Article: 97802 of rec.radio.amateur.homebrew From: Larry Gagnon Subject: Re: Using Garage for Ham Shack Date: Sat, 01 Jul 2006 09:04:54 -0700 Message-ID: References: <1151699486.365534.315290@y41g2000cwy.googlegroups.com> On Fri, 30 Jun 2006 13:31:26 -0700, Alex wrote: > Hi Everyone, > > I hope to get my technician license for the first time in a month or > two, and I've been thinking of setting-up shop in the garage once I > start getting some radios and equipment. > > Some questions though, the garage is on the corner of our brick house > with one smaller window (facing front of house), two walls are interior > walls with other two being exterior (one having garage door). Andy: my answer is completely lateral thinking, but if for some reason the whole ham shcak thing at your home doesn't work out what about HF/VHF mobile from your car (with A/C of course), or join your local ham radio club that has its own station. I know from experience that many club stations often get very little use! Good luck with your solutions... Larry VE7EA Article: 97803 of rec.radio.amateur.homebrew From: Bruce in Alaska Subject: Re: IEEE Standard for RF Safety Levels References: <1151772940.769643.43270@v61g2000cwv.googlegroups.com> Message-ID: Date: Sat, 01 Jul 2006 17:56:22 GMT In article <1151772940.769643.43270@v61g2000cwv.googlegroups.com>, "Dr. Jeff" wrote: > Can anyone refer me to a link where I can access (for FREE) the "IEEE > Standard for Safety Levels with Respect to Human Exposure to Radio > Frequency Electromagnetic Fields"; C95.1-1992 or similar document that > covers exposure guidelines for specific RF frequencies. > I'm detecting extremely high levels of 4.2 to 4.5 Mhz. RF from a Cable > TV companys pole mounted equipment in front of my home. > > Jeff > Anything that is radiating from a "Cable Tv" cable will be FAR below the Human Exposure Safety Level. The signal levels on those distribution feeds rarely ever get above +10dbm and the frequency your seeing is usually used in the "Return to Headend" direction which will have less power than the Main Distribution Channels. The FCC has very strict guidelines for ammount of RF Radiation allowed to leak from those type systems, so I would contact the Cable company and let them know, but it isn't a Health Hazard, or even close. Bruce in alaska a reTIRED FCC Field Agent..... -- add a <2> before @ Article: 97804 of rec.radio.amateur.homebrew From: fmmck@aol.com (Fred McKenzie) Subject: Re: IEEE Standard for RF Safety Levels Date: Sat, 01 Jul 2006 14:54:01 -0400 Message-ID: References: <1151772940.769643.43270@v61g2000cwv.googlegroups.com> In article <1151772940.769643.43270@v61g2000cwv.googlegroups.com>, "Dr. Jeff" wrote: > Can anyone refer me to a link where I can access (for FREE) the "IEEE > Standard for Safety Levels with Respect to Human Exposure to Radio > Frequency Electromagnetic Fields"; C95.1-1992 or similar document that > covers exposure guidelines for specific RF frequencies. > I'm detecting extremely high levels of 4.2 to 4.5 Mhz. RF from a Cable > TV companys pole mounted equipment in front of my home. Jeff- I don't know about the IEEE standard, but you might check out the FCC Safety web site at www.fcc.gov/oet/rfsafety and look for their Bulletins 56 and 65. In particular, Bulletin 65 describes alloowable levels and how to measure them, for various frequencies. Bulletin 65 may have a reference to the IEEE standard you are looking for, if it exists. Fred Article: 97805 of rec.radio.amateur.homebrew From: John - KD5YI Subject: Re: IEEE Standard for RF Safety Levels References: <1151772940.769643.43270@v61g2000cwv.googlegroups.com> Message-ID: <9aCpg.1822$uC3.1055@trnddc08> Date: Sat, 01 Jul 2006 21:54:13 GMT Dr. Jeff wrote: > Can anyone refer me to a link where I can access (for FREE) the "IEEE > Standard for Safety Levels with Respect to Human Exposure to Radio > Frequency Electromagnetic Fields"; C95.1-1992 or similar document that > covers exposure guidelines for specific RF frequencies. > I'm detecting extremely high levels of 4.2 to 4.5 Mhz. RF from a Cable > TV companys pole mounted equipment in front of my home. > > Jeff > You are "detecting extremely high levels of 4.2 to 4.5 Mhz. RF"? How do you know? Please give some numbers. In any units with which you are familiar. Article: 97806 of rec.radio.amateur.homebrew From: ken scharf Subject: Re: Using Garage for Ham Shack References: <1151699486.365534.315290@y41g2000cwy.googlegroups.com> Message-ID: Date: Sat, 01 Jul 2006 21:44:58 -0400 Alex wrote: > Hi Everyone, > > I hope to get my technician license for the first time in a month or > two, and I've been thinking of setting-up shop in the garage once I > start getting some radios and equipment. > > Some questions though, the garage is on the corner of our brick house > with one smaller window (facing front of house), two walls are interior > walls with other two being exterior (one having garage door). > > My thought is if I insulate the attic and the one exterior wall without > the garage door then replace my aging garage door with a better sealing > one, that should do the trick -- right? As for heating and cooling, > i'm in central texas, and our summers do get hot. I don't think our > A/C in the house could pump out enough cool air to cool an additional > 430sqft, so any suggestions for that? The only window is on front of > house, so don't want to use window unit. I have a radiant heater I've > used in there for winter, and it works well. > > Thanks for any suggestions or ideas ... we don't park our cars in the > garage, and I hope to build a small shead in the back yard for the > mowers and such -- so that's 430sqft of space that's going to waste. > > Thanks again and take care --- > > Alex > Garage doors lack insulation, but you can do something about that. I live in South Florida, and while it doesn't get as hot as in Texas, it does get hot. We added insulation to our metal garage door in the form of Styrofoam insulating panels slipped into the inside of the door ducktaped in place. Fiberglass insulation with the cardboard backing would work as well. (Which has the better R value??). You might have to re-balance the door after adding the insulation, but in our case the garage door opener didn't seem to care and isn't straining. The insulation lowered the temperature in the garage during the summer by at least 10 degrees F. Article: 97807 of rec.radio.amateur.homebrew From: nospam@nouce.bellatlantic.net Subject: Re: Spurs on mixer output Message-ID: References: <9c0u7e.qnd.ln@tg6124.ab0wr.net> <1uudnfjaxZcAkjjZnZ2dnUVZ_vWdnZ2d@comcast.com> Date: Sun, 02 Jul 2006 02:15:07 GMT Not to belabor but as explanation. I use Free Agent and it displays in indented threaded form so your reply was nested two deep from my first reply posting. Allison Kb1GMX On Sat, 1 Jul 2006 14:50:17 -0500, "Pete KE9OA" wrote: >This thread is directed at the author, not you. The purpose of my posting in >the latest position of the thread is to move things in a chronological >order. The original poster knows how to read, so it is quite possible that >this person won't miss my posting. > >Pete > > wrote in message >news:r77ba2dqivor2ss3msqp48u3lqm3962r76@4ax.com... >> On Fri, 30 Jun 2006 06:48:45 -0500, "Pete KE9OA" >> wrote: >> >>>What kind of spectrum analyzer are you using? What are the front end >> >> I'm not using one the author of the thread is. >> >>>attenuator settings on the spectrum analyzer? What is your reference >>>level? >> >> Ask him not me. >> >>>All of these things, especially the front end attenuator settings, can >>>affect your result. If the 1st mixer in the spectrum analyzer is driven >>>into >>>nonlinearity, you can see all kinds of IMD products that are generated in >>>the analyzer itself. >>>Also, why are you doing this test with the RF port of the mixer terminated >>>in 50 Ohms? This type of termination is only used when doing either >>>return >>>loss tests or noise balance tests. >>>If you are driving the SBL-1 mixer with +7 to +9dBm of LO level and you >>>are >>>driving the RF port with a signal that is at least 20dB below the 1dB >>>compression point of the SBL-1, the main things you should see at the I.F. >>>port are a supressed LO signal, an upper sideband that is about 7dB lower >>>in >>>level than the RF injection level, and a lower sideband that is also about >>>7dB lower in level than the RF injection level. >>>The 1dB compression point on the SBL-1 is about 0dBm, so I would set the >>>level to the RF port at -20dBm. If you go above this level, you will see >>>higher conversion loss, and possibly more IMD products at the I.F. port of >>>the mixer. >>>In conclusion, make sure that the IMD isn't being generated in your test >>>setup, and make sure that you are not exceeding the recommended RF input >>>level to the SBL-1. >>> >>>Pete >> >> You top posted to a reply that I'd posted to and your context is way >> off as a result. Go bat to the root of the thread and read the >> posting again. >> >> Briefly, he's seeing spurs every 25 or 50 khz with a LO in the 45mhz >> region and NO RF on the input (unterminated RF port). >> >> Allison >> >> >>> >>> wrote in message >>>news:p9o5a21152qsldg22fqccf0tm1ba7grf2d@4ax.com... >>>> On Wed, 28 Jun 2006 07:43:20 -0500, tim gorman >>>> wrote: >>>> >>>>>john wilkinson wrote: >>>>> >>>>>> >>>>>> >>>>>> Hi, >>>>>> If I feed my second mixer into a spectrum analyser, and inject a >>>>>> 44.545MHz >>>>>> LO, with no power to the first IF stage, I see spurs at about 48-50KHz >>>>>> intervals on the mixer output, from 0 to the 455KHz normal output >>>>>> freq. >>>> >>>>> >>>>>> The mixer is an SBL-1. >>>>>> >>>>>> Any ideas as to where these are comming from? >>>>>> >>>>>> Best regards, >>>>>> John >>>>> >>>>>A couple of observations. >>>>> >>>>>If you simply disconnected the second mixer from the 1st mixer then it >>>>>sounds like you do not have the output of the 1st mixer properly >>>>>terminated. Unless, that is, the spectrum analyzer provides a good 50ohm >>>>>termination in the probe. The SBL-1 is a double-balanced mixer but in >>>>>order >>>>>to get the "balance" to work right you must properly terminate *all* >>>>>ports. >>>>>Otherwise all kinds of impedances can be "thrown" back to the other >>>>>ports - >>>>>causing all kinds of problems with attached LO's and RF stages. >>>>> >>>>>Regularly spaced spurs from DC to 455khz does not sound like spurious >>>>>mixing >>>>>products. It sounds more like an oscillator being driven into saturation >>>>>causing square waves to be produced which are providing regular harmonic >>>>>outputs. This could be a product of poor terminations on the mixer >>>>>ports. >>>> >>>> Tim, the LO is 45.455 (or 44.545) either way there should be no LF >>>> outputs from the mixer below the LO injection unless it's a spur on >>>> the LO. >>>> >>>>>Directly connecting the output of a SBL-1 to the input of another mixer, >>>>>even another SBL-1, is not recommended either. The SBL-1 does not have >>>>>built-in terminations. A good, symmetric, 50ohm 3db pad between the >>>>>stages >>>>>would provide a much better setup and would not significantly impact >>>>>your >>>>>overall noise factor. Be sure and connect your spectrum analyzer to the >>>>>far >>>>>side of the pad. >>>> >>>> Thats true though his testing is with a 20db IF after it and one would >>>> hope that does present a 50ohm match to the IF port. Usually if the >>>> poarts are badly matched the mixing spurs are greater and the port >>>> to port isolation go to pot. If the only thing going in is the LO >>>> then likely the LO is the source but if there is gain flollowing then >>>> the gain stage is also suspect. >>>> >>>> I've worked with enough SBL1 and MD108s and all their similar DBMS >>>> to know the SBL1 in this case is not the offendor Even if >>>> misterminated. Likely causes are the 45mhz filter is looking reactive >>>> to the IF amp and the IF is unstable (makes a fine OSC) or there is >>>> some other source of RF that is unaccounted for (spurs). >>>> >>>> >>>> Allison >>>> Kb!GMX >>> >> > Article: 97808 of rec.radio.amateur.homebrew From: "hamguy1" Subject: looking for help with icom725 internal power supply Date: Sun, 2 Jul 2006 15:29:27 +1000 Message-ID: <44a759b4$0$22358$afc38c87@news.optusnet.com.au> hi ham radiogroups, im after the internal power control or alc inside of a icom725 hf transceiver the radio is doing way to much power for the power supply, it currently is doing 150 watts it needs to be turned back down to around 100 watts .thanks in advance david from nsw australia . Article: 97809 of rec.radio.amateur.homebrew From: David Subject: Help with Mosfet mixer Message-ID: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> Date: Sun, 02 Jul 2006 05:53:05 GMT I have constructed a Mixer for a VHF receiver (150MHz). The IF frequency is 45 MHz and LO is 105 MHz. Having not made a mixer before, I copied a typology directly from one of my fundamental electronics books. The layout is... RF signal into Gate 2 of BF998. Source has 100R Par with 1n to ground. G1 has 47K to ground and 100p to LO signal (I am using a sig gen for testing). The drain has a Tuned circuit consisting of 100nH and 125pF. A 1k resistor is across the coil to provide approx. 800 Ohms needed to interface to a 4-pole crystal filter. For testing I used a tap-C down to 50 Ohms from the 800R tank in the drain of the mixer BF998. I observe the frequencies coming out of the mixer when I inject the 150 MHz RF signal and find I can tune the 45MHz for a peak no problem. There do not appear to be any instabilities. The gain of the preceding stages (Input single tuned filter, MOSFET RF amp and Double Tuned Circuit) is around 24dB. When I add the mixer I find the total system gain is the same (24dB), The mixer seems to be mixing but adding no gain or loss. I also wonder where the mixer MOSFET is getting bias (from the LO ?) because the mixer stage doesn't appear to be drawing any current. I found the max. gain at the mixer output was when the LO level was anywhere from -5 to 0dBm. Would someone please mind explaining how the bias of the mixer should be applied and how much gain/loss I should expect. ( i hope I am asking the right questions here as have no previous experience with a discrete mixer). Thank in advance. Regards David Article: 97810 of rec.radio.amateur.homebrew From: Paul Keinanen Subject: Re: Using Garage for Ham Shack Message-ID: <1offa257jehmf67c1up3gqnfoes0e749ia@4ax.com> References: <1151699486.365534.315290@y41g2000cwy.googlegroups.com> <1151713216.174488.87780@d30g2000cwa.googlegroups.com> Date: Sun, 02 Jul 2006 15:52:43 +0300 On 30 Jun 2006 17:20:16 -0700, "AndyS" wrote: > Here is a suggestion that you might consider.... Wall off a closet >sized part of your garage, either with cheap panelling or maybe >plastic curtains, and get a Home Depot $70 air conditioner to use >just for that part..... Also good for space heater in winter.... Isolating a small volume from the garage makes sense since now the thermal resistance of the external wall and the closet walls are in series, thus reducing the heat leakage from the outside to the operating position and hence, reducing the heat that needs to be removed by the air conditioner. Since the closet walls are much smaller than the garage wall inside dimensions, for a specific amount of isolation material (and cost) much better isolation can be obtained by isolating the closet than isolating the whole garage. > Perhaps you can make sliding curtains like they do around hospital >beds..... A little 5000 BTU unit will cool the hell out of a small >closet-like >area, even if it is poorly insulated and leaks like hell.... The air >condx >can be mounted on a little dolly or something......venting into the >rest >of the garage. And slid off on the side when not in use... Venting into the rest of the garage does not make sense, especially with light closet walls, since this would be equivalent to an electric or acoustic short circuit. If you look at the situation from the rest of the garage, the heat >from the closet will enter the larger garage space, as well as the power required to run the air conditioner, as well as the leakage from the outside world through the garage walls. The rest of the garage will get very hot and if the closet walls are light, leak back into the closet, requiring more air conditioner power to remove it etc. The temperature of the rest of the garage will continue to rise, until the temperature is sufficiently _above_ the outside temperature and sufficient amount of thermal energy will flow _out_ through the garage external walls. Two ways to avoid this problem, one is to let the closet air conditioner pump the heat to the outside air or if the heat is pumped into the rest of the garage, at least open the garage door and use sufficiently good isolation in the closet walls to keep the air conditional power requirements at a reasonable level. After all, air conditioning is a similar problem as thermal management in any semiconductor systems, which use the analogies with resistances/conductances (thermal isolation/conduction) and capacitances (specific heat x mass). Paul OH3LWR Article: 97811 of rec.radio.amateur.homebrew From: ken scharf Subject: Re: Using Garage for Ham Shack References: <1151699486.365534.315290@y41g2000cwy.googlegroups.com> Message-ID: Date: Sun, 02 Jul 2006 10:59:17 -0400 Highland Ham wrote: >> Garage doors lack insulation, but you can do something about that. >> I live in South Florida, and while it doesn't get as hot as in Texas, >> it does get hot. We added insulation to our metal garage door in the >> form of Styrofoam insulating panels slipped into the inside of the door >> ducktaped in place. Fiberglass insulation with the cardboard backing >> would work as well. (Which has the better R value??). You might have >> to re-balance the door after adding the insulation, but in our case >> the garage door opener didn't seem to care and isn't straining. The >> insulation lowered the temperature in the garage during the summer by >> at least 10 degrees F. > ================================ > Normally this would be OT in this NG ,but mentioning styrofoam = > polystyrene , it is veeeeeeeeeeeeeeery flammable and if used in an > enclosed environment ,people inside would be in real trouble when a fire > broke out. Insulating material should be fireproof or at least flame > retardent while not emitting toxic/suffocating fumes. > > Frank GM0CSZ / KN6WH Styrofoam type insulating material that is designed for the purpose is made in a fire-retardant form. You have to buy the material made for the purpose!!! Article: 97812 of rec.radio.amateur.homebrew From: gwatts Subject: Re: looking for help with icom725 internal power supply References: <44a759b4$0$22358$afc38c87@news.optusnet.com.au> Message-ID: Date: Sun, 02 Jul 2006 15:30:57 GMT hamguy1 wrote: > hi ham radiogroups, im after the internal power control or alc inside of a > icom725 hf transceiver the radio is doing way to much power for the power > supply, it currently is doing 150 watts it needs to be turned back down to > around 100 watts .thanks in advance david from nsw australia . > > Go to http://www.icom.co.jp/world/support/index.htm click on 'Manuals,' agree to the license, scroll down to 'Amateur,' download the manual for the IC-725, look at page 31 (34 in the Acrobat window). I think you may be interested in 'R210' for the 100W power adjust. Watch the current, 73! W8LNA Article: 97813 of rec.radio.amateur.homebrew From: nospam@nouce.bellatlantic.net Subject: Re: Help with Mosfet mixer Message-ID: <3v5ga253acrcja7n3igmui3tq30tp0mm8o@4ax.com> References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> Date: Sun, 02 Jul 2006 19:00:59 GMT On 2 Jul 2006 10:27:37 -0700, "AndyS" wrote: > >Andy comments: > > I haven't used that particular dual gate Mosfet, but I will tell you >how I have used 3n140, 3n141, and others: > > G2 was used as the LO and was bias at around 3 volts DC with >resistors. The LO was cap coupled in at a leveL of about 2.5 Vrms. >It is useD as a switching signal to drive the MOSFET into and out >of conduction. It takes very little power from the LO, but the >2.5 Vrms swing was needed... > > G1 was used as the RF port. G1 and the source were biased >pretty much as you described. > > The drain was similar to your design. While using a 1K resistor >gives >a great source impedance to the xtal filter, it also absorbs most of >the signal.... If I remember, the output Z is 9 or 10 k for the devices >I used. I would use maybe a 7.5 K resistor and then impedance >match in the tuned circuit to get the source right. This usually took >some experimentation. Since the drain output was tuned to a different >frequency than the LO or the RFin, I never had a stability problem. >Power gains of 15 to 20 db were very common... ( Note , I said >POWER gain, and not voltage gain , which could be anything... ) > > > > Maybe my experience is outdated with the newer Mosfets, but I >have never seen, or used a circuit that put the LO on G!.... It was >always on G2.. I used dual gate mosfets to build receiver front >ends and mixer from about 1967 to about 1990. Then I started >using doubly balanced stuff like SBLs and MDs ..... I followed them >with a nice amplifer and good termination.....It costs a little more, >but the designs were always more stable and gave better >performance..... > > I hope this helps. Perhaps others here have used your particular >device and can give better guidance... > > Andy W4OAH Your experience is like mine and holds well for current generation DGfets or even a pair of casoded Jfets. Allison Article: 97814 of rec.radio.amateur.homebrew From: David Subject: Re: Help with Mosfet mixer References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> Message-ID: Date: Sun, 02 Jul 2006 22:45:57 GMT I noted in We Hayward's book "Experimental Methods in RF Design" that he suggests the gain of a Dual Gate Mosfet in a mixer circuit is about 1/4 of the gain of the same device in an RF amp circuit. If this is true then the 6dB gain I now see in the mixer stage would be about right. I cranked up the LO level and now have +/- 4V on G2. I tried biasing the Gate up to 3 but it made no difference than when just 47K to ground bias was used on G2. The main issue I am having now is matching to the 4-pole filter. I have tried several approaches and the performance is disgusting. The current mixer to filter circuit is.... This "should" have matched down to 800R 100nH (Q=100) inductor to Vcc from Drain 6-30p trimmer to ground from drain Split capacitor tap from drain to ground (220pF in series with 200pF) 1st filter, 4p7 to ground between 1st and second filter. Output match to 50R from 800R for testing... 100nH to ground from filter output 82pF to ground 6-30p trimmer to ground 15pF in series to 50 Ohm load. The loss through the filter is around 10dB instead of 3dB, the ripple is around 6-8db instead of 1dB. The filter response shows double peaks with dip between, either side of the peaks falls off extremely quickly at around 2 kHz off (should be +/- 15kHz bandwidth). I would appreciate any help I can get to determine what is happening and to correctly match into this filter that requires 800R//3pF terminations at 45 MHz. AndyS wrote: > Andy comments: > > I haven't used that particular dual gate Mosfet, but I will tell you > how I have used 3n140, 3n141, and others: > > G2 was used as the LO and was bias at around 3 volts DC with > resistors. The LO was cap coupled in at a leveL of about 2.5 Vrms. > It is useD as a switching signal to drive the MOSFET into and out > of conduction. It takes very little power from the LO, but the > 2.5 Vrms swing was needed... > > G1 was used as the RF port. G1 and the source were biased > pretty much as you described. > > The drain was similar to your design. While using a 1K resistor > gives > a great source impedance to the xtal filter, it also absorbs most of > the signal.... If I remember, the output Z is 9 or 10 k for the devices > I used. I would use maybe a 7.5 K resistor and then impedance > match in the tuned circuit to get the source right. This usually took > some experimentation. Since the drain output was tuned to a different > frequency than the LO or the RFin, I never had a stability problem. > Power gains of 15 to 20 db were very common... ( Note , I said > POWER gain, and not voltage gain , which could be anything... ) > > > > Maybe my experience is outdated with the newer Mosfets, but I > have never seen, or used a circuit that put the LO on G!.... It was > always on G2.. I used dual gate mosfets to build receiver front > ends and mixer from about 1967 to about 1990. Then I started > using doubly balanced stuff like SBLs and MDs ..... I followed them > with a nice amplifer and good termination.....It costs a little more, > but the designs were always more stable and gave better > performance..... > > I hope this helps. Perhaps others here have used your particular > device and can give better guidance... > > Andy W4OAH > Article: 97815 of rec.radio.amateur.homebrew From: nospam@nouce.bellatlantic.net Subject: Re: Help with Mosfet mixer Message-ID: References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> Date: Sun, 02 Jul 2006 23:01:36 GMT On Sun, 02 Jul 2006 22:45:57 GMT, David wrote: Since everyone is top posting. Having G2 driven hard is good for large signal handling as mixing will occure with lesser levels. So that's why that needs to be done. If driven hard enough bias has no effect. I vaugely remember you saying your using two filters back to back... If so you may have the interfilter coupling way off. Also the loss for two 3db loss filters would be a bit higher than 6db if everything is right. Allison >I noted in We Hayward's book "Experimental Methods in RF Design" that he >suggests the gain of a Dual Gate Mosfet in a mixer circuit is about 1/4 >of the gain of the same device in an RF amp circuit. If this is true >then the 6dB gain I now see in the mixer stage would be about right. > >I cranked up the LO level and now have +/- 4V on G2. I tried biasing the >Gate up to 3 but it made no difference than when just 47K to ground >bias was used on G2. > >The main issue I am having now is matching to the 4-pole filter. >I have tried several approaches and the performance is disgusting. > >The current mixer to filter circuit is.... > >This "should" have matched down to 800R > >100nH (Q=100) inductor to Vcc from Drain >6-30p trimmer to ground from drain >Split capacitor tap from drain to ground (220pF in series with 200pF) > >1st filter, 4p7 to ground between 1st and second filter. > >Output match to 50R from 800R for testing... >100nH to ground from filter output >82pF to ground >6-30p trimmer to ground >15pF in series to 50 Ohm load. > >The loss through the filter is around 10dB instead of 3dB, the ripple is >around 6-8db instead of 1dB. The filter response shows double peaks with > dip between, either side of the peaks falls off extremely quickly at >around 2 kHz off (should be +/- 15kHz bandwidth). > >I would appreciate any help I can get to determine what is happening and >to correctly match into this filter that requires 800R//3pF terminations >at 45 MHz. > > >AndyS wrote: >> Andy comments: >> >> I haven't used that particular dual gate Mosfet, but I will tell you >> how I have used 3n140, 3n141, and others: >> >> G2 was used as the LO and was bias at around 3 volts DC with >> resistors. The LO was cap coupled in at a leveL of about 2.5 Vrms. >> It is useD as a switching signal to drive the MOSFET into and out >> of conduction. It takes very little power from the LO, but the >> 2.5 Vrms swing was needed... >> >> G1 was used as the RF port. G1 and the source were biased >> pretty much as you described. >> >> The drain was similar to your design. While using a 1K resistor >> gives >> a great source impedance to the xtal filter, it also absorbs most of >> the signal.... If I remember, the output Z is 9 or 10 k for the devices >> I used. I would use maybe a 7.5 K resistor and then impedance >> match in the tuned circuit to get the source right. This usually took >> some experimentation. Since the drain output was tuned to a different >> frequency than the LO or the RFin, I never had a stability problem. >> Power gains of 15 to 20 db were very common... ( Note , I said >> POWER gain, and not voltage gain , which could be anything... ) >> >> >> >> Maybe my experience is outdated with the newer Mosfets, but I >> have never seen, or used a circuit that put the LO on G!.... It was >> always on G2.. I used dual gate mosfets to build receiver front >> ends and mixer from about 1967 to about 1990. Then I started >> using doubly balanced stuff like SBLs and MDs ..... I followed them >> with a nice amplifer and good termination.....It costs a little more, >> but the designs were always more stable and gave better >> performance..... >> >> I hope this helps. Perhaps others here have used your particular >> device and can give better guidance... >> >> Andy W4OAH >> Article: 97816 of rec.radio.amateur.homebrew From: David Subject: Re: Help with Mosfet mixer References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> <1151883087.766705.136330@v61g2000cwv.googlegroups.com> Message-ID: Date: Mon, 03 Jul 2006 00:02:52 GMT Andy, The input to the mixer on G1 is the second stage of a DTC. The DTC was designed to provide the appropriate RP for a 6MHz bandwidth. I then assumed that G1 will be extremely high impedance compared to the DTC and therefore would not load it down. The gain was measured by first measuring the power output of the mixer and then measuring the power output at the end of the filter. The manufacturer data for the filter specifies maximum loss of 3dB (they supply 2 matches filters that connect to form a 4-pole). The output of the filter was stepped down to 50 Ohms with a C-Tap impedance transform on the tuned circuit. The input was matched from 2800 Ohms (Rp of the coil in the mixer tank) to 800 R using a C-Tap transform also. I have since constructed a stand alone filter test jig for the filter only with match on input from 50 Ohms up to 800 and 800 back to 50. I calibrate the output level with bypass across filter first for reference level on the spectrum analyzer and then include the filter in the path. With this method I measure 4.8 dB loss and the double peaking action has gone. The 1dB bandwidth was measured at +/- 9kHz. When I sweep across the required bandwidth (+/-15kHz) I get 2.8dB loss at the low end and 7.5dB at the high end (relative to the centre peak). The tuning caps are able to peak the circuit without being turned to max or min c, so I expect the tuned circuits are resonating ok. Regards David AndyS wrote: > David wrote: >> I noted in We Hayward's book "Experimental Methods in RF Design" that he >> suggests the gain of a Dual Gate Mosfet in a mixer circuit is about 1/4 >> of the gain of the same device in an RF amp circuit. If this is true >> then the 6dB gain I now see in the mixer stage would be about right. >> >> I cranked up the LO level and now have +/- 4V on G2. I tried biasing the >> Gate up to 3 but it made no difference than when just 47K to ground >> bias was used on G2. >> >> The main issue I am having now is matching to the 4-pole filter. >> I have tried several approaches and the performance is disgusting. >> >> The current mixer to filter circuit is.... >> >> This "should" have matched down to 800R >> >> 100nH (Q=100) inductor to Vcc from Drain >> 6-30p trimmer to ground from drain >> Split capacitor tap from drain to ground (220pF in series with 200pF) >> >> 1st filter, 4p7 to ground between 1st and second filter. >> >> Output match to 50R from 800R for testing... >> 100nH to ground from filter output >> 82pF to ground >> 6-30p trimmer to ground >> 15pF in series to 50 Ohm load. >> >> The loss through the filter is around 10dB instead of 3dB, the ripple is >> around 6-8db instead of 1dB. The filter response shows double peaks with >> dip between, either side of the peaks falls off extremely quickly at >> around 2 kHz off (should be +/- 15kHz bandwidth). >> >> I would appreciate any help I can get to determine what is happening and >> to correctly match into this filter that requires 800R//3pF terminations >> at 45 MHz. >> >> > Andy writes: > > Ok. Well, using +/- 4 volts ( i am guessing rms) will certainly > drive > the mosfet from full on to cutoff so DC biasing wouldn't be required. > Less LO could be used with a DC bias, but if you have the LO power > available, there is no reason to change. > > I am assuming that you have gotten rid of the 800 drain load..... > The split cap approach is fine and should give you about a 4/1 > step down, so if the drain output imp is 3200 ohms or thereabout, the > match should be close... ( I am doing this in my head, so forgive me if > > I am off by a thousandfold :>))) ) > > Now, the filter loss is something else. You did not tell me how you > > measured it, and I am assuming that you just measured the voltages > and used that. This is a common mistake as there can be substantial > impedance change. The only accurate way to characterize filter loss > is with a special test jig which can measure the power into the load > without the filter and then the power into the load WITH the filter, > without > changing any of the tuning.... A purely resistive jig with a highZ > probe > can be fairly accurate, measuring voltage loss..... But you have to > allow > for any impedance changes in source and load....... > > The inter match between the two filters should have both and L and > a C > making a parallel tank to make sure both the filter reactance, and the > stray reactances are tuned out. Usually filters are slightly > capacitive > , a couple pf, on their parallel terminal impedance......a tuned > circuit > will tune all this out..... giving you 800 to 800... You tune the tank > for minimum ripple in the passband... not for max gain at one of > the ripples.... tho it will be close... > > The output transformation from 50 ohms up to 800 ohms represents > a 4 to 1 voltage transformation, or 12 db voltage loss..... In other > words, > if you used an 800 ohm resistive load (with a parallel tank to get rid > of the reactance and strays) you would, with a voltage probe, measure > 12 db higher than you would when you transformed the load down to > 50 ohms.... If you already knew this, and accounted for it, I > apologize for > assuming you didn't,, , but it is a common mistake some people have > made.... > > I don't disagree with Wes's book or explanation at all, but I am > surprised > that 12 db was the best the mosfet would do.....but, as I said, I have > never > used that particular one... > > Remember, you have to match the RF generator UP to the input > Z of G1 in order to calculate the conversion gain. If you have just > connected G1 to a 50 ohm RF source, you are losing a lot of voltage > since the input Z of G! is probably a couple K..... That is quite a > voltage gain.... and that is before the conversion process even > starts.... > > It looks to me like you are on the right track. Again , I apologize > if it seemed > I was "talking down" to you, but I am just doing an all-purpose memory > dump > of all I remember about when I did this..... And I know for sure that > > I got a hell of a lot more conversion gain out of a 3n141..... after > matching > both the input to G1 AND the output to a matched load.... > > Goodluck,, > > Andy W4OAH > Article: 97817 of rec.radio.amateur.homebrew From: David Subject: Re: Help with Mosfet mixer References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> <1151883087.766705.136330@v61g2000cwv.googlegroups.com> Message-ID: Date: Mon, 03 Jul 2006 02:01:56 GMT Andy, I realise when I re-read your post that I have not included the loss of the tuned circuit each side of the filter due to Rp of the inductors. Taking this into account, the max. loss should be around 1.1dB per tuned circuit + 3dB max. for filter = 5.2dB. I re-measured the response using the digital power meter as this is more accurate than the spectrum analyser relative measurements. The insertion loss of filter AND tuned circuits was measured at 3.7dB I then swept the filter and measured the -3dB bandwidth and found this to be -18kHz, + 15.5kHz (very close to the expected +/- 15 kHz). Next I measured stop band attenuation at +/- 60kHz and measured -47.3 dB on low side and -50.7 dB on high side (manufacture data was for at least 40dB). I then looked at ripple in the pass band. There was 1 ripple that produces a dip at +9kHz of 1.6dB and a slight peak at +13 kHz of 0.86dB. This is very close to the 1dB figure mentioned in the datasheet. There was no ripple below Fo. If I can now get the impedance transformation in my circuit working the same as this then I'm on my way. I'll leave the output match as-is and if there are issues then it eliminates the output load and just leaves work to do at the mixer end. This is the first discrete mixer and crystal filter I have constructed. I'm not sure if I am overlooking anything here but to me those figures now look good. Does this all sound reasonable ? Thanks heaps Regards David AndyS wrote: > David wrote: >> I noted in We Hayward's book "Experimental Methods in RF Design" that he >> suggests the gain of a Dual Gate Mosfet in a mixer circuit is about 1/4 >> of the gain of the same device in an RF amp circuit. If this is true >> then the 6dB gain I now see in the mixer stage would be about right. >> >> I cranked up the LO level and now have +/- 4V on G2. I tried biasing the >> Gate up to 3 but it made no difference than when just 47K to ground >> bias was used on G2. >> >> The main issue I am having now is matching to the 4-pole filter. >> I have tried several approaches and the performance is disgusting. >> >> The current mixer to filter circuit is.... >> >> This "should" have matched down to 800R >> >> 100nH (Q=100) inductor to Vcc from Drain >> 6-30p trimmer to ground from drain >> Split capacitor tap from drain to ground (220pF in series with 200pF) >> >> 1st filter, 4p7 to ground between 1st and second filter. >> >> Output match to 50R from 800R for testing... >> 100nH to ground from filter output >> 82pF to ground >> 6-30p trimmer to ground >> 15pF in series to 50 Ohm load. >> >> The loss through the filter is around 10dB instead of 3dB, the ripple is >> around 6-8db instead of 1dB. The filter response shows double peaks with >> dip between, either side of the peaks falls off extremely quickly at >> around 2 kHz off (should be +/- 15kHz bandwidth). >> >> I would appreciate any help I can get to determine what is happening and >> to correctly match into this filter that requires 800R//3pF terminations >> at 45 MHz. >> >> > Andy writes: > > Ok. Well, using +/- 4 volts ( i am guessing rms) will certainly > drive > the mosfet from full on to cutoff so DC biasing wouldn't be required. > Less LO could be used with a DC bias, but if you have the LO power > available, there is no reason to change. > > I am assuming that you have gotten rid of the 800 drain load..... > The split cap approach is fine and should give you about a 4/1 > step down, so if the drain output imp is 3200 ohms or thereabout, the > match should be close... ( I am doing this in my head, so forgive me if > > I am off by a thousandfold :>))) ) > > Now, the filter loss is something else. You did not tell me how you > > measured it, and I am assuming that you just measured the voltages > and used that. This is a common mistake as there can be substantial > impedance change. The only accurate way to characterize filter loss > is with a special test jig which can measure the power into the load > without the filter and then the power into the load WITH the filter, > without > changing any of the tuning.... A purely resistive jig with a highZ > probe > can be fairly accurate, measuring voltage loss..... But you have to > allow > for any impedance changes in source and load....... > > The inter match between the two filters should have both and L and > a C > making a parallel tank to make sure both the filter reactance, and the > stray reactances are tuned out. Usually filters are slightly > capacitive > , a couple pf, on their parallel terminal impedance......a tuned > circuit > will tune all this out..... giving you 800 to 800... You tune the tank > for minimum ripple in the passband... not for max gain at one of > the ripples.... tho it will be close... > > The output transformation from 50 ohms up to 800 ohms represents > a 4 to 1 voltage transformation, or 12 db voltage loss..... In other > words, > if you used an 800 ohm resistive load (with a parallel tank to get rid > of the reactance and strays) you would, with a voltage probe, measure > 12 db higher than you would when you transformed the load down to > 50 ohms.... If you already knew this, and accounted for it, I > apologize for > assuming you didn't,, , but it is a common mistake some people have > made.... > > I don't disagree with Wes's book or explanation at all, but I am > surprised > that 12 db was the best the mosfet would do.....but, as I said, I have > never > used that particular one... > > Remember, you have to match the RF generator UP to the input > Z of G1 in order to calculate the conversion gain. If you have just > connected G1 to a 50 ohm RF source, you are losing a lot of voltage > since the input Z of G! is probably a couple K..... That is quite a > voltage gain.... and that is before the conversion process even > starts.... > > It looks to me like you are on the right track. Again , I apologize > if it seemed > I was "talking down" to you, but I am just doing an all-purpose memory > dump > of all I remember about when I did this..... And I know for sure that > > I got a hell of a lot more conversion gain out of a 3n141..... after > matching > both the input to G1 AND the output to a matched load.... > > Goodluck,, > > Andy W4OAH > Article: 97818 of rec.radio.amateur.homebrew From: nospam@nouce.bellatlantic.net Subject: Re: Help with Mosfet mixer Message-ID: References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> <1151883087.766705.136330@v61g2000cwv.googlegroups.com> Date: Mon, 03 Jul 2006 02:04:26 GMT On 2 Jul 2006 16:31:27 -0700, "AndyS" wrote: > >David wrote: >> I noted in We Hayward's book "Experimental Methods in RF Design" that he >> suggests the gain of a Dual Gate Mosfet in a mixer circuit is about 1/4 >> of the gain of the same device in an RF amp circuit. If this is true >> then the 6dB gain I now see in the mixer stage would be about right. >> >> I cranked up the LO level and now have +/- 4V on G2. I tried biasing the >> Gate up to 3 but it made no difference than when just 47K to ground >> bias was used on G2. >> >> The main issue I am having now is matching to the 4-pole filter. >> I have tried several approaches and the performance is disgusting. >> >> The current mixer to filter circuit is.... >> >> This "should" have matched down to 800R >> >> 100nH (Q=100) inductor to Vcc from Drain >> 6-30p trimmer to ground from drain >> Split capacitor tap from drain to ground (220pF in series with 200pF) >> >> 1st filter, 4p7 to ground between 1st and second filter. >> >> Output match to 50R from 800R for testing... >> 100nH to ground from filter output >> 82pF to ground >> 6-30p trimmer to ground >> 15pF in series to 50 Ohm load. >> >> The loss through the filter is around 10dB instead of 3dB, the ripple is >> around 6-8db instead of 1dB. The filter response shows double peaks with >> dip between, either side of the peaks falls off extremely quickly at >> around 2 kHz off (should be +/- 15kHz bandwidth). >> >> I would appreciate any help I can get to determine what is happening and >> to correctly match into this filter that requires 800R//3pF terminations >> at 45 MHz. >> >> >Andy writes: > > Ok. Well, using +/- 4 volts ( i am guessing rms) will certainly >drive >the mosfet from full on to cutoff so DC biasing wouldn't be required. >Less LO could be used with a DC bias, but if you have the LO power >available, there is no reason to change. You need to drive it hard for best overload performance. DGfets were a favorite before DBMs and other high level mixers or Gilbert cells. > I am assuming that you have gotten rid of the 800 drain load..... >The split cap approach is fine and should give you about a 4/1 >step down, so if the drain output imp is 3200 ohms or thereabout, the >match should be close... ( I am doing this in my head, so forgive me if > >I am off by a thousandfold :>))) ) You likely right on. I used 5k as a round number years ago with success with 3n203s and the BF998 devices have higher GM and Idss so that would fit with your number. If you load it low the gain drops but overload and noise performance is not hurt badly. > > Now, the filter loss is something else. You did not tell me how you > >measured it, and I am assuming that you just measured the voltages >and used that. This is a common mistake as there can be substantial >impedance change. The only accurate way to characterize filter loss >is with a special test jig which can measure the power into the load >without the filter and then the power into the load WITH the filter, >without >changing any of the tuning.... A purely resistive jig with a highZ >probe >can be fairly accurate, measuring voltage loss..... But you have to >allow >for any impedance changes in source and load....... The other nasty is most of those filters are more sensitive to reactive loading than errors is resistive loading. So the scope probe C (cheap probes can be 7-10pf) can be a real factor in both meaurement error and circuit loading(capacitive termination). > The inter match between the two filters should have both and L and >a C >making a parallel tank to make sure both the filter reactance, and the >stray reactances are tuned out. Usually filters are slightly >capacitive >, a couple pf, on their parallel terminal impedance......a tuned >circuit >will tune all this out..... giving you 800 to 800... You tune the tank >for minimum ripple in the passband... not for max gain at one of >the ripples.... tho it will be close... > > The output transformation from 50 ohms up to 800 ohms represents >a 4 to 1 voltage transformation, or 12 db voltage loss..... In other >words, >if you used an 800 ohm resistive load (with a parallel tank to get rid >of the reactance and strays) you would, with a voltage probe, measure >12 db higher than you would when you transformed the load down to >50 ohms.... If you already knew this, and accounted for it, I >apologize for >assuming you didn't,, , but it is a common mistake some people have >made.... > > I don't disagree with Wes's book or explanation at all, but I am >surprised >that 12 db was the best the mosfet would do.....but, as I said, I have >never used that particular one... The fet is a square law mixer so gain and conversion figures are not the same as if it were straight amplifer. The amplifier form is two cascaded gain stages and the mixer form is an amplifer with a series switch, least that model works for me. > Remember, you have to match the RF generator UP to the input >Z of G1 in order to calculate the conversion gain. If you have just >connected G1 to a 50 ohm RF source, you are losing a lot of voltage >since the input Z of G! is probably a couple K..... That is quite a >voltage gain.... and that is before the conversion process even >starts.... > > It looks to me like you are on the right track. Again , I apologize >if it seemed >I was "talking down" to you, but I am just doing an all-purpose memory >dump >of all I remember about when I did this..... And I know for sure that >I got a hell of a lot more conversion gain out of a 3n141..... after >matching >both the input to G1 AND the output to a matched load.... Big time! I found that the '141 and friends like to see around 1-2k impedence level for best gain and at less than 600 ohms it was pretty poor. Noise figure also improves. Allison > > Goodluck,, > > Andy W4OAH Article: 97819 of rec.radio.amateur.homebrew Date: Sun, 02 Jul 2006 19:47:51 -0700 From: Tim Wescott Subject: Re: Help with Mosfet mixer References: <5bJpg.19786$ap3.8783@news-server.bigpond.net.au> <1151861257.221100.12120@j8g2000cwa.googlegroups.com> <1151883087.766705.136330@v61g2000cwv.googlegroups.com> Message-ID: <3KGdnZh3W_TPGDXZnZ2dnUVZ_vadnZ2d@web-ster.com> David wrote: > Andy, > > The input to the mixer on G1 is the second stage of a DTC. The DTC was > designed to provide the appropriate RP for a 6MHz bandwidth. I then > assumed that G1 will be extremely high impedance compared to the DTC > and therefore would not load it down. > > The gain was measured by first measuring the power output of the mixer > and then measuring the power output at the end of the filter. > > The manufacturer data for the filter specifies maximum loss of 3dB (they > supply 2 matches filters that connect to form a 4-pole). > > The output of the filter was stepped down to 50 Ohms with a C-Tap > impedance transform on the tuned circuit. > > The input was matched from 2800 Ohms (Rp of the coil in the mixer tank) > to 800 R using a C-Tap transform also. > -- snip -- This could be your problem right here -- at 45MHz it's probably not realistic to expect no loss in the mixer drain circuit. I'd find the Q of the mixer tank without the filter, and use that to calculate the effective parallel resistance, as well as the attenuation of the filter. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Posting from Google? See http://cfaj.freeshell.org/google/ "Applied Control Theory for Embedded Systems" came out in April. See details at http://www.wescottdesign.com/actfes/actfes.html Article: 97820 of rec.radio.amateur.homebrew From: Ben Jackson Subject: Re: Self-heating of crystal in inverter oscillator References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Mon, 03 Jul 2006 00:02:31 -0500 On 2006-07-01, nospam@nouce.bellatlantic.net wrote: > On Sat, 01 Jul 2006 02:23:19 -0500, Ben Jackson wrote: > >>> I suggest a discrete Bipolar or FET where you can control the >>> operating point of the device better. >> >>If I can't tame this VCXO I will try that. This must be how Manhattan >>prototyping branches off into "Ugly"... Well, this might be the best advice I ever got from Usenet. I fought every parameter in the 'HC86 inverter oscillator and lost. The fact that it works great at 14.85MHz and the elegance of using up the extra gates lured me in. The whole thing is very voltage sensitive (around 1Hz/mV at the output of the gate, making it very sensitive to Rs as well). This might be due to the propagation parameters of the gate varying substantially with temperature and voltage. I built a Colpitts oscillator with a plain old 2N3904 and it hasn't moved by more than a few Hz in the hour it's been on. Thanks! -- Ben Jackson http://www.ben.com/ Article: 97821 of rec.radio.amateur.homebrew From: "jack" References: <1151911418.539954.235680@v61g2000cwv.googlegroups.com> Subject: Re: Inductance Capacity meter Date: Mon, 3 Jul 2006 18:58:09 -0400 Message-ID: WB9LVI's "LMS" was described in QEX -- ultra simple -- just your sound card and an opamp or so: http://www.arrl.org/qex/2005/Steber.pdf there is a link to the exe file in the PDF. Jack "Paolo IW3ARV" wrote in message news:1151911418.539954.235680@v61g2000cwv.googlegroups.com... > Hello, > > anyone can suggest a schematics of a simple analog inductance/capacity > meter. > > Thanks Paolo Iw3arv > Article: 97822 of rec.radio.amateur.homebrew From: "Mike Andrews" Subject: Re: IEEE Standard for RF Safety Levels Date: Mon, 3 Jul 2006 14:02:54 +0000 (UTC) Message-ID: References: <1151772940.769643.43270@v61g2000cwv.googlegroups.com> <1151801703.859338.130820@j8g2000cwa.googlegroups.com> <1151880587.942126.226120@a14g2000cwb.googlegroups.com> Dr. Jeff wrote: > I'm not so much worried about hazardous effects, it's just that I don't > think the cable company should be installing equipment 50 feet from my > home that is broadcasting RF > so close to the 80 meter band! I'm also tired of doing "their job" for > them: last year when the neighborhood experienced problems for weeks > and weeks with their Internet system, I had to show their field > engineer that there was a problem on the "uplink" side of their > network. "By golly gee, you're right!" was the prognosis from the back > of the Cable truck.... You're so right about not doing their job for them, and even more so about them leaking interfering signals. I've got used to being the first in the area to report problems with the cable: I depend on the 'Net link being _UP_, and know (from my dayjob) how to do problem determination and tracing. You get to be the first to report their problem with something leaking around 4 MHz., and to press the issue with your city management (if they're city-franchised, as so many cablecos are) and up the line to the FCC if the cableco and the franchisor are unresponsive. Do please keep us posted. -- Mike Andrews, W5EGO mikea@mikea.ath.cx Tired old sysadmin Article: 97823 of rec.radio.amateur.homebrew From: "Pete KE9OA" References: <9c0u7e.qnd.ln@tg6124.ab0wr.net> <1uudnfjaxZcAkjjZnZ2dnUVZ_vWdnZ2d@comcast.com> Subject: Re: Spurs on mixer output Date: Mon, 3 Jul 2006 16:56:44 -0500 Message-ID: I figured something like that occured. Sometimes, I even receive direct e-mails from group postings. No offense intended. Pete wrote in message news:ftaea2tcnvusccfhks3o5g72t6qkr6u7p1@4ax.com... > > Not to belabor but as explanation. I use Free Agent and it displays > in indented threaded form so your reply was nested two deep from > my first reply posting. > > Allison > Kb1GMX > > On Sat, 1 Jul 2006 14:50:17 -0500, "Pete KE9OA" > wrote: > >>This thread is directed at the author, not you. The purpose of my posting >>in >>the latest position of the thread is to move things in a chronological >>order. The original poster knows how to read, so it is quite possible that >>this person won't miss my posting. >> >>Pete >> >> wrote in message >>news:r77ba2dqivor2ss3msqp48u3lqm3962r76@4ax.com... >>> On Fri, 30 Jun 2006 06:48:45 -0500, "Pete KE9OA" >>> wrote: >>> >>>>What kind of spectrum analyzer are you using? What are the front end >>> >>> I'm not using one the author of the thread is. >>> >>>>attenuator settings on the spectrum analyzer? What is your reference >>>>level? >>> >>> Ask him not me. >>> >>>>All of these things, especially the front end attenuator settings, can >>>>affect your result. If the 1st mixer in the spectrum analyzer is driven >>>>into >>>>nonlinearity, you can see all kinds of IMD products that are generated >>>>in >>>>the analyzer itself. >>>>Also, why are you doing this test with the RF port of the mixer >>>>terminated >>>>in 50 Ohms? This type of termination is only used when doing either >>>>return >>>>loss tests or noise balance tests. >>>>If you are driving the SBL-1 mixer with +7 to +9dBm of LO level and you >>>>are >>>>driving the RF port with a signal that is at least 20dB below the 1dB >>>>compression point of the SBL-1, the main things you should see at the >>>>I.F. >>>>port are a supressed LO signal, an upper sideband that is about 7dB >>>>lower >>>>in >>>>level than the RF injection level, and a lower sideband that is also >>>>about >>>>7dB lower in level than the RF injection level. >>>>The 1dB compression point on the SBL-1 is about 0dBm, so I would set the >>>>level to the RF port at -20dBm. If you go above this level, you will see >>>>higher conversion loss, and possibly more IMD products at the I.F. port >>>>of >>>>the mixer. >>>>In conclusion, make sure that the IMD isn't being generated in your test >>>>setup, and make sure that you are not exceeding the recommended RF input >>>>level to the SBL-1. >>>> >>>>Pete >>> >>> You top posted to a reply that I'd posted to and your context is way >>> off as a result. Go bat to the root of the thread and read the >>> posting again. >>> >>> Briefly, he's seeing spurs every 25 or 50 khz with a LO in the 45mhz >>> region and NO RF on the input (unterminated RF port). >>> >>> Allison >>> >>> >>>> >>>> wrote in message >>>>news:p9o5a21152qsldg22fqccf0tm1ba7grf2d@4ax.com... >>>>> On Wed, 28 Jun 2006 07:43:20 -0500, tim gorman >>>>> wrote: >>>>> >>>>>>john wilkinson wrote: >>>>>> >>>>>>> >>>>>>> >>>>>>> Hi, >>>>>>> If I feed my second mixer into a spectrum analyser, and inject a >>>>>>> 44.545MHz >>>>>>> LO, with no power to the first IF stage, I see spurs at about >>>>>>> 48-50KHz >>>>>>> intervals on the mixer output, from 0 to the 455KHz normal output >>>>>>> freq. >>>>> >>>>>> >>>>>>> The mixer is an SBL-1. >>>>>>> >>>>>>> Any ideas as to where these are comming from? >>>>>>> >>>>>>> Best regards, >>>>>>> John >>>>>> >>>>>>A couple of observations. >>>>>> >>>>>>If you simply disconnected the second mixer from the 1st mixer then it >>>>>>sounds like you do not have the output of the 1st mixer properly >>>>>>terminated. Unless, that is, the spectrum analyzer provides a good >>>>>>50ohm >>>>>>termination in the probe. The SBL-1 is a double-balanced mixer but in >>>>>>order >>>>>>to get the "balance" to work right you must properly terminate *all* >>>>>>ports. >>>>>>Otherwise all kinds of impedances can be "thrown" back to the other >>>>>>ports - >>>>>>causing all kinds of problems with attached LO's and RF stages. >>>>>> >>>>>>Regularly spaced spurs from DC to 455khz does not sound like spurious >>>>>>mixing >>>>>>products. It sounds more like an oscillator being driven into >>>>>>saturation >>>>>>causing square waves to be produced which are providing regular >>>>>>harmonic >>>>>>outputs. This could be a product of poor terminations on the mixer >>>>>>ports. >>>>> >>>>> Tim, the LO is 45.455 (or 44.545) either way there should be no LF >>>>> outputs from the mixer below the LO injection unless it's a spur on >>>>> the LO. >>>>> >>>>>>Directly connecting the output of a SBL-1 to the input of another >>>>>>mixer, >>>>>>even another SBL-1, is not recommended either. The SBL-1 does not have >>>>>>built-in terminations. A good, symmetric, 50ohm 3db pad between the >>>>>>stages >>>>>>would provide a much better setup and would not significantly impact >>>>>>your >>>>>>overall noise factor. Be sure and connect your spectrum analyzer to >>>>>>the >>>>>>far >>>>>>side of the pad. >>>>> >>>>> Thats true though his testing is with a 20db IF after it and one would >>>>> hope that does present a 50ohm match to the IF port. Usually if the >>>>> poarts are badly matched the mixing spurs are greater and the port >>>>> to port isolation go to pot. If the only thing going in is the LO >>>>> then likely the LO is the source but if there is gain flollowing then >>>>> the gain stage is also suspect. >>>>> >>>>> I've worked with enough SBL1 and MD108s and all their similar DBMS >>>>> to know the SBL1 in this case is not the offendor Even if >>>>> misterminated. Likely causes are the 45mhz filter is looking reactive >>>>> to the IF amp and the IF is unstable (makes a fine OSC) or there is >>>>> some other source of RF that is unaccounted for (spurs). >>>>> >>>>> >>>>> Allison >>>>> Kb!GMX >>>> >>> >> > Article: 97824 of rec.radio.amateur.homebrew From: "Kirk" Subject: frequency meter Date: 3 Jul 2006 18:27:32 -0700 Message-ID: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> I have looked at used eqpt etc and kits. Most kits are partial kits. How I wish Heath were still in business :( Any recommendations for a frequency meter of good accuracy. I dont need high frequency capability - a few MHz is good enough but I need good accuracy. thanks Kirk KC7THL Article: 97825 of rec.radio.amateur.homebrew From: fmmck@aol.com (Fred McKenzie) Subject: Re: frequency meter Date: Mon, 03 Jul 2006 23:30:52 -0400 Message-ID: References: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> In article <1151976452.561672.72470@j8g2000cwa.googlegroups.com>, "Kirk" wrote: > I have looked at used eqpt etc and kits. Most kits are partial kits. > How I wish Heath were still in business :( > > Any recommendations for a frequency meter of good accuracy. I dont need > high frequency capability - a few MHz is good enough but I need good > accuracy. Kirk- Believe it or not, Heath did not go out of business. They just stopped selling Heathkits! How accurate is accurate? If one part per million is acceptable, many counters will do that. If your requirement is better than that, look for a counter with an oven-controlled crystal oscillator. If that still isn't good enough, you may be able to obtain a Rubidium-controlled oscillator (or GPS-controlled) to use as an external timebase. If you are willing to spend the money, look at Agilent (HP) and Phillips (Fluke) as sources. If you're looking for a bargain, then there are several HP and Fluke counters that show up on eBay that should meet your needs. Examples are Fluke's 7220A, 7260A and 7261A. One of these with the high-accuracy option might sell for around $75. Another good one is the HP 5328, also available with the high-stability option. I think this is the one that shows up in a military configuration that includes the high-stability oscillator as well as a 500 MHz pre-scaler. Fred K4DII Article: 97826 of rec.radio.amateur.homebrew From: "Reg Edwards" References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Subject: Re: How to calculate increase of home wireless router range? Date: Tue, 4 Jul 2006 07:42:40 +0100 Message-ID: "Beverly Erlebacher" wrote in message news:2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net... > Can you help me roughly CALCULATE how to increase the range of my home > Internet wireless WiFi setup to a shed 300 feet away from my house? > > Presently, I can walk about half the way through the wooded area to the > shed with my laptop in hand before I lose the connection to the PCMCIA > 802.11b,g Linksys card. Basically I need to gain 150 feet in "range". > > But how? > > At the store, I immediately become confused as I try to compare $30 USD > omnidirectional antennas (D-Link ANT24-070) that boost "power" by a claimed > 7 db; $50 USD directional corner antennas (Hawking HAI15SC) that claim 15 > dbi (whatever a dBi is); and $150 USD 802.11N routers that claim to boost > omnidirectional "range" by 4x (Linksys WRT300N). > > How does an omnidirectional 7 db or directional 15 dBi boost in "power" > equate to range? > > Approximately how many decibels of (omnidirectional or directional) power > do I really need to boost my WiFi range from about 150 feet to the 300 feet > I need? > > Looking up what a decibel is > (http://en.wikipedia.org/wiki/Decibel#Definition), I > calculate the D-Link ANT24-070 omnidirectional antenna gives me about 5 > times the power (assuming 7 db = 10^7/10 ~= 5); but does this get me the > additional 150 feet of range to my shed? > > Spending almost twice as much money on the Hawking HAI15SC directional > antenna gets me roughly 30 times the power (assuming 15 db = 10^15/10 ~= > 32); but is that enough power to get me the range to my shed? > > Indeed, is there some way to add a Hawking 15db antenna on the receiving > end to get 1,000 times the power (15 db + 15 db = 30 db = 10^30/10 ~= > 1,000); but what would I hook the wire output from this receiving antenna > to in the shed (I can't hook it to the pcmcia card, can I)? > > Given those db calculations, how do I compare the antenna options with > replacing my home 802.11b,g router with the 4X range $150 USD Linksys > 802.11n WRT300N router and the required $120 USD Linksys WPC300N PCMCIA > card (assuming 6 db = 10^6/10)?Will this three-antenna 802.11n router be > forced to drop down to 1X speeds because inside my house my kid's laptops > will all be using 802.11b or 802.11g? Or can the router work on both > 802.11g to one computer and on 802.11n to the other computer at the same > time? > > I'm so confused! > > All I want is to make a well-informed buying decision to increase my WiFi > range reliably to 300 feet to a known point. > > Can you help me sort out all these very confusing variable (to me anyway)? > I have no training in electrical engineering; but I can google. > > Thank you, > Beverly ========================================== Very simply - four times the transmitter power ( +6 dB ) doubles the range. Is your receiver sufficiently sensitive? Or is the received signal below the noise level? ---- Reg. Article: 97827 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: Date: Tue, 04 Jul 2006 06:49:19 GMT On Tue, 04 Jul 2006 06:28:16 -0000, Dave Platt wrote: >>Can you help me roughly CALCULATE how to increase the range of my home >>Internet wireless WiFi setup from 150 feet to a shed 300 feet away? > Doubling the range requires 6 dB of additional gain from the antennas > at one end or the other. Hi Dave, First thank you for taking the time to help me and anyone who read this. Second, I'm going to have to go slowly with you so I'll respond one by one. Third, does your statement that 6 dB of gain equates to 2 times the range mean that the "square root" of the power difference is my key to calculating the range? That is, is this range calculation from dB power roughly true (based on what you said)? 6 dB = 10^(6/10) ~= 4X the power, where the square root of 4X equals a doubling the range (assuming an omnidirectional antenna)? Beverly Article: 97828 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: Date: Tue, 04 Jul 2006 07:22:44 GMT > 6 dB = 10^(6/10) ~= 4X the power, where the square root of 4X equals a > doubling the range (assuming an omnidirectional antenna)? I'm hoping I can extrapolate from the above statement to calculate the dB gain for the $150 Linksys WRT300N router which claims a 4X range improvement (so I can compare the $50 antenna's effect with that of the 802.11n router). Following your lead, the power improvement necessary for a 4X range improvement is 4^2 = 16X power gain. This 16X power gain then equates to about 12 dB (since 12 dB = 10^[12/10] ~= 16X power). So, is it safe to calculate that the claimed 4X range improvement of the Linksys WRT300N wireless broadband router can be compared to that of a 12 dB gain omnidirectional antenna? Beverly Article: 97829 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: <1aea0pztwz017$.67s063ytjufg.dlg@40tude.net> Date: Tue, 04 Jul 2006 07:36:53 GMT On Tue, 04 Jul 2006 06:28:16 -0000, Dave Platt wrote: >>Can you help me roughly CALCULATE how to increase the range of my home >>Internet wireless WiFi setup to a shed 300 feet away from my house? > > dBi refers to gain relative to an "isotropic" antenna > dBd refers to gain relative to a half-wave dipole > dBi numbers are approximately 2 dB higher than dBd numbers, > for the same actual amount of gain. Hi Dave, Oh my. I guess the Hawking marketing folks were trying to trick me by quoting a decibel number that was higher those I compared with. 15 dBi ~= 15 -2 ~= 13 dBd That makes the $50 USD 15 dBi Hawking HAI15SC Hi_Gain Antenna drop down >from a gain of 32X power to only 20X power which gives me about a 4X range. 13 dBd = 10^(13/10) power ~= 20x power Assuming the square of the power is the range, I get 4X range. 20^(1/2) ~= 4X range Assuming my reliable range is 100 feet, that equates to 400 feet of range. 100 feet * 4 = 400 feet range Interestingly, for comparison purposes, that is the SAME RANGE that the much more expensive Linksys (Cisco) WRT300N router claims. Do these calculations make sense? Beverly Article: 97830 of rec.radio.amateur.homebrew From: MAc Subject: quadrature detector & SSB Date: Tue, 04 Jul 2006 09:45:57 +0200 Message-ID: How to use quadrature detector to demodulate cw and ssb. I want to use AD607 in simple project. There is Quadrature detector on "the end" with two outputs I&Q - and internal phase shifter. How to detest SSB simplest way? 73 mac Article: 97831 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: <8gaum8k8ji29$.1iy8idw960gcu.dlg@40tude.net> Date: Tue, 04 Jul 2006 07:48:38 GMT On Tue, 04 Jul 2006 06:28:16 -0000, Dave Platt wrote: >>Can you help me roughly CALCULATE how to increase the range of my home >>Internet wireless WiFi setup to a shed 300 feet away from my house? > 3 dB of additional gain equates to twice the delivered power at a > specific range. Because power falls off in proportion to the square > of the distance, twice the power yields sqrt(2) or about 1.4 times the > range, all else being equal (which it often isn't). > > 6 dB of additional gain is four times the delivered power at a given > distance, or twice the range for the same amount of power. So that I may compare the different options available at the store to me for increasing my range, are these simplified calculations below correct? a. 3 dBd additional gain = 10^(3/10) ~= 2x the delivered power b. 2x power = 2^(1/2) effective range ~= 1.4X the range b. 6 dBd additional gain = 10^(6/10) ~= 4x the delivered power b. 4x power = 4^(1/2) effective range ~= 2X the range Can someone let me know if these calculations are correct because that helps me equate the different antennas and routers to the one measure I desire, which is effective range in the area of 400 feet. Beverly Article: 97832 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: Date: Tue, 04 Jul 2006 07:53:30 GMT On Tue, 04 Jul 2006 06:28:16 -0000, Dave Platt wrote: >> Approximately how many decibels of (omnidirectional or directional) >> power do I really need to boost my WiFi range from about 150 feet >> to the 300 feet I need? > > The _minimum_ you appear to need is 6 dB of additional gain. I'd > recommend trying for 10 dB or more in order to ensure a reliable > connection. May I ask WHERE that 6 dBd of gain is coming from? Is it ONLY from the "better" antenna? If that additional 6 dBd is coming from a "better" antenna, then why didn't they put that better antenna on my router in the first place? Since the antenna isn't "powerered", there is no external amplifier .... so I am a bit confused as to WHERE that power is coming from? Can you unconfusify me here? Beverly Article: 97833 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> Message-ID: <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> Date: Tue, 04 Jul 2006 08:48:09 GMT On Tue, 04 Jul 2006 06:28:16 -0000, Dave Platt wrote: > It's possible to fabricate a corner reflector, or (even better) a > parabolic reflector, out of material as inexpensive as cardboard > (or posterboard or something like that) lined with aluminum foil. Hmm. At first, I thought you were pulling my leg; but a simple google for more details gave me more homemade WiFi antenna reading than I can handle in a month. Whew. Here, for others to share, are the Yagi pringles can antennas (aka cantenna) which purport to "refocus" the WiFi signal from my router in my house to my shed 300 feet away. http://en.wikipedia.org/wiki/Cantenna http://www.oreillynet.com/cs/weblog/view/wlg/448 http://www.seattlewireless.net/index.cgi/PringlesCantenna http://www.wi-fiplanet.com/reviews/article.php/3401501 http://www.turnpoint.net/wireless/has.html http://www.binarywolf.com/249/pringles_cantenna.htm http://verma.sfsu.edu/users/wireless/pringles.php http://www.seattlewireless.net/index.cgi/CookieCantenna http://webserver.computoredge.com/editorial/2339/cover.htm http://www.signonsandiego.com/news/computing/personaltech/20050613-9999-lz1b13canned.html http://www.overclock.net/faqs/17669-how-make-pringles-can-signal-booster.html http://www.g4tv.com/screensavers/features/40546/Pringles_Can_WiFi_Antenna.html http://www.netscum.com/~clapp/wireless.html http://www.flickr.com/photos/binarywolf/sets/837698/ http://linuxathome.com/files_images/cantenna.pdf Given that there are two fundamental design styles: a) Parabola b) Tube Do folks here recommend the pringles cantenna or the pie tin antenna for my 2-antenna router 802.11b,g directional application where I need to also feed the computers within the house in addition to the shed 300 feet away? Beverly Article: 97834 of rec.radio.amateur.homebrew From: Ben Jackson Subject: Re: quadrature detector & SSB References: Message-ID: Date: Tue, 04 Jul 2006 04:52:53 -0500 On 2006-07-04, MAc wrote: > How to use quadrature detector to demodulate cw and ssb. I want to use > AD607 in simple project. There is Quadrature detector on "the end" with > two outputs I&Q - and internal phase shifter. How to detest SSB simplest > way? If it does all that, you just have to choose USB, LSB or AM by chosing sum, difference or magnitude of the IQ output. -- Ben Jackson http://www.ben.com/ Article: 97835 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> Message-ID: <1i8d1tcl66zdn$.7knr5ebizk69.dlg@40tude.net> Date: Tue, 04 Jul 2006 10:07:11 GMT On Tue, 04 Jul 2006 05:50:02 -0400, Rôgêr wrote: >> Do folks here recommend the pringles cantenna or the pie tin antenna for my >> 2-antenna router 802.11b,g directional application where I need to also >> feed the computers within the house in addition to the shed 300 feet away? > > I use panel antennas almost exclusively, exceptions being some 24dbi > mesh antennas for backhaul. Hi Rôgêr, After reading all the articles posted, I now understand that: a) The pringles can is hip; but it's the worst performer http://www.oreillynet.com/cs/weblog/view/wlg/448 (it's not even metal foil lined and it's too small in diameter) b) The coffee cantenna is more effective than the pringles cantenna http://www.oreillynet.com/cs/user/view/wlg/1124 c) The dish antenna is the simplest of all and almost as good http://www.freeantennas.com/projects/template http://www.freeantennas.com/projects/template2/index.html I also see, as Rod Speed so kindly noted, that the give and take is that we lose range in some directions in favor of range in the desired direction. Fair enough. My one question is a practical one. Why are there two antennas on my router anyway? Is one transmit and the other receive? Or are they both transmit and receive? Given I have TWO omnidirectional antennas on my wireless router, if I put the parabolic dish antenna on one to direct it to my shed, does that allow the OTHER antenna to radiate around the house to handle the other computers roving around the house? Beverly Article: 97836 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Tue, 04 Jul 2006 12:14:00 +0200 Message-ID: References: Ben Jackson napisa³(a): > On 2006-07-04, MAc wrote: >> How to use quadrature detector to demodulate cw and ssb. I want to use >> AD607 in simple project. There is Quadrature detector on "the end" with >> two outputs I&Q - and internal phase shifter. How to detest SSB simplest >> way? > > If it does all that, you just have to choose USB, LSB or AM by chosing > sum, difference or magnitude of the IQ output. > Thank you what frequency should be for Local oscilator? MAc Article: 97837 of rec.radio.amateur.homebrew Date: Tue, 04 Jul 2006 12:21:32 +0100 From: Highland Ham Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Message-ID: Beverly Erlebacher wrote: > Can you help me roughly CALCULATE how to increase the range of my home > Internet wireless WiFi setup to a shed 300 feet away from my house? > > Presently, I can walk about half the way through the wooded area to the > shed with my laptop in hand before I lose the connection to the PCMCIA > 802.11b,g Linksys card. Basically I need to gain 150 feet in "range". > > But how? ==================================== Having followed today's postings on this topic , I see that there is a wooded area between your house and shed, hence there seems to be no free line of sight between the house and the shed. That's why it is difficult to calculate/predict the Gain you need to penetrate the wooded area with a 2.4 GHz signal. If you wish to use the laptop inside the shed at a fixed location it MIGHT be good enough if you install (for example)a corner reflector yagi (High Gain)antenna at both the house AND the shed. However then your laptop needs a plug-in PCMCIA WiFi tansceiver with a connection for an external antenna. One of such units is the Make: Buffalo - Air Station Turbo G ,High Power -unit which also has a built-in antenna. Note : The coaxial cable between the 2 devices and their associated antenna should be limited to only a few metres because of the high frequency being 2.4GHz Communication here is 2 way . Your laptop might receive the ( antenna amplified) signal from your router located in the house ,but that does not mean the router will receive the signal from the laptop without additional facilities at the laptop. Again , because of the probably partly obstructed path (wooded area) it is difficult making any sensible calculations. Frank GM0CSZ / KN6WH Article: 97838 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Tue, 04 Jul 2006 13:55:40 +0200 Message-ID: References: Ben Jackson napisa³(a): > On 2006-07-04, MAc wrote: >> How to use quadrature detector to demodulate cw and ssb. I want to use >> AD607 in simple project. There is Quadrature detector on "the end" with >> two outputs I&Q - and internal phase shifter. How to detest SSB simplest >> way? > > If it does all that, you just have to choose USB, LSB or AM by chosing > sum, difference or magnitude of the IQ output. > What is the signal on "I" output - other way what I will have on "I" output when I put 9MHz on Input and BFO on LO input. Article: 97839 of rec.radio.amateur.homebrew From: "xpyttl" References: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> Subject: Re: frequency meter Message-ID: <_Zsqg.282$Ak3.217@fe04.lga> Date: Tue, 4 Jul 2006 08:15:24 -0400 If you aren't afraid of picking up a soldering iron, it is pretty cheap and easy to build a counter. Counters count -- really --, so precision is completely dependent on how long you are willing to wait. 1 second = 1 Hz, 10 seconds = 0.1 Hz. Counters up to about 60 MHz can be built for under $15. (Well, OK, if your junk box isn't very good, and you don't have other projects, shipping for the parts will probably double or triple the cost.) Accuracy is dependent on a crystal, so if you want to get under something like 0.01% you are probably going to have to add an oven to the typical designs you will find on the web. For "a few MHZ", construction is very non-critical. Take a look at OM3CPH's designs for a starting place. .. "Kirk" wrote in message news:1151976452.561672.72470@j8g2000cwa.googlegroups.com... >I have looked at used eqpt etc and kits. Most kits are partial kits. > How I wish Heath were still in business :( > > Any recommendations for a frequency meter of good accuracy. I dont need > high frequency capability - a few MHz is good enough but I need good > accuracy. > > thanks > Kirk > KC7THL > Article: 97840 of rec.radio.amateur.homebrew From: "xpyttl" References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Subject: Re: How to calculate increase of home wireless router range? Message-ID: Date: Tue, 4 Jul 2006 08:30:46 -0400 "Highland Ham" wrote in message news:Cc2dnRvAlL-h0jfZRVnyiA@pipex.net... > Having followed today's postings on this topic , I see that there is a > wooded area between your house and shed, hence there seems to be no free > line of sight between the house and the shed. > That's why it is difficult to calculate/predict the Gain you need to > penetrate the wooded area with a 2.4 GHz signal. YES - exactly. I have been able to go laptop to laptop almost a mile with normal PCMCIA cards, using patch antennas. (Well - normal cards modified to bring out the signal to the antenna.) These antennas can be astonishingly directional. Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing amounts of gain. This translates into VERY CAREFUL aiming of the antenna. Also keep in mind that at 2.4 GHz, RG-58 ain't gonna cut it. Most of what you put in to one end of any normal coax will be sucked up by the coax and won't make it out the other end. You need to use cable appropriate to the frequency. With a wooded area, not only is it very difficult to calculate, but tiny differences in the positioning of the two ends is going to make a huge difference, as is summer to winter. Even a windy day is going to change things. Because of the small size, it can be pretty simple to build a yagi for wireless. Yagis won' t have the gain of some of the other types of antennas, but at the same time, they won't be nearly as critical. Depending on your situation, you may find a directional antenna a better choice than more power. Lots of people driving by like to "borrow" your wireless, and I personally don't like the idea of strangers roaming my LAN, even if they aren't typical crackers. (Seems to me that salesmen are the most common intruders. They have learned that they can find a wireless connection almost anywhere). I find getting coverage into the back yard, while NOT getting coverage well into the street is a bit of a challenge. Yes, I use encryption and MAC filtering, but I'd still rather not have lots of wardrivers trying to break in. .. Article: 97841 of rec.radio.amateur.homebrew From: "W3JDR" References: Subject: Re: quadrature detector & SSB Message-ID: Date: Tue, 04 Jul 2006 12:44:10 GMT It's not that easy Ben..... The I-Q demodulator in this chip doesn't include the required 90 deg audio phase shift network. That's usually one of the toughest parts of any phasing-type detector. Also, the LO phase balance is specified as 1.2 deg and the amplitude balance is specified as 0.2 dB. These imbalances would combine to give an opposite sidenabd rejection of less than 40 dB, maybe 35 dB. Not too good by modern standards. Furthermore, the detector circuits only work at IF frequencies, not RF frequencies. This implies that the internal mixer would have to be used in a downconversion mode, resulting in a requirement for an image-reject bandpass filter at the mixer input and some measure of bandpass filtering at the mixer output. On top of all this, the LO noise floor is only -100 dBc/Hz, which would probably cause pretty bad reciprocal mixing under crowded band conditions. All things considered, I think that by the time one made this chip do what it has to do for SSB/AM, one would be better off starting from scratch with more conventional components. Joe W3JDR "Ben Jackson" wrote in message news:slrneakejl.o0p.ben@saturn.home.ben.com... > On 2006-07-04, MAc wrote: >> How to use quadrature detector to demodulate cw and ssb. I want to use >> AD607 in simple project. There is Quadrature detector on "the end" with >> two outputs I&Q - and internal phase shifter. How to detest SSB simplest >> way? > > If it does all that, you just have to choose USB, LSB or AM by chosing > sum, difference or magnitude of the IQ output. > > -- > Ben Jackson > > http://www.ben.com/ Article: 97842 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Tue, 04 Jul 2006 14:57:43 +0200 Message-ID: References: W3JDR napisa³(a): > It's not that easy Ben..... > > The I-Q demodulator in this chip doesn't include the required 90 deg audio > phase shift network. That's usually one of the toughest parts of any > phasing-type detector. What will be if I treat "I" mixer as a typical product detector. Will it work? MAc Article: 97843 of rec.radio.amateur.homebrew From: "jack" References: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> Subject: Re: frequency meter Date: Tue, 4 Jul 2006 21:05:33 -0400 Message-ID: I second the HP 5328 -- you can also get very good results with the HP 3586 measurement receiverif you only need to go to some 10's of MHz. These often show up with stabilized crystal ovens. I have also used an HP5334 and much prefer the HP5328. Article: 97844 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Tue, 04 Jul 2006 15:11:22 +0200 Message-ID: References: To clarify - the idea is to build very simple receiver - Not "play with quadrature detector". AD607 look simply and small Article: 97845 of rec.radio.amateur.homebrew From: gsm@mendelson.com (Geoffrey S. Mendelson) Subject: Re: How to calculate increase of home wireless router range? Date: Tue, 4 Jul 2006 13:30:10 +0000 (UTC) Message-ID: References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> xpyttl wrote: > I have been able to go laptop to laptop almost a mile with normal PCMCIA > cards, using patch antennas. (Well - normal cards modified to bring out the > signal to the antenna.) These antennas can be astonishingly directional. > Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing amounts > of gain. There are restrictions on the RADIATED power, transmitter output power, etc of unlicensed 2.4gHz transmitters, such as WiFi. You should check them out. They vary from country to country. If you have a ham license, then you can use 2.4gHz for data transmission, but then you are restricted in transmission mode, encryption and data content. For example, the infamous Pringles can antenna was developed in the U.S. by an FBI agent in the course of an investigation. It's use as a WiFi transmission antenna is illegal in many places. The well pubicised long distance link in Egypt was illegal. Here in Israel we are limited to 100mW EIRP for civilian useage, except for ham satellite operations which are limited to 25w. BTW, there are limitations in the U.S. too, I just don't know them. 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: 97846 of rec.radio.amateur.homebrew Subject: Re: Self-heating of crystal in inverter oscillator From: Mike Monett References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 10:02:52 -0400 Ben Jackson wrote: > > Well, this might be the best advice I ever got from Usenet. I fought > every parameter in the 'HC86 inverter oscillator and lost. The fact > that it works great at 14.85MHz and the elegance of using up the extra > gates lured me in. The whole thing is very voltage sensitive (around > 1Hz/mV at the output of the gate, making it very sensitive to Rs as > well). This might be due to the propagation parameters of the gate > varying substantially with temperature and voltage. > I built a Colpitts oscillator with a plain old 2N3904 and it hasn't > moved by more than a few Hz in the hour it's been on. > Thanks! > Ben Jackson Hi Ben, I have been following this interesting thread. Thanks for posting the data. Could you do me a favor and post your 2N3904 schematic? I'd like to put it in my SPICE Crystal Analysis program and see if it can verify the performance you obtain. If you are interested, the paper is at http://tinyurl.com/qpcoz Regards, Mike Monett Article: 97847 of rec.radio.amateur.homebrew Subject: Re: Inductance Capacity meter From: Mike Monett References: <1151911418.539954.235680@v61g2000cwv.googlegroups.com> Message-ID: Date: Tue, 04 Jul 2006 10:25:28 -0400 "jack" wrote: > WB9LVI's "LMS" was described in QEX -- ultra simple -- just your sound > card and an opamp or so: > http://www.arrl.org/qex/2005/Steber.pdf there is a link to the exe > file in the PDF. > Jack Hi Jack, Thanks for posting this. It looks very interesting, but the .exe file seems to be a DLL for Visual Basic 6.0 and not the main program. I searched the article for more references to .zip and .exe, but couldn't find any. Do you have any more information on where to obtain professor Steber's program? Regards, Mike Monett Article: 97848 of rec.radio.amateur.homebrew From: "Paolo IW3ARV" Subject: Re: Inductance Capacity meter Date: 4 Jul 2006 07:34:19 -0700 Message-ID: <1152023659.154801.237240@m73g2000cwd.googlegroups.com> References: <1151911418.539954.235680@v61g2000cwv.googlegroups.com> jack ha scritto: > WB9LVI's "LMS" was described in QEX -- ultra simple -- just your sound card > and an opamp or so: > http://www.arrl.org/qex/2005/Steber.pdf there is a link to the exe file in > the PDF. I've check the QEX article but I've found that the minimum C or L range is very hight for my needs Thanks Paolo Iw3arv Article: 97849 of rec.radio.amateur.homebrew Subject: Re: Inductance Capacity meter From: Mike Monett References: <1151911418.539954.235680@v61g2000cwv.googlegroups.com> Message-ID: Date: Tue, 04 Jul 2006 10:43:33 -0400 Mike Monett wrote: > Do you > have any more information on where to obtain professor Steber's program? OK, I found it. It's http://www.arrl.org/qexfiles/LMSProg.zip (Also, more good stuff to check at http://www.arrl.org/files/) The zip is very short - 51k, but it contains the program and some auxilary files. The program ran instantly on my Win98 computer. The VB DLL was already installed in \windows\system from previous downloads. Jack, this looks very interesting and easy to do. Thanks for posting the url. Regards, Mike Monett Article: 97850 of rec.radio.amateur.homebrew From: "AndyS" Subject: Re: quadrature detector & SSB Date: 4 Jul 2006 09:18:30 -0700 Message-ID: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> References: MAc wrote: > To clarify - the idea is to build very simple receiver - Not "play with > quadrature detector". AD607 look simply and small Andy writes: While I agree with everything MAC wrote, I think a point is being missed. A Quadrature detector is normally used only for FM demodulation. It accomplishes this by limiting the signal and applying it to one port of a 90deg detector. If the limited signal is shifted 90 degrees (narrow band), the quad detector will detect FM... If the limited signal is shifted ZERO degrees, the quad detector will detect AM, and in a much more linear way than a diode type detector...... With CW, there would be no signal to zero beat with, and no audio note would be formed.... Exactly the same with SSB....all the output would be "DC"... Mac's explanation is correct for an IQ detector... In this case a local signal EQUAL to the suppressed carrier of the SSB signal has to be supplied..... I don't know how a local carrier can be synchronized to a SSB carrier that, if done really well, doesn't exist...... In Homodyne receivers, it is easy, since the transmit signal can be the LO signal..... Otherwise, it has to be "guessed" at..... With really really really stable local oscillators, the guess can be really close, and the difference will creat an error that is so small it doesn't matter... But, since you don't know the incident phase of the received signal, you have to do both I and Q and shift the IF by 90 degrees and sum (or difference, depending whether you want USB or LSB) the outputs of the two channels...... For SSB detection, the RF port is NOT shifted, the LO port is both 0 and 90 degrees, and the IF port ( I and Q) are shifted 90 and combined........ It is a hell of a lot easier to "approximate" the LO, and shift it manually until Donald Duck starts sounding human.... In older SSB rigs, this was called a "clarifier" control..... It isn't necessary in many modern systems with really really really good TCXOs and stuff.... Just my two cents worth.... If anyone disagrees, I'd be happy to learn from them where my explanation is wrong..... but I warn you, it ain't far wrong.... cause it worked for me for many many years in designing receivers for both commercial and military products ...:>))))) Andy in Eureka, W4OAH ( retired comm/radar engineer and ham for 45 years ) Article: 97851 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Tue, 04 Jul 2006 18:27:19 +0200 Message-ID: References: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> AndyS wrote: > A Quadrature detector is normally used only for FM demodulation. Yes. but (from Analog Devices): "...Applications of the AD607 include narrowband systems with a high first IF (21.4 MHz to 300 MHz) and a second IF at 10.7 MHz, 455 kHz, or 450 kHz. These include Dual Conversion IS136, GSM, TETRA, and MSAT Receivers; and Single or Dual Conversion VHF and HF AM, SSB, CW, or QPSK Receivers... " But :-) I did not find any SSB application :-( So I need an example. Just my two cents worth.... If anyone disagrees, I'd be happy to > learn from them where my explanation is wrong..... but I warn you, > it ain't far wrong.... cause it worked for me for many many years > in designing receivers for both commercial and military products > ...:>))))) Andy Thanks for your cents, rather dollars. PS there is internal quadrature pll in ad607. MAc Article: 97852 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1aea0pztwz017$.67s063ytjufg.dlg@40tude.net> <4gveasF1oim3nU1@individual.net> Message-ID: Date: Tue, 04 Jul 2006 16:58:50 GMT On Tue, 4 Jul 2006 11:03:49 -0400, Peter Pan wrote: >> Can you help me roughly CALCULATE how to increase the range of my >> home Internet wireless WiFi setup to a shed 300 feet away ... > I Had a linksys WRT54G in the house attached to my sat, > and used one of the 4 router outputs to daisy chain one to the wan input of > another WRT54G (same ssid) and a semi-directional antenna pointed towards > the garage about 500ft away, Hi Peter Pan, Oh my! Is "wireless" daisy chaining workable? Is it that easy? I did not think I could just daisy chain multiple routers! Are you sure? (My shed has no power but I think I could run an extension cord into it if that would make things workable.) Would I just set the second Linksys router (which, amazingly, has it's own wikipedia entry at http://en.wikipedia.org/wiki/WRT54G) in the shed on the same channel (SSID=12, name = default) as the first router in the house? That is, could I put one linksys WRT54G in the house (perhaps with one antenna replaced with a 7 dBd higher-gain directional antenna); and then put the other Linksys WRT54G in the shed 300 feet away (perhaps with one of it's antennas replaced with a similar 7 dBd directional antenna)? Or, is it best to hardwire with cat5 the first router downstairs in the house to the second router, say upstairs in the attic window pointing the antenna toward the shed? I didn't even know that two routers could be daisy chained. That might solve my dilemma. Can someone confirm that two routers could be daisy chained either by wire cat5 cable or by wireless signals as long as they use the same SSID channel and network name? That solution seems to easy to be true ... Beverly Article: 97853 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> Message-ID: <8yqb919lnyrr.1f50bcplmn26a.dlg@40tude.net> Date: Tue, 04 Jul 2006 17:15:39 GMT On Tue, 04 Jul 2006 09:07:39 -0500, bearclaw@cruller.invalid wrote: > Here is an easy way to hack your $60 wireless router into a $600 > router (they use Linksys as the example): Wow. I've never "modified" a router before but that is interesting that one can increase the $75 Linksys WRT54G router (http://en.wikipedia.org/wiki/WRT54G) RF output from 28 millwatts up to 251 milliwatts (http://tinyurl.com/lpk7w). Being true to the original intent of this thread, how do I CALCULATE what that does to my range? Is this 9 dBd calculation of the modification roughly correct? a) Power gain = Power2/Power1 = 251/28 milliwatts = 9x power gain b) Range gain = sqrt(Power gain) = sqrt(9) = 3X range gain c) Range = original range * range gain = 100 feet * 3 = 300 feet Beverly Article: 97854 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Message-ID: <410kzzswtlgd$.1jcc2o88kv83h$.dlg@40tude.net> Date: Tue, 04 Jul 2006 17:18:49 GMT On Tue, 04 Jul 2006 11:48:12 +0100, Highland Ham wrote: > Beverly Erlebacher wrote: >> Can you help me roughly CALCULATE how to increase the range of my home >> Internet wireless WiFi setup to a shed 300 feet away from my house? >> >> Presently, I can walk about half the way through the wooded area to the >> shed with my laptop in hand before I lose the connection to the PCMCIA >> 802.11b,g Linksys card. Basically I need to gain 150 feet in "range". >> >> But how? > ==================================================== > Having followed today's postings on this topic , I see that there is a > wooded area between your house and shed, hence there seems to be no free > line of sight between the house and the shed. > That's why it is difficult to calculate/predict the Gain you need to > penetrate the wooded area with a 2.4 GHz signal. > > If you wish to use the laptop inside the shed at a fixed location it > MIGHT be good enough if you install a corner reflector yagi (High > Gain)antenna at both the house AND the shed. However then your laptop > needs a plug-in PCMCIA WiFi tansceiver with a connection for an external > antenna. > One of such units is the Make: Buffalo - Air Station Turbo G ,High Power > -unit which also has a built-in antenna. > Note : The coaxial cable between the 2 devices and their associated > antenna should be limited to only a few metres because of the high > frequency being 2.4GHz > > Communication here is 2 way . Your laptop might receive the ( antenna > amplified) signal from your router located in the house ,but that does > not mean the router will receive the signal from the laptop without > additional facilities at the laptop. > > Again , because of the probably partly obstructed path (wooded area) it > is difficult making any sensible calculations. > > Frank GM0CSZ / KN6WH Hi Highland Ham, I see there are multiple solutions. Probably on the end of my list is adding a wire to the laptop because then it wouldn't be wireless. Still, it's an intriguing idea (I never knew laptops could have fixed antenna's connected to them by wire). If I do use two antennas, does that "add" the gain? a) Antenna 1 transmits with a directional gain of, say 7 dBd b) Antenna 2 receives with a directional gain of, say 7 dBd c) Does that get me a 14 dBd overall gain? Beverly Article: 97855 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <4mpka2djd7m3mf92pckoapdker2ek9hjb7@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 17:40:18 GMT On Tue, 04 Jul 2006 06:11:27 -0700, Dan Richardsonk6mhe wrote: > If your goal is to increase your range then add an extender > (hams would prefer to call them repeaters). Oh my. The seemingly perfect option. I had come across the concept of wireless "repeaters" in my initial googling before I went to the store, e.g., in this Microsoft "how to increase range" article http://www.microsoft.com/athome/moredone/wirelesstips.mspx and in this "Extending WLAN Range" article http://www.wi-fiplanet.com/tutorials/article.php/1571601 The repeater most often recommended was the "Linksys Wireless-G Range Expander WRE54G". However, I can't find that 802.11b,g WiFi repeater (aka range expander or extender) anywhere in the local stores. The salesperson who sold me the $300 USD 802.11n router and PCMCIA card combination said they didn't work so they dropped it. This solution seems to be the most elegant of all (but someone else suggested just using a second router). Can someone unconfusify the situation? Is placing a repeater (on the same SSID) in the shed really the same as adding a second router instead? Beverly Article: 97856 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <4mpka2djd7m3mf92pckoapdker2ek9hjb7@4ax.com> Message-ID: <150qlbhdez36g$.1ougzyb53jjsu.dlg@40tude.net> Date: Tue, 04 Jul 2006 17:47:27 GMT On Tue, 04 Jul 2006 08:17:19 -0700, David wrote: > A "range extender" or "repeater" will cut the speed in half. Hi David, Interesting this speed difference. I'm worried about RANGE and all of a sudden other factors come into play! Thank you for enlightening me. I know more now than I ever did from you wonderful guys! As I noted to someone else just now, I DID try to find the "Linksys Wireless-G Range Expander WRE54G" WiFi repeater in the local stores but they did not exist in any of the three stores I checked. Also, some of the articles talk about an "access point" (http://www.wi-fiplanet.com/tutorials/article.php/1571601). Can someone tell me what part of my setup I would call the "access point"? Beverly Article: 97857 of rec.radio.amateur.homebrew From: Beverly Erlebacher Subject: Re: How to calculate increase of home wireless router range? References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <6_xqg.86010$uP.64508@newsfe2-gui.ntli.net> Message-ID: <11of8oney2ztt.1rzsok8gvo9mf.dlg@40tude.net> Date: Tue, 04 Jul 2006 18:06:56 GMT On Tue, 04 Jul 2006 17:57:22 GMT, stephen wrote: > but - you mentioned you could run power out to your shed. Why not plumb it > in for power and networking? > then you can add a separate access point there and avoid antennae, gain, > loss through leaves and the rest. Hi Stephen, I'm confused about this "access point" thing. Is that the same as a "router"? Is it as simple as buying a second router (routers are familiar to me) and just hooking that second router to the first router by cable and that would extend my range by the distance of the cable connecting the two routers? This is a key confusion point for me! Beverly Article: 97858 of rec.radio.amateur.homebrew From: "Rod Speed" Subject: Re: How to calculate increase of home wireless router range? Date: Wed, 5 Jul 2006 04:11:35 +1000 Message-ID: <4gvpaqF1ojse0U1@individual.net> References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <4mpka2djd7m3mf92pckoapdker2ek9hjb7@4ax.com> <150qlbhdez36g$.1ougzyb53jjsu.dlg@40tude.net> Beverly Erlebacher wrote: > On Tue, 04 Jul 2006 08:17:19 -0700, David wrote: >> A "range extender" or "repeater" will cut the speed in half. > > Hi David, > > Interesting this speed difference. I'm worried about RANGE and all of > a sudden other factors come into play! Thank you for enlightening me. > I know more now than I ever did from you wonderful guys! > > As I noted to someone else just now, I DID try to find the "Linksys > Wireless-G Range Expander WRE54G" WiFi repeater in the local stores > but they did not exist in any of the three stores I checked. > > Also, some of the articles talk about an "access point" > (http://www.wi-fiplanet.com/tutorials/article.php/1571601). > Can someone tell me what part of my setup I would call the "access point"? The wireless part. Article: 97859 of rec.radio.amateur.homebrew From: "Rod Speed" Subject: Re: How to calculate increase of home wireless router range? Date: Wed, 5 Jul 2006 04:11:43 +1000 Message-ID: <4gvpb5F1oatv7U1@individual.net> References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> <1i8d1tcl66zdn$.7knr5ebizk69.dlg@40tude.net> Beverly Erlebacher wrote: > On Tue, 04 Jul 2006 05:50:02 -0400, Rôgêr wrote: >>> Do folks here recommend the pringles cantenna or the pie tin >>> antenna for my 2-antenna router 802.11b,g directional application >>> where I need to also feed the computers within the house in >>> addition to the shed 300 feet away? >> >> I use panel antennas almost exclusively, exceptions being some 24dbi >> mesh antennas for backhaul. > > Hi Rôgêr, > > After reading all the articles posted, I now understand that: > > a) The pringles can is hip; but it's the worst performer > http://www.oreillynet.com/cs/weblog/view/wlg/448 > (it's not even metal foil lined and it's too small in diameter) > > b) The coffee cantenna is more effective than the pringles cantenna > http://www.oreillynet.com/cs/user/view/wlg/1124 > > c) The dish antenna is the simplest of all and almost as good > http://www.freeantennas.com/projects/template > http://www.freeantennas.com/projects/template2/index.html > > I also see, as Rod Speed so kindly noted, that the give and take is > that we lose range in some directions in favor of range in the > desired direction. Fair enough. > > My one question is a practical one. > > Why are there two antennas on my router anyway? That gives a more reliable coverage than with one. > Is one transmit and the other receive? > Or are they both transmit and receive? They're normally both transmit and receive. > Given I have TWO omnidirectional antennas on my wireless router, > if I put the parabolic dish antenna on one to direct it to my shed, > does that allow the OTHER antenna to radiate around the house > to handle the other computers roving around the house? Yes. Article: 97860 of rec.radio.amateur.homebrew From: "xpyttl" References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Subject: Re: How to calculate increase of home wireless router range? Message-ID: Date: Tue, 4 Jul 2006 14:38:24 -0400 "Geoffrey S. Mendelson" wrote in message news:slrneakr45.39f.gsm@cable.mendelson.com... > If you have a ham license, then you can use 2.4gHz for data transmission, > but then you are restricted in transmission mode, encryption and data > content. And wireless channels, as well. Some of the channels are outside the U.S. ham bands. Since this is an amateur radio newsgroup, I made the (possibly rash) assumption that OP was aware of these limitations. For amateurs in the U.S., the main issue is encryption. Few of us can afford to get anywhere near the power limits at these frequencies! .. Article: 97861 of rec.radio.amateur.homebrew From: Allodoxaphobia Subject: Re: How to calculate increase of home wireless router range? Date: 4 Jul 2006 19:31:00 GMT Message-ID: References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> On Tue, 4 Jul 2006 08:30:46 -0400, xpyttl wrote: ... > Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing amounts > of gain. ...... Sigh... If only that were true! HI!HI! Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 *** Killfiling google posts: Article: 97862 of rec.radio.amateur.homebrew From: Bob Subject: FS: Meters Message-ID: Date: Tue, 04 Jul 2006 21:06:40 GMT The following panel meters are all dc moving coil (D'Arsonval) types except as noted. MFR SCALE TYPE PRICE REMARKS Ammon 0-50-100 1.75" square $10 (2-0-2 mA FS, zero center) BA 0-1500 V 3" square 10 (200 uA FS) Beede 0-1 mA 4"x5" rect 10 Bird 0-15-60 W 3.5" round Free (bad movement) G.E. 0-10 Vac 3.5" square 5 (scratch on face) G.E. 0-500 mA 3.5" round 10 G.E. 0-500 mA ac 3.5" square 10 HP 0-10 V, -10-+3 dBm 2.25" half round 7 (1 mA FS) HP 0-100% Modulation 4.25" square 25 (50 uA FS) Knight 0-50 uA 3"x4.5" rect 10 Modutec -10-+2 dBm 3"x3.5" rect 10 (1 mA FS) Shurite -20-+3 VU 1.5x0.5 edge 10 (NIB) Sierra 0-10-50 W 3.5" square 5 (may have cracked jewel) Simpson 0-1 mA 1.75" square 7 Simpson 0-1.0 3.5" round 5 (0.5 mA FS) Simpson 0-25 uA 2.5" square 5 (broken housing) Simpson 0-250 Vac 3.5" square 20 (NOS) Sun 0-1 mA 2.5" round 7 Triplett 0-250 Vac 4" square 25 (NOS) Triplett 0-500 A 2.5" square 5 (7.5 mA FS, broken mounting screws) Weston 0-50 mA 3.5" round 10 Weston 1-10-Inf VSWR 3.5" round 10 (30 uA FS) Weston 50-0-50 mA 3.5" round 20 (zero center) Above prices do not include shipping from 94024. Will entertain offers on any or all. Bob, W6NBI Article: 97863 of rec.radio.amateur.homebrew From: "AndyS" Subject: Re: quadrature detector & SSB Date: 4 Jul 2006 14:09:09 -0700 Message-ID: <1152047349.512115.325270@a14g2000cwb.googlegroups.com> References: > > Andy Thanks for your cents, rather dollars. > > PS there is internal quadrature pll in ad607. > > MAc Andy responds; Ok.. I admit that I didn't go find the AD607 and study it before replying to Mac... However,,, I'll bet you a dollar that the fellow who wrote the app note that Mac refers to has a hell of a lot less experience than either Mac or myself..... not that I would expect a young app note writer to overstate the applications of his product ( big damn grin )... The AD606 really makes a great tie-tac if you glue an alligator clip to it, tho I've never actually seen one for sale... :>))))))) if the gilbert cell, or single ended long tailed pair multiplier used as a quad detector allows external coupling to the ports, it can be used as a BFO for CW or SSB,..., HOWEVER, having a limiting stage in the linear path of such a device is NOT a great idea.... Sure, it can be made to work, but..... well, heck... I've built a LOT of things that were really bad ideas, and I try not to duplicate them again, or tell others about them.... especially in app notes that I've made input to...... I've seen the MC3372 used as an SSB receiver in either Ham Radio or some such.... and I never seriously considered doing it myself since the limitations were so obvious.... An 811A can be used a a product detector also, but the manufacturers don't advertise it as such,...... because it is a REALLY BAD idea.... If a fellow wants a simple CW/SSB receiver, a much better idea is to use something like an NE602..... I've done that, for a home project , and it works OK,..... but certainly not something I'd try to produce as a receiver for Bendix, Texas Instruments, or Raytheon...... There's a limit to how far one should stretch an application..... Thanks Mac, for your input. I bet we agree on almost everything..... Andy W4OAH Article: 97864 of rec.radio.amateur.homebrew From: "W3JDR" References: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> <1152047349.512115.325270@a14g2000cwb.googlegroups.com> Subject: Re: quadrature detector & SSB Message-ID: Date: Tue, 04 Jul 2006 21:19:29 GMT > Ok.. I admit that I didn't go find the AD607 and study it before > replying..... >.....HOWEVER, having a limiting stage in the > linear path of such a device is NOT a great idea --------------------- Andy, You really should go and read the data sheet on the AD607. 1) It's a linear component with no limiter stages 2) It has an "I-Q" detector, not a "quadrature detector". Comparing it to the MC3372, or any other FM detector chip, is as far off base as comparing it to an 811. However, having said all that, I think we would agree that there are better and simpler solutions for amateur SSB and AM applications. Joe W3JDR "AndyS" wrote in message news:1152047349.512115.325270@a14g2000cwb.googlegroups.com... > > >> Andy Thanks for your cents, rather dollars. >> >> PS there is internal quadrature pll in ad607. >> >> MAc > > > Andy responds; > > Ok.. I admit that I didn't go find the AD607 and study it before > replying > to Mac... However,,, I'll bet you a dollar that the fellow who wrote > the > app note that Mac refers to has a hell of a lot less experience than > either Mac or myself..... not that I would expect a young app note > writer to overstate the applications of his product ( big damn grin > )... > The AD606 really makes a great tie-tac if you glue an alligator clip > to it, tho I've never actually seen one for sale... :>))))))) > > if the gilbert cell, or single ended long tailed pair multiplier > used as a > quad detector allows external coupling to the ports, it can be used as > a BFO for CW or SSB,..., HOWEVER, having a limiting stage in the > linear path of such a device is NOT a great idea.... Sure, it can be > made > to work, but..... well, heck... I've built a LOT of things that were > really > bad ideas, and I try not to duplicate them again, or tell others about > > them.... especially in app notes that I've made input to...... > I've seen the MC3372 used as an SSB receiver in either Ham Radio > or some such.... and I never seriously considered doing it myself since > the limitations were so obvious.... > > An 811A can be used a a product detector also, but the > manufacturers > don't advertise it as such,...... because it is a REALLY BAD idea.... > If a fellow wants a simple CW/SSB receiver, a much better idea is to > use something like an NE602..... I've done that, for a home project , > and > it works OK,..... but certainly not something I'd try to produce as a > receiver for Bendix, Texas Instruments, or Raytheon...... There's a > limit > to how far one should stretch an application..... > > Thanks Mac, for your input. I bet we agree on almost > everything..... > > Andy W4OAH > Article: 97865 of rec.radio.amateur.homebrew From: gsm@mendelson.com (Geoffrey S. Mendelson) Subject: Re: How to calculate increase of home wireless router range? Date: Tue, 4 Jul 2006 21:31:06 +0000 (UTC) Message-ID: References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <6_xqg.86010$uP.64508@newsfe2-gui.ntli.net> <11of8oney2ztt.1rzsok8gvo9mf.dlg@40tude.net> Beverly Erlebacher wrote: > I'm confused about this "access point" thing. An access point is a device with an ethernet port on one side and a wifi port on the other. In technical terms it would be called a "bridge". It "bridges" two seperate network segments, although in this case they use different topologies (100Base-T and WiFi). > Is that the same as a "router"? The usual WiFi router consists of a four port ethernet hub (LAN ports), a seperate single ethernet port (WAN port) and a WiFi access point. It is set up to "route" between the single (aka WAN) port and the other two ports, the LAN and WiFi. Most of what it does for routing is NAT (network address translation) and some sort of IP tunneling. If you ignore the WAN port and just use the LAN ports, you have a four port hub and an access point. > Is it as simple as buying a second router (routers are familiar to me) and > just hooking that second router to the first router by cable and that would > extend my range by the distance of the cable connecting the two routers? Yes. Just make sure to use the LAN ports. It would be best to use different channels. Most WiFi clients are smart enough to use the channel that is the strongest if they have access points on more than one with the same SSID. Make sure to use encryption. Encryption is NOT to keep your data safe, nothing can do that. If someone is intent on accessing your network, WEP encryption will not keep them out. What it is for is to convince the guy driving down the street looking for an open network to send out SPAM, or "share" kiddie porn, to drive on. Unfortunately, most users don't even change the SSID of their network, let alone set an encryption key. Having tuned in late, if you want to have an open network, look up PublicIP. It's a "live cd" that runs on a PII or better (x86) computer and provides all the functions you need to offer a secure and safe open network. 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: 97866 of rec.radio.amateur.homebrew From: gsm@mendelson.com (Geoffrey S. Mendelson) Subject: Re: How to calculate increase of home wireless router range? Date: Tue, 4 Jul 2006 21:31:07 +0000 (UTC) Message-ID: References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> <1i8d1tcl66zdn$.7knr5ebizk69.dlg@40tude.net> <4gvpb5F1oatv7U1@individual.net> Rod Speed wrote: >> Is one transmit and the other receive? >> Or are they both transmit and receive? > > They're normally both transmit and receive. That's a shame. Here in Israel we are limited to 100mw EIRP, which severly limits the transmit antenna. There is NO limitation on the receive antenna. 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: 97867 of rec.radio.amateur.homebrew From: Ben Jackson Subject: Re: Self-heating of crystal in inverter oscillator References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 17:17:41 -0500 On 2006-07-04, Mike Monett wrote: > Ben Jackson wrote: > >> I built a Colpitts oscillator with a plain old 2N3904 and it hasn't >> moved by more than a few Hz in the hour it's been on. > > Could you do me a favor and post your 2N3904 schematic? ___ +5V .--|33k|---+ | | | |/ .-o---o----| 2N3904 | | |> | --- | | --- .--o----> _-_100p| | | |___| o---' .-. - | | | 150 25Mhz | --- | | | --- '-' | 100p| | o-----o------' | === GND The 33k/150 were chosen to get CMOS compatible output. The circuit will oscillate with much higher values for each. The two 100p might be slightly too high for the 18p crystal I'm using, but I didn't tune those carefully because I want to pull the crystal slightly, and in my actual circuit the grounded leg of the crystal is actually in series with a variable capacitance to tune the VCXO. (created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de) -- Ben Jackson http://www.ben.com/ Article: 97868 of rec.radio.amateur.homebrew From: "Rod Speed" Subject: Re: How to calculate increase of home wireless router range? Date: Wed, 5 Jul 2006 08:27:05 +1000 Message-ID: <4h089vF1pk0rnU1@individual.net> References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> <12ak2k0hqa77dae@corp.supernews.com> <1sr34qtndtz8m.8y1znh8b5w9o$.dlg@40tude.net> <1i8d1tcl66zdn$.7knr5ebizk69.dlg@40tude.net> <4gvpb5F1oatv7U1@individual.net> Geoffrey S. Mendelson wrote > Rod Speed wrote >>> Is one transmit and the other receive? >>> Or are they both transmit and receive? >> They're normally both transmit and receive. > That's a shame. Here in Israel we are limited to 100mw EIRP, which severly > limits the transmit antenna. There is NO limitation on the receive antenna. A receive antenna has no EIRP, it doesnt radiate any real power. Article: 97869 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Wed, 05 Jul 2006 00:32:57 +0200 Message-ID: References: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> <1152047349.512115.325270@a14g2000cwb.googlegroups.com> AndyS napisa?(a): I bet we agree on almost > everything..... Generally Yesss But (always but) :-)))) I never used mc3372 as ssb rx, but permanently used mc3362. But... - mc3362 id dual conversion RX and i used second mixer as a product detector leaving original fm detector "out of business". I am not good in quadrature detectors, and i don't know what (technically) is mixer (rather mixers) in ad607. I have only 1 piece of IC, it's surface mount, and I'm afraid, that if I use it in my test board I will have nothing to use in my receiver. Of course I used ne602/612 in many constructions, (genetally trx with switched BFO/VFO - Atlas idea), but this time the idea is to use as low elements as possible to build a rx with "quite good" performance. Serious (other or better ;-) ) idea in my wokshop is TGX with1st mixer on fst3125 with companion of ad600 IF ampli (only one) in typical application (application note with simple ad590 and one transistor AGC) - not this "high performance agc system from Exp. Methods... On the other hand - it is the best way in our HAM life - to use parts in the way, which was not inntended by "creators". It's a part of our love to ham radio :-) Nice and inspirating talk Andy. Greetings from Poland MAc sp9mrn Article: 97870 of rec.radio.amateur.homebrew Subject: Re: Self-heating of crystal in inverter oscillator From: Mike Monett References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 18:34:03 -0400 Ben Jackson wrote: > The 33k/150 were chosen to get CMOS compatible output. The circuit will > oscillate with much higher values for each. > The two 100p might be slightly too high for the 18p crystal I'm using, > but I didn't tune those carefully because I want to pull the crystal > slightly, and in my actual circuit the grounded leg of the crystal is > actually in series with a variable capacitance to tune the VCXO. > (created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de) > Ben Jackson Hi Ben, Thanks. What is the nominal setting of the cap in series with the crystal? 18pf or so? Do you have any info on the crystal, such as make and model? Or any idea what the series resistance might be? Would you like me to post the results to my web site? Regards, Mike Monett Article: 97871 of rec.radio.amateur.homebrew Subject: Re: Self-heating of crystal in inverter oscillator From: Mike Monett References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 18:36:08 -0400 Mike Monett wrote: > Would you like me to post the results to my web site? To clarify - so you can see the waveforms? Regards, Mike Monett Article: 97872 of rec.radio.amateur.homebrew From: Ted Subject: Re: Inductance Capacity meter Message-ID: <3fsla2lsmg5vp3i84udf3t5ev9pr0cmfo9@4ax.com> References: <1151911418.539954.235680@v61g2000cwv.googlegroups.com> Date: Tue, 04 Jul 2006 19:00:42 -0400 The Columbus, Ohio QRP Club did a group build of an LC meter based on the project in "Everyday Practical Electronics" magazine, February 2004 issue. The URL is http://www.qsl.net/cqrp/projects.html. For some reason, the link to the members' meters is no longer working. This meter has slightly better capacitance range specs than the AADE meter, as reported by ARRL on the website awhile ago. If you are interested, I am building this meter, and I can give you some additional information about it. Please email me directly, removing the ** from my email address. Regards, Ted KX4OM Article: 97873 of rec.radio.amateur.homebrew From: Ben Jackson Subject: Re: Self-heating of crystal in inverter oscillator References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 18:28:20 -0500 On 2006-07-04, Mike Monett wrote: > Ben Jackson wrote: > >> The two 100p might be slightly too high for the 18p crystal I'm using, > > Hi Ben, Thanks. What is the nominal setting of the cap in series with the > crystal? 18pf or so? The "varicap" is actually a red LED, which G0UPL characterized as about 30p down to about 20p over 0..5V: http://www.hanssummers.com/radio/varicap/index.htm > Do you have any info on the crystal, such as make and model? It's a Digi-Key X231-ND, mfg p/n ECS-250-18-4-F. Digikey has the datasheet. I think the ESR was 40 ohms. > Would you like me to post the results to my web site? Sure. -- Ben Jackson http://www.ben.com/ Article: 97874 of rec.radio.amateur.homebrew From: "AndyS" Subject: Re: quadrature detector & SSB Date: 4 Jul 2006 16:47:48 -0700 Message-ID: <1152056868.087427.226000@m73g2000cwd.googlegroups.com> References: W3JDR wrote: > Andy, > > You really should go and read the data sheet on the AD607. Andy replies, You're right. I should have dug a little further before I started rattling off "the world according to Andy".... When the OP started with the "quadrature det" question and the reply was concerning I/Q , I just jumped right in... Sorry I wasted your time...... Andy W4OAH Article: 97875 of rec.radio.amateur.homebrew From: "AndyS" Subject: Re: quadrature detector & SSB Date: 4 Jul 2006 17:18:30 -0700 Message-ID: <1152058710.356360.61600@m73g2000cwd.googlegroups.com> References: MAc wrote:. I have only 1 piece of > IC, it's surface mount, and I'm afraid, that if I use it in my test > board I will have nothing to use in my receiver. > Andy writes: God how I hate surface mount.... It used to be that I could send away for a freebee, or buy a chip from Digikey, and get normal, civilized, 1/10 lead spacing pins that I could use in a socket, or use the pins as tie point for "dead bug"..... I could build a circuit up as fast as I could go and the connecting of the parts together was an insignificant part of the process... NOW, for the last several years, all freebees I have received have been surface mount. I have to work under a magnifying glass, with a special thingy for my soldering iron, and use small pieces of copper wire strand that I get out of lamp cord to expand the chip to the point where I can actually attach resistors and capacitors.... it takes more time to expand the surface mount than to build the rest of the circuit... As a result, I lose enthusiasm a lot...... I have a few things that I have done with surface mount, but I long for the good old days...... Fortunately, I have about 30 years of accumulated freebees that I haven't gotten around to using, and can usually come up with a way to build something.... However, the miracle chips (as I call them) that Analog Dev, and others, are coming out with are just too damn much trouble for me....... If anyone here has some SIMPLE solutions for the surface mount thing, that does NOT include making a custom PC board, I'd like to learn about them..... Andy in Eureka, Texas Article: 97876 of rec.radio.amateur.homebrew Subject: Re: Self-heating of crystal in inverter oscillator From: Mike Monett References: <8vvca294jm11qma8glha502eu4rrmgqgkv@4ax.com> Message-ID: Date: Tue, 04 Jul 2006 21:28:23 -0400 Ben Jackson wrote: > It's a Digi-Key X231-ND, mfg p/n ECS-250-18-4-F. Digikey has the > datasheet. I think the ESR was 40 ohms. >> Would you like me to post the results to my web site? > Sure. Hi Ben, I found the ECS spec at http://www.ecsxtal.com/search.html The numbers are: Shunt capacitance C0 7pf drive level 0.5mW maximum max esr 30 ohms Using these values plus the standard beta value supplied with the SPICE model for the 2N3904, the oscillator runs pretty good. It doesn't clip, and puts out a good signal to drive CMOS. But the crystal dissipation is about 5.88 milliwatts, or about 11.7 times the max spec value. Since this is so far above spec, there's not much reason to go further and spend the time to post the waveforms. Regards, Mike Monett Article: 97877 of rec.radio.amateur.homebrew Date: Tue, 04 Jul 2006 20:22:58 -0700 From: "Dana H. Myers" Subject: Re: quadrature detector & SSB References: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> <1152047349.512115.325270@a14g2000cwb.googlegroups.com> <1152058710.356360.61600@m73g2000cwd.googlegroups.com> Message-ID: <4qudnSy48p4XrTbZnZ2dnUVZ_oOdnZ2d@comcast.com> AndyS wrote: > If anyone here has some SIMPLE solutions for the surface mount thing, > that does NOT include making a custom PC board, I'd like to learn > about them..... Take a look at Surfboards, stocked by Digi-Key: http://dkc3.digikey.com/PDF/T062/1634.pdf Dana K6JQ Article: 97878 of rec.radio.amateur.homebrew From: Straydog Subject: Garage hamshacks? Here is my garage "secret lab"... Date: Wed, 5 Jul 2006 02:03:43 -0400 Message-ID: (FYI/FWIW) Recently there were a lot of comments on using a garage as a hamshack. My problem was not the hamshack, but where to build my "retro" tube-based ham gear (HF) and my garage gets cold in the winter (30s F and below at worst) and too hot (90 F) and humid in the summer. So I decided to build a "cubicle" out of plywood (5/8" for me, leftover from a hurricane passby that I used to cover our most expensive windows). So I had these pieces of 4' x 6' that I put together to make a cubicle 6' high, 4' wide, and 8' deep, and put in a 18" wide "bench" (made out of a piece of lam pine about 6-7' long. This gets the drill noises, the soldering smoke, and all the little metal shavings, drillings, file dust, etc., out of the house and away from our rugs and somewhere where I don't have to be constantly cleaning it up. For the winter, a standard electric space heater easily warms up the inside in less than 1/2 hour, and in the summer, a small A/C cools it off in minutes. The A/C vents the hot air into the garage but it does not seem to warm up the garage much beyond what it warms up in normal hot weather (I mention this because the warranty says it will be voided if you do this, but I'm only doing this once a week all, or as much of the day, as possible). On the A/C, many will collect significant amounts of condensed water and then excess will drip out on the "outside" but I've found in such a small cubicle that running the A/C for many hours does not cause significant amounts of water to accumulate and perhaps this is due to the small volume of the cubicle and once it is dehumidified, not much new water vapor enters over a whole afternoon or more. I mention this because I was concerned about having a constant drip of water onto the garage floor. This has not happened yet (not a drop has come out). For anyone who wants to see images of this cubicle (for building stuff), they along with images of some of my homebrew gear, kludge-ugly-all-from- the-junkbox, can be found at: http://www.panix.com/~asd Just look for the links to the "secret lab" and click on them. FYI/FWIW: The rest of that index page lists the done projects and the in progress projects (as well as pics of prior rigs of mostly commercial gear I've had during most of my ham career). 73 Art, W4PON Article: 97879 of rec.radio.amateur.homebrew From: "xpyttl" References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> Subject: Re: How to calculate increase of home wireless router range? Message-ID: Date: Wed, 5 Jul 2006 08:18:49 -0400 hehe -- getting gain at the antenna isn't such a big deal ... getting the goo TO the antenna is a whole 'nuther can of worms. It's pretty easy to come up with 10 dB of gain and 20 dB of feedline loss! Of course, for WiFi, we're often interested in gain AND omnidirectional -- that is something of a challenge. .. "Allodoxaphobia" wrote in message news:slrnealgn5.2ffv.bit-bucket@shell.config.com... > On Tue, 4 Jul 2006 08:30:46 -0400, xpyttl wrote: > > ... >> Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing >> amounts >> of gain. ...... > > Sigh... If only that were true! HI!HI! > > Jonesy > -- > Marvin L Jones | jonz | W3DHJ | linux > 38.24N 104.55W | @ config.com | Jonesy | OS/2 > *** Killfiling google posts: Article: 97880 of rec.radio.amateur.homebrew From: "Robert Lacoste" Subject: EN300220 and phase noise Date: Wed, 5 Jul 2006 14:25:04 +0200 Message-ID: <44abafa2$0$850$ba4acef3@news.orange.fr> Hi all, Any EN 300-220 European standard guru out there ? I have some difficulties to deduce the maximum phase noise profile of a transmitter from this standard in the case of a very narrow bandwidth transmitter (say 10KHz bandwidth, operating in a non-standard VHF frequency band) : - Standard gives a limitation of the transmitted power in the adjacent channels (10µW integrated over each adjacent channel). Fine - Standard gives a limitation for the spurious emissions (-36/-54dBm under 1GHz with 100KHz spectrum analyzer bandwidth depending on the frequency). Fine. But what is the maximum noise or side modulation levels say 2, 3 or 10 channels away from the carrier ? My first assumption was that the "spurious" specification was applicable, but with a 100KHz resolution bandwidth I would be measuring the carrier power if I do the measurement even 5 channels away >from the carrier... Any help welcome... Friendly yours, Robert Article: 97881 of rec.radio.amateur.homebrew From: steve.balstone@hotmail.co.uk Subject: Re: Questions about I.F. Transformers Date: 5 Jul 2006 06:01:14 -0700 Message-ID: <1152104474.401430.37870@m79g2000cwm.googlegroups.com> References: <1151624454.814545.127930@p79g2000cwp.googlegroups.com> Jody wrote: > I can't seem to find any I.F. transformers for 465 KHZ. I was wondering > if you can use the 455 khz ones instead without changing any other > components. I'm building a reciever that calls for 465. Can a 455 be > tuned this high using the slug? or does anyone know of a source for > these parts. Any advice would be greatly appreciated. It'll tune to 465Khz no problem. But if not, use an aluminium slug instead of the ferrite one. This will have the opposite effect to the original one. ie - more aluminium inside the transformer = Higher operating frequency Stephen Balstone steve balstone Article: 97882 of rec.radio.amateur.homebrew From: gsm@mendelson.com (Geoffrey S. Mendelson) Subject: Re: How to calculate increase of home wireless router range? Date: Wed, 5 Jul 2006 13:30:03 +0000 (UTC) Message-ID: References: <2hqacpnj1nwj$.1683sqqzgbbo2$.dlg@40tude.net> xpyttl wrote: > hehe -- getting gain at the antenna isn't such a big deal ... getting the > goo TO the antenna is a whole 'nuther can of worms. It's pretty easy to > come up with 10 dB of gain and 20 dB of feedline loss! Of course, for WiFi, > we're often interested in gain AND omnidirectional -- that is something of a > challenge. POE! POE! POE! (Power over ethernet). Put the access point at the antenna, run a cat-5 cable (4 twisted pairs) to it. Four get used for the network connection, 4 get used for DC. Not only does it work well, but CAT-5 wire is cheap, 2.4gHz low loss coax is not. 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: 97883 of rec.radio.amateur.homebrew From: Christopher Cole Subject: Re: IEEE Standard for RF Safety Levels Message-ID: Date: Wed, 05 Jul 2006 13:41:38 GMT On page 26 (PDF page 30) the FCC's Human Exposure to RF Guidelines document, http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65c.pdf There is a nice chart for MPE limits. However, there is no information given for frequencies below 300kHz. Does anyone know what the MPE limits would be for both electric and magnetic field strength at 80kHz? Thanks, -Chris -- /> Christopher Cole <\ <\ << Cole Design and Development \\ email: cole@coledd.com \\ \\ Computer Networking & Embedded Electronics \\ web: http://coledd.com >> \> \> Subject: Re: IEEE Standard for RF Safety Levels Date: Wed, 5 Jul 2006 11:56:05 -0400 Message-ID: References: On Wed, 5 Jul 2006, Christopher Cole wrote: > On page 26 (PDF page 30) the FCC's Human Exposure to RF Guidelines document, > > http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65c.pdf > > There is a nice chart for MPE limits. However, there is no information given > for frequencies below 300kHz. Does anyone know what the MPE limits would > be for both electric and magnetic field strength at 80kHz? I'm going to make a guess on this. At pretty low f, absorbtion starts to go down. I know they communicate with submarines with RF carriers around 12-14 kc because ocean water is almost transparent. Only when absorption of RF gets high then there are "bioeffects" (mostly thermal, but there is controversy about non-thermal effects). Others here might be able to be more specific for that range 14 khz to 300 khz. > Thanks, > -Chris > > -- > /> Christopher Cole <\ <\ > << Cole Design and Development \\ email: cole@coledd.com \\ > \\ Computer Networking & Embedded Electronics \\ web: http://coledd.com >> > \> \> Article: 97885 of rec.radio.amateur.homebrew From: hikezilla@yahoo.com Subject: Parts for Sale Date: 5 Jul 2006 10:27:13 -0700 Message-ID: <1152120433.359568.4860@a14g2000cwb.googlegroups.com> I have moved my junkbox surplus stuff to a new website. http://www.hamradparts.com 1N4148 Diodes $3.00 for 100, $4.00 for 200 1N4001 - 1 Amp 50v General Purpose Rectifier Diodes - $3.00 for 50 33pf NPO Caps, SMT 0805, 50V - $3.00 for 100 150pf NPO Caps, SMT 0805, 50V - $3.00 for 100 220pf NPO Caps, SMT 0805, 50V - $3.00 for 100 390pf Caps, SMT 1206, 50V - $3.00 for 100 1500pf NPO Caps, SMT 0805, 50V - $3.00 for 100 3300pf Caps, SMT 0805, 25V - $3.00 for 100 .1uF Caps, SMT 0805, 50V - $3.00 for 100 SPECIAL SMT PACK - 50 of each listed value $9.00 350 total parts 2N3704 NPN TO92 - 20 for $2.00 2N2907 PNP TO92 Package - $4.00 for 50 2N3904 NPN TO92 Package - $4.00 for 50 2N2222 NPN TO18 (metal) Package - 5 for $1.00 MMBT4403 PNP SMT transistor - 50 for $4.00 SPECIAL: 100pcs PN2222A Motorola $7.00- FREE SHIPPING 2N2222 NPN TO92 Package - $4.00 for 50 The 2N2222 is a bulk transistor...meaning the part is not labeled. They ship in a Zip Lock packet and the packet is clearly labeled. 2N3906 PNP TO92 Package - $4.00 for 50 The 2N3906 is a bulk transistor...meaning the part is not labeled. They ship in a Zip Lock packet and the packet is clearly labeled. IRF510 - MOSFET AMP TO220 - 4 for $5.00 Crystal Ladder Filters anyone? 3.575611 Mhz HC49 Crystals - 5 for $2.00 4.9152 Mhz HC49 Crystals - 10 for $3.00 9.830 Mhz Crystals (SS2 package) - 20 for $3.00 LM7805ACV 5v Positive Voltage Regulators (TO220) 5 for $2.00 LM386N-1 - Audio Amp 6 for $5.00 Sticky Back Rubber Feet for your projects, self adhesive - 8 to a strip - 2 Strips for $1.00 Panasonic Wall Warts - 12VDC, 500mA (center negative) $6.00 each If you need center positiove, cut off the end and reverse it. I use these to power my rock mites, my TT2, and all of my homebrew test gear. 8pf NPO Ceramic 50 for $3.00 11pf NPO Ceramic 50 for $3.00 12pf NPO Ceramic 50 for $3.00 22pf Ceramic 50 for $3.00 470pf Ceramic 50 for $3.00 560pf Ceramic 50 for $3.00 .1 uF (104J) NPO Ceramic 50 for $3.00 .01uF (103K) Ceramic 50 for $3.00 SPECIAL PACK - 25 of each listed ceramic $10.00 200 parts total Cash, check, paypal now accepted Paypal to: orders@hamradparts.com Add $3.00 shipping to any order under $50.00 unless you are ordering the special Motorola PN2222 transistors. Brian Murrey 47 Grassy Drive New Whiteland IN 46184 73 de KB9BVN Article: 97886 of rec.radio.amateur.homebrew From: hikezilla@yahoo.com Subject: Re: frequency meter Date: 5 Jul 2006 10:29:33 -0700 Message-ID: <1152120573.766175.190310@m73g2000cwd.googlegroups.com> References: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> Small Wonder Labs sells the Freq Mite for $20.00 - if you build it and put it in an Altoids tin, you'd have a nice small portable freq counter. http://www.smallwonderlabs.com 73 de KB9BVN Kirk wrote: > I have looked at used eqpt etc and kits. Most kits are partial kits. > How I wish Heath were still in business :( > > Any recommendations for a frequency meter of good accuracy. I dont need > high frequency capability - a few MHz is good enough but I need good > accuracy. > > thanks > Kirk > KC7THL Article: 97887 of rec.radio.amateur.homebrew From: "Steve N." Subject: Re: quadrature detector & SSB Date: Wed, 5 Jul 2006 14:27:08 -0500 Message-ID: References: "MAc" wrote in message news:e8d6bk$s6n$1@news.onet.pl... > How to use quadrature detector to demodulate cw and ssb. I want to use > AD607 in simple project. There is Quadrature detector on "the end" with > two outputs I&Q - and internal phase shifter. How to detest SSB simplest > way? > > 73 > > mac With all that... AD607 does NOT have a "quadrature detector". It has an "I & Q demodulator". BIG difference. You must read the datasheet and app notes to use it correctly. It is capable of demudulating many types of modulation. [typo accepted] 73, Steve, K9DCI Article: 97888 of rec.radio.amateur.homebrew From: "Steve N." Subject: Re: frequency meter Date: Wed, 5 Jul 2006 14:49:00 -0500 Message-ID: References: <1151976452.561672.72470@j8g2000cwa.googlegroups.com> "Kirk" wrote in message news:1151976452.561672.72470@j8g2000cwa.googlegroups.com... > I have looked at used eqpt etc and kits. Most kits are partial kits. > How I wish Heath were still in business :( > > Any recommendations for a frequency meter of good accuracy. I dont need > high frequency capability - a few MHz is good enough but I need good > accuracy. > > thanks > Kirk > KC7THL > You need to be more specific. There are "frequency counters" (common) that are different from "frequency meters" (older equipment and more rare). How many is a "few MHz." What is "good accuracy" ? What are you measuring ? What is your price range ? If a Heath frequency counter will do, then any frequency counter available will probably do. Elenco has small counters that start at $150 http://www.elenco.com/ Similar small units: http://www.optoelectronics.com/cub.htm http://www.apogeekits.com/frequency_counter.htm 73, Steve, K9DCI Not sure what you mean by partial kit, but: http://www.piclist.com/techref/piclist/weedfreq.htm ~ $49 73, Steve, K9DCI Article: 97889 of rec.radio.amateur.homebrew From: MAc Subject: Re: quadrature detector & SSB Date: Wed, 05 Jul 2006 23:05:30 +0200 Message-ID: References: Steve N. napisa³(a): > AD607 does NOT have a "quadrature detector". It has an "I & Q demodulator". > BIG difference. You must read the datasheet and app notes to use it > correctly. It is capable of demudulating many types of modulation. [typo > accepted] My mistake, I undersand. But datasheet says nothing more exept "it is possible to detect ssb with ad607" Thanks MAc Article: 97890 of rec.radio.amateur.homebrew From: "AndyS" Subject: Re: IEEE Standard for RF Safety Levels Date: 5 Jul 2006 15:48:30 -0700 Message-ID: <1152139710.519301.317210@a14g2000cwb.googlegroups.com> References: Christopher Cole wrote: > > There is a nice chart for MPE limits. However, there is no information given > for frequencies below 300kHz. Does anyone know what the MPE limits would > be for both electric and magnetic field strength at 80kHz? > > Thanks, > \> ))))) Andy in Eureka, Texas W4OAH\ ( The chart is small, and my glasses are thick, so I apologize for any lack of precision.... ) Article: 97891 of rec.radio.amateur.homebrew Date: Wed, 05 Jul 2006 16:55:32 -0700 From: Tim Wescott Subject: Re: quadrature detector & SSB References: Message-ID: MAc wrote: > Steve N. napisa³(a): > >> AD607 does NOT have a "quadrature detector". It has an "I & Q >> demodulator". >> BIG difference. You must read the datasheet and app notes to use it >> correctly. It is capable of demudulating many types of modulation. >> [typo >> accepted] > > > My mistake, I undersand. But datasheet says nothing more exept "it is > possible to detect ssb with ad607" > > Thanks > MAc Do a search on the phasing method of SSB reception, then the "Weaver" method. Either of those should get you a block diagram showing what to do with the I and Q outputs. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Posting from Google? See http://cfaj.freeshell.org/google/ "Applied Control Theory for Embedded Systems" came out in April. See details at http://www.wescottdesign.com/actfes/actfes.html Article: 97892 of rec.radio.amateur.homebrew From: "Kirk" Subject: Re: Garage hamshacks? Here is my garage "secret lab"... Date: 5 Jul 2006 17:57:22 -0700 Message-ID: <1152147442.917448.256100@m73g2000cwd.googlegroups.com> References: A thermometer is the only safe way to know how much it is heating the garage. It is not how many days a week you do this that is dangerous - it is the peak temperature. Pressure in the system is a function of condenser temperature and the manufacturer often doesnt design beyond 110F as tubing isnt free (heat exchanger) nor fan horsepower(plus most weather is below 110 except in a few places). Excessive pressure increases the run current on the pump (compressor) which is cooled by refrigerant flow. As temperature rises on the air to the condenser heat in the system also increases due to higher run current so it stacks up fast. The higher EER units have more heat exchanger and are a bit more tolerant. Straydog wrote: > (FYI/FWIW) > > Recently there were a lot of comments on using a garage as a hamshack. > > My problem was not the hamshack, but where to build my "retro" tube-based > ham gear (HF) and my garage gets cold in the winter (30s F and below at > worst) and too hot (90 F) and humid in the summer. So I decided to build a > "cubicle" out of plywood (5/8" for me, leftover from a hurricane passby > that I used to cover our most expensive windows). So I had these pieces of > 4' x 6' that I put together to make a cubicle 6' high, 4' wide, and 8' > deep, and put in a 18" wide "bench" (made out of a piece of lam pine about > 6-7' long. This gets the drill noises, the soldering smoke, and all the > little metal shavings, drillings, file dust, etc., out of the house and > away from our rugs and somewhere where I don't have to be constantly > cleaning it up. > > For the winter, a standard electric space heater easily warms up the > inside in less than 1/2 hour, and in the summer, a small A/C cools it off > in minutes. The A/C vents the hot air into the garage but it does not seem > to warm up the garage much beyond what it warms up in normal hot weather > (I mention this because the warranty says it will be voided if you do > this, but I'm only doing this once a week all, or as much of the day, as > possible). On the A/C, many will collect significant amounts of condensed > water and then excess will drip out on the "outside" but I've found in > such a small cubicle that running the A/C for many hours does not cause > significant amounts of water to accumulate and perhaps this is due to the > small volume of the cubicle and once it is dehumidified, not much new > water vapor enters over a whole afternoon or more. I mention this because > I was concerned about having a constant drip of water onto the garage > floor. This has not happened yet (not a drop has come out). > > For anyone who wants to see images of this cubicle (for building stuff), > they along with images of some of my homebrew gear, kludge-ugly-all-from- > the-junkbox, can be found at: > > http://www.panix.com/~asd > > Just look for the links to the "secret lab" and click on them. > > FYI/FWIW: The rest of that index page lists the done projects and the in > progress projects (as well as pics of prior rigs of mostly commercial gear > I've had during most of my ham career). > > 73 > Art, W4PON Article: 97893 of rec.radio.amateur.homebrew From: David Subject: Matching SA602 mixer to SA605 Message-ID: Date: Thu, 06 Jul 2006 10:13:07 GMT I am looking for a reasonably efficient method of coupling a 602 mixer output to a 605 input at 45MHz. I have tried a tuned circuit with coupling caps and did not get good results. Both the 602 and 605 are working fine independently. (I tested the 605 with a match up from 50 Ohms to 1k5). I am wanting a receiver with around 10dB signal to noise ratio at -115 to -118dBm. Signal frequency is 151 MHz. 1st IF is 45MHz, 2nd IF is 455kHz(+/-15 kHz bandwidth). The input filter has a bandwidth of 6MHz. The image should not be an issue as it is way down at 60MHz. I don't want to loose much gain between the 602 and 605 (about 3-5dB would be acceptable). Thanks in advance Regards David Article: 97894 of rec.radio.amateur.homebrew From: "W3JDR" References: Subject: Re: Matching SA602 mixer to SA605 Message-ID: Date: Thu, 06 Jul 2006 10:38:19 GMT > I have tried a tuned circuit with coupling caps and did not get good > results. ----------- David, "...did not get good results" is a very fuzzy description of the problem you encountered. Can you be more specific?. Is the problem a sensitivity problem? Why do you think it's an interstage coupling issue? You don't say whether you're coupling from the '602's mixer output into the '605's mixer input, or from the '602's mixer output into the '605's IF input. In the former case, the 605's input resistance is in the 4.5K range while in the latter case the input resistances is about 1.5K. The '602 output resistance is also in the 1.5K range. In either case the output/input resistances are already close enough to be within a few dB of optimum with just a DC blocking cap for coupling (assuming the interface is resonant). I don't know why you weren't successful in just resonating the output of the '602 and capacitively coupling into the '605 with a large coupling cap. Can you tell us what values you used? Without analyzing this in detail, I'd say that if your interstage coupling is resonant and tight (large coupling cap), then your sensitivity performance will probably be limited by the noise figures of the two mixers in cascade (assuming that the tuned input circuit isn't real lossy). Joe W3JDR "David" wrote in message news:Tm5rg.412$tE5.236@news-server.bigpond.net.au... >I am looking for a reasonably efficient method of coupling a 602 mixer >output to a 605 input at 45MHz. > > I have tried a tuned circuit with coupling caps and did not get good > results. Both the 602 and 605 are working fine independently. (I tested > the 605 with a match up from 50 Ohms to 1k5). > > I am wanting a receiver with around 10dB signal to noise ratio at -115 > to -118dBm. > Signal frequency is 151 MHz. > 1st IF is 45MHz, 2nd IF is 455kHz(+/-15 kHz bandwidth). > The input filter has a bandwidth of 6MHz. > The image should not be an issue as it is way down at 60MHz. > > I don't want to loose much gain between the 602 and 605 (about 3-5dB would > be acceptable). > > Thanks in advance > > Regards > > David Article: 97895 of rec.radio.amateur.homebrew From: john carson Subject: need part Message-ID: Date: Thu, 06 Jul 2006 19:10:08 GMT Hello group --- What is replacement for Toshiba K2746 transistor. John Article: 97896 of rec.radio.amateur.homebrew From: "Eamon Skelton" Subject: Re: need part References: Message-ID: Date: Thu, 06 Jul 2006 20:26:32 GMT On Thu, 06 Jul 2006 19:10:08 +0000, john carson wrote: > Hello group --- What is replacement for Toshiba K2746 transistor. John Most likely it is a 2SK2746 MOSFET. The datasheet might give you some clues: http://www.semicon.toshiba.co.jp/docget.jsp?pid=2SK2746&lang=en&type=datasheet 73, Ed. EI9GQ. -- Remove 'X' to replay by e-mail. Linux 2.6.17 Article: 97897 of rec.radio.amateur.homebrew From: dplatt@radagast.org (Dave Platt) Subject: Re: need part Date: Thu, 06 Jul 2006 20:32:24 -0000 Message-ID: <12aqsqo85p4lc6e@corp.supernews.com> References: In article , john carson wrote: >Hello group --- What is replacement for Toshiba K2746 transistor. John It's almost certainly a 2SK2746: "Silicon N-channel MOS type field effect transistor for high speed, high current switching, DC-DC converter and motor drive applications" according to the info at www.datasheetarchive.com. Maximum ratings are 800 volts, 7 amps DC, 21 amps pulse, 30 volts on the gate, 150 watts dissipation. http://www.mark5.co.uk/ seems to have some in stock, but the prices seem high. DigiKey carries the 2SK2746 but it looks as if they don't care to sell them in quantities less than 3000 pieces, special-order only. It looks to me as if an International Rectifier IRFPE50 might quality as a substitute (same voltage rating, same threshold-voltage range, slightly better Rds(on), Id, and Pd ratings) - DigiKey has these in stock for under $7 each. One site suggests the SSM09N70F as a substitute. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 97898 of rec.radio.amateur.homebrew From: "jack" Subject: Some GHz hacking Date: Fri, 7 Jul 2006 09:13:17 -0400 Message-ID: <0ZCdnenIUNdPKTDZnZ2dnUVZ_tCdnZ2d@comcast.com> pointed out to me by one of "my three sons" -- i could never get any of them to pick up Morse: http://www.drivebywifiguide.com/TetraBrikHowTo.htm Article: 97899 of rec.radio.amateur.homebrew From: "Joel Kolstad" Subject: Re: Some GHz hacking Date: Thu, 6 Jul 2006 20:01:20 -0700 Message-ID: <12arjk1c36rl83c@corp.supernews.com> References: <0ZCdnenIUNdPKTDZnZ2dnUVZ_tCdnZ2d@comcast.com> "jack" wrote in message news:0ZCdnenIUNdPKTDZnZ2dnUVZ_tCdnZ2d@comcast.com... > http://www.drivebywifiguide.com/TetraBrikHowTo.htm I'm leery of anyone selling an antenna (or a book of how to build antennas, in this case) that doesn't even measure return loss... Article: 97900 of rec.radio.amateur.homebrew From: "Pete KE9OA" References: <1152029909.830687.271940@m79g2000cwm.googlegroups.com> Subject: Re: quadrature detector & SSB Date: Thu, 6 Jul 2006 23:51:59 -0500 Message-ID: <_KydndkeM5n0dTDZnZ2dnUVZ_uidnZ2d@comcast.com> I never tried to use this chip as an SSB detector, but I did design an AM sync detector a couple of years back. I remember that I had to limit the input level to around 30uV when used in the fashion, but it wasn't bad for that purpose. Pete "MAc" wrote in message news:e8e4t7$7v7$1@news.onet.pl... > AndyS wrote: > > A Quadrature detector is normally used only for FM demodulation. > > Yes. > > but (from Analog Devices): > "...Applications of the AD607 include narrowband systems with a high first > IF (21.4 MHz to 300 MHz) and a second IF at 10.7 MHz, 455 kHz, or 450 kHz. > These include Dual Conversion IS136, GSM, TETRA, and MSAT Receivers; and > Single or Dual Conversion VHF and HF AM, SSB, CW, or QPSK Receivers... " > > But :-) I did not find any SSB application :-( So I need an example. > > > > Just my two cents worth.... If anyone disagrees, I'd be happy to >> learn from them where my explanation is wrong..... but I warn you, >> it ain't far wrong.... cause it worked for me for many many years >> in designing receivers for both commercial and military products >> ...:>))))) > > > Andy Thanks for your cents, rather dollars. > > PS there is internal quadrature pll in ad607. > > MAc