize about half the alphabet. So you have demonstrated > your ability to learn it. > > Perhaps you just haven't spent enough time on it or used a poor training > method (there's way too many of those around). Most people's expectations > of how long it will take are unrealistically short. For the average person, > it will take 1/2 hour per day every day for 60 days. > > Now writing it down could be a problem due to dyslexia but there are ways > around that. You don't have to write it down. You can ask to be allowed to > say the characters into a tape recorder. You could dictate the characters > to a VE to write down for you. You could simply jot down notes and answer > the questions and not worry about solid copy. Again if there is a risk of > writing it backwards, you could have the VE write down what you tell > him/her. Naturally such accomodations have to be set up in advance. > > > In spite of this, I manage to be a responsible member of the ham radio > > community and I'm damn proud of my service to RACES, to my club as its > > treasurer and to the county as a volunteer communicator. My UHF/VHF > > points > > in last year's Field Day exceeded the points of our HF stations combined. > > Lower life form, indeed! The nerve of you! > > > > You must have run into some crummy people. That is not necessarily true of > all groups. > > > You may get down off your high horse (or should it be "High Morse"?) and > > apologize for all those jabs any old time it pleases you. I'll be here. > > > > You are painting with a very broad brush. There are many amateurs who do > not jab the Technicians. These days the membership of most clubs is about > half Technicians. Perhaps you need to run with a different club. > > Dee, N8UZE > > Dee, please go back and re-read Silent Key's original post and my response. I was reacting ONLY to that one person's remarks. I was actually narrow-brushing. While I'm an officer in just one club, I am in three and none of them have any crummy people -- and I certainly agree with you that many amateurs don't jab the techs. In fact, I encounter practically total acceptance. That's why Silent Key stood out. With regard to can/can't learn, I have the most problems with the characters that are four or more elements long. dit-dah-dah-dit and dah-dit-dit-dah are different, but I can't tell you what they are. I think one of them is "P" because I remember the symmetry. Transcribing is not the problem. If I hear dit-dah, I can write A. But if I hear dit-dah-dah-dah-dah or dah-dit-dit-dit-dit, I don't know what to write, because I don't know what those are. I cannot store the memory of what those sounds mean. Since you (apparently) don't have the problem, you won't relate. And it isn't a lack of time or effort. I have been at this since 1993. Many methods. No appreciable successes. (I did get "D" from "dog-did-it" and "Q" from "pay-day-to-day" -- a couple of real triumphs, eh? [sarcasm intended]) This is no picnic. Thanks for understanding. 73, "Sal" Article: 224140 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: New program - PROPGATE Date: Sat, 06 May 2006 23:11:01 -0700 Message-ID: <125r3rrno18f19d@corp.supernews.com> References: <125q9mmr06i31e1@corp.supernews.com> I interpret that as a "no". Roy Lewallen, W7EL Reg Edwards wrote: > Roy, would you like your money back? > > Article: 224141 of rec.radio.amateur.antenna From: "Kevin & Natalia" Subject: 3 Wired Antenna Build. Date: Sun, 7 May 2006 21:42:09 +1200 Message-ID: <1146994748.542651@ftpsrv1> Hi, I want to build a new antenna. The design I have seen is a 3 wired type each side, where the 3 wires join together at each end. There are two of these, and the two are centred, and fed with coax. The one I saw was flat, but understand that they could be in-verted. I am hoping it is multi-band :) I would like to find information on this antenna, measurements, and construction hints. If anyone can help, could you please advise. Regards in advance. Kevin, ZL1KFM. Article: 224142 of rec.radio.amateur.antenna From: "Guy" References: <2006050617232064440%Down@gagnet> Subject: Re: Elimination of CW is the only way we can make it fair Message-ID: Date: Sun, 7 May 2006 06:39:32 -0500 "Telamon" wrote in message news:telamon_spamshield-1B2945.20344106052006@newsclstr02.news.prodigy.com... > > Another thread about CW is pointless. You guys have posted the same > comments hundreds of times on this subject. > > -- > Telamon > Ventura, California Amen! I used to be a staunch defender of CW. We lost the 20, we lost the 13, we are going to lose the 5. In today's age of materialism, self created rights and the liberal ideals of fairness, I'm just waiting for the removal of all testing requirments. Just show up, mark A, B, C or D on 10 questions (no grading, just turn it in) and then get a certificate of attendance, a blue ribbon that says 1st place and a 1x2 vanity call sign. Guy