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On Wed, 09 Jul 2003 19:30:37 -0700, Frank Gilliland
wrote: Lou Franklin can help! Pay him money and he will help you to violate federal regulations! But don't ask him to help you pay the fines...LOL! While he certainly can help you break a number of federal regulations, he also offers some things which "appear" to provide a legal performance boost. I don't have the background or education to know if these things are the CB equivalent of snake oil, or if they really work. I would appreciate the comments of the many technically proficient members of this newsgroup. In particular, I'm looking at the plans for his CP beam antenna and the Digital Speech Processor kit. I have the skills required to construct either, but not the knowledge to know if either project is worth the effort. Your advice and guidance would be appreciated. Thanks, Earl Johnston |
#2
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In , Earl Johnston
wrote: On Wed, 09 Jul 2003 19:30:37 -0700, Frank Gilliland wrote: Lou Franklin can help! Pay him money and he will help you to violate federal regulations! But don't ask him to help you pay the fines...LOL! While he certainly can help you break a number of federal regulations, he also offers some things which "appear" to provide a legal performance boost. I don't have the background or education to know if these things are the CB equivalent of snake oil, or if they really work. I would appreciate the comments of the many technically proficient members of this newsgroup. In particular, I'm looking at the plans for his CP beam antenna Circular polarization of a signal is caused by "Faraday rotation" as a signal passes through the upper atmosphere, and occurs mainly with frequencies from 100 to 1000 MHz. Unless you plan on tuning in on satellites in that frequency range, an antenna designed for circular polarization isn't going to do much good. IOW, the term was probably adopted into CB mythology to describe a helical antenna, which is no more efficient than any fiberglass stick antenna, and less efficient than an unloaded whip. Nearly all CB radio antennas are vertical, and therefore vertically polarized. You are wasting your resources trying to make an antenna that's capable of receiving both vertical and horizontal polarization. For lots of antenna information, here's a good place to start: http://www.ac6v.com/antprojects.htm and the Digital Speech Processor kit. I have the skills required to construct either, but not the knowledge to know if either project is worth the effort. A speech processor is an excellent idea, but I have no idea if Lou's even works. I certainly have some misgivings about 90% average modulation! But since you have some electronic skills, check this out: www.epanorama.net ============= "...but I admitted I was wrong, Like a man! Something you and QRM have a problem with. You guys are wrong and you both know it and are both too small to admit it." ---- Twistedhed ---- ============= -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- |
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#5
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On Thu, 10 Jul 2003 07:16:18 -0700, Frank Gilliland
wrote: Circular polarization of a signal is caused by "Faraday rotation" as a signal passes through the upper atmosphere, and occurs mainly with frequencies from 100 to 1000 MHz. Unless you plan on tuning in on satellites in that frequency range, an antenna designed for circular polarization isn't going to do much good. IOW, the term was probably adopted into CB mythology to describe a helical antenna, which is no more efficient than any fiberglass stick antenna, and less efficient than an unloaded whip. Nearly all CB radio antennas are vertical, and therefore vertically polarized. You are wasting your resources trying to make an antenna that's capable of receiving both vertical and horizontal polarization. For lots of antenna information, here's a good place to start: http://www.ac6v.com/antprojects.htm Thank you for the advice, and there is a L-O-T of information at that site. The circular polarized beam antenna idea is not unique to Lou Franklin. I have seen the same concept promoted by Jo Gunn Antennas "V Series (DX Antennas) - The V Antennas have a single feed line which transmits circular polarity. This is the most effective way to talk DX and hold the conditions the longest. For CB'er who wants to get the most out of his skip talking, the V's will give the best performance possible." http://www.jogunn.com/jgwhich.htm I had the impression that the Jo Gunn antennas were quality products with solid design. I understand that for those of you in the United States, CB is restricted to ground wave communication. However, others in this forum are able to talk skip without running afoul of our national regulations. Leaving aside the question of whether or not one should talk skip on CB, Are Lou Franklin and Jo Gunn Antennas just blowing smoke, or is there anything in their claims that CP beams are best for skip talking? |
#6
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In , Earl Johnston
wrote: On Thu, 10 Jul 2003 07:16:18 -0700, Frank Gilliland wrote: Circular polarization of a signal is caused by "Faraday rotation" as a signal passes through the upper atmosphere, and occurs mainly with frequencies from 100 to 1000 MHz. Unless you plan on tuning in on satellites in that frequency range, an antenna designed for circular polarization isn't going to do much good. IOW, the term was probably adopted into CB mythology to describe a helical antenna, which is no more efficient than any fiberglass stick antenna, and less efficient than an unloaded whip. Nearly all CB radio antennas are vertical, and therefore vertically polarized. You are wasting your resources trying to make an antenna that's capable of receiving both vertical and horizontal polarization. For lots of antenna information, here's a good place to start: http://www.ac6v.com/antprojects.htm Thank you for the advice, and there is a L-O-T of information at that site. The circular polarized beam antenna idea is not unique to Lou Franklin. I have seen the same concept promoted by Jo Gunn Antennas "V Series (DX Antennas) - The V Antennas have a single feed line which transmits circular polarity. This is the most effective way to talk DX and hold the conditions the longest. For CB'er who wants to get the most out of his skip talking, the V's will give the best performance possible." http://www.jogunn.com/jgwhich.htm I had the impression that the Jo Gunn antennas were quality products with solid design. I understand that for those of you in the United States, CB is restricted to ground wave communication. However, others in this forum are able to talk skip without running afoul of our national regulations. Leaving aside the question of whether or not one should talk skip on CB, Are Lou Franklin and Jo Gunn Antennas just blowing smoke, or is there anything in their claims that CP beams are best for skip talking? Smoke city. It takes a helical antenna to radiate circular polarization. Those fiberglass CB antennas are called 'helical' only because of how they are made, not because they radiate circular polarization (which they don't). Want to see a true helical antenna? http://www.cc.edu/physics/radtel01.html That's 30 inches long for 2400 MHz -- now can you imagine the size of a helical for 27 MHz? The Jo Gunn antenna you cited is called a V-yagi, and is just another variation of the basic yagi design. Assuming it is mounted horizontally, it's polarity is horizontal, not circular. Here's a couple more links on antennas that I should have posted first: http://www.tmeg.com/tutorials/antennas/antennas.htm http://www.cebik.com "The more we understand, the better our choices will be." -- L. B. Cebik, W4RNL -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- |
#7
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Frank Gilliland wrote in message . ..
In , Earl Johnston wrote: On Wed, 09 Jul 2003 19:30:37 -0700, Frank Gilliland wrote: Lou Franklin can help! Pay him money and he will help you to violate federal regulations! But don't ask him to help you pay the fines...LOL! While he certainly can help you break a number of federal regulations, he also offers some things which "appear" to provide a legal performance boost. I don't have the background or education to know if these things are the CB equivalent of snake oil, or if they really work. I would appreciate the comments of the many technically proficient members of this newsgroup. In particular, I'm looking at the plans for his CP beam antenna Circular polarization of a signal is caused by "Faraday rotation" as a signal passes through the upper atmosphere, and occurs mainly with frequencies from 100 to 1000 MHz. Unless you plan on tuning in on satellites in that frequency range, an antenna designed for circular polarization isn't going to do much good. IOW, the term was probably adopted into CB mythology to describe a helical antenna, which is no more efficient than any fiberglass stick antenna, and less efficient than an unloaded whip. Nearly all CB radio antennas are vertical, and therefore vertically polarized. You are wasting your resources trying to make an antenna that's capable of receiving both vertical and horizontal polarization. For lots of antenna information, here's a good place to start: I'd like to be there when you tell that to Avanti, makers of the PDL-II and Moonraker series of antennas, which feature selectable horizontal and vertical polarization! I think they would laugh at you, Frankie, as will the many owners of those antennas. http://www.ac6v.com/antprojects.htm and the Digital Speech Processor kit. I have the skills required to construct either, but not the knowledge to know if either project is worth the effort. A speech processor is an excellent idea, but I have no idea if Lou's even works. I certainly have some misgivings about 90% average modulation! What? A "commercial broadcast engineer" that can't look at a schematic and know whether the circuit works as advertised or not? "90% average modulation" would be great on AM (ask a real commercial radio engineer, Frankie; they use 'em all the time), but when the operator isn't saying anything there'd be a rather obnoxious noise transmitted as the circuit searches for anything to keep the modulation at 90%. As witness the BBC some years ago, until they learned to turn down the processing. But why don't you know this IF you're really a commercial broadcast engineer as you claimed? |
#8
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In ,
(Richard Cranium) wrote: Frank Gilliland wrote in message . .. In , Earl Johnston wrote: On Wed, 09 Jul 2003 19:30:37 -0700, Frank Gilliland wrote: Lou Franklin can help! Pay him money and he will help you to violate federal regulations! But don't ask him to help you pay the fines...LOL! While he certainly can help you break a number of federal regulations, he also offers some things which "appear" to provide a legal performance boost. I don't have the background or education to know if these things are the CB equivalent of snake oil, or if they really work. I would appreciate the comments of the many technically proficient members of this newsgroup. In particular, I'm looking at the plans for his CP beam antenna Circular polarization of a signal is caused by "Faraday rotation" as a signal passes through the upper atmosphere, and occurs mainly with frequencies from 100 to 1000 MHz. Unless you plan on tuning in on satellites in that frequency range, an antenna designed for circular polarization isn't going to do much good. IOW, the term was probably adopted into CB mythology to describe a helical antenna, which is no more efficient than any fiberglass stick antenna, and less efficient than an unloaded whip. Nearly all CB radio antennas are vertical, and therefore vertically polarized. You are wasting your resources trying to make an antenna that's capable of receiving both vertical and horizontal polarization. For lots of antenna information, here's a good place to start: I'd like to be there when you tell that to Avanti, makers of the PDL-II and Moonraker series of antennas, which feature selectable horizontal and vertical polarization! I think they would laugh at you, Frankie, as will the many owners of those antennas. I would like you to be there, too. And who knows -- if you can keep your mouth shut and your mind open you might actually learn something. http://www.ac6v.com/antprojects.htm and the Digital Speech Processor kit. I have the skills required to construct either, but not the knowledge to know if either project is worth the effort. A speech processor is an excellent idea, but I have no idea if Lou's even works. I certainly have some misgivings about 90% average modulation! What? A "commercial broadcast engineer" that can't look at a schematic and know whether the circuit works as advertised or not? Not when you have four high-gain, high input-Z OP-amps on the same chip, all inverting, all DC isolated on both the inputs and outputs, and all outputs are unloaded. IOW, any one of them could start oscillating at any time. Or, like I said, the thing may not even work at all because it might lock up on power up. As far as the "processing" is concerned, it's nothing more than a clipper. The whole thing can be done much more easily with a few discretes, and I would certainly have much more confidence in the circuit. "90% average modulation" would be great on AM (ask a real commercial radio engineer, Frankie; they use 'em all the time), Considering that the circuit is nothing more than a preamp and clipper, I have no idea where he gets the idea that it will achieve 90% average modulation. And in case you missed class, any form of compression and/or clipping is a form of distortion; i.e, more compression equals more distortion. Years ago, some AM broadcast stations would crank up the compression to the point where the sound quality was offensive, but that's rarely done anymore. but when the operator isn't saying anything there'd be a rather obnoxious noise transmitted as the circuit searches for anything to keep the modulation at 90%. As witness the BBC some years ago, until they learned to turn down the processing. You are professing your ignorance yet again -- noise gates have been around almost as long as compression. And for your information, compressors and gates are considered ancient technology in broadcasting these days, because with the newer digital audio processors you can tailor your response curve to just about shape you want in less than a minute via software. But why don't you know this IF you're really a commercial broadcast engineer as you claimed? *-plonk-* -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- |
#9
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On Mon, 14 Jul 2003 00:22:56 -0700, Frank Gilliland
wrote: Leaving aside the question of whether or not one should talk skip on CB, Are Lou Franklin and Jo Gunn Antennas just blowing smoke, or is there anything in their claims that CP beams are best for skip talking? Smoke city. It takes a helical antenna to radiate circular polarization. Those fiberglass CB antennas are called 'helical' only because of how they are made, not because they radiate circular polarization (which they don't). Thank you. Appreaciate you taking the time to explain and provide the great links. I'm going to do a bit of study at the sites you provided. Want to see a true helical antenna? http://www.cc.edu/physics/radtel01.html That's 30 inches long for 2400 MHz -- now can you imagine the size of a helical for 27 MHz? over 200 feet The Jo Gunn antenna you cited is called a V-yagi, and is just another variation of the basic yagi design. Assuming it is mounted horizontally, it's polarity is horizontal, not circular. If it looks too good to be true, it probably is. "The more we understand, the better our choices will be." -- L. B. Cebik, W4RNL Amen to that. |
#10
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Frank Gilliland wrote in message ...
In , (Richard Cranium) wrote: I'd like to be there when you tell that to Avanti, makers of the PDL-II and Moonraker series of antennas, which feature selectable horizontal and vertical polarization! I think they would laugh at you, Frankie, as will the many owners of those antennas. I would like you to be there, too. When one of you has a time machine, let me know. I was under the impression that Avanti was no more. :~) the Digital Speech Processor kit. I have the skills required to construct either, but not the knowledge to know if either project is worth the effort. A speech processor is an excellent idea, but I have no idea if Lou's even works. I certainly have some misgivings about 90% average modulation! What? A "commercial broadcast engineer" that can't look at a schematic and know whether the circuit works as advertised or not? Not when you have four high-gain, high input-Z OP-amps on the same chip, all inverting, all DC isolated on both the inputs and outputs, and all outputs are unloaded. Digital speech processor? I have details of his "DSP" - Dynamic Speech Processor, which makes claims about a 90% average... so seems to be what is being referring to above. Looking at the diagram, the first amp is a buffer stage, the second has a gain of about 45 and the third a gain of about 21. From his figures for a standard mic output, a loud whistle should produce about 6 volts into the clipper... which is down to 500mV from the clipper into the output amp. IOW, any one of them could start oscillating at any time. I assume that you do not have a copy of Lou's guide to the DSP... quote you may get self oscillation (squealing) due to the overall high gain of the combined DSP, power mike (if used), and radio circuits /quote And... quote The squeal problem is very common in newer Uniden SSB rigs /quote His "cop-out" is that with "correct adjustment", this should not happen. But, he is putting this adjustment in the hands of people who he has said cannot even solder correctly. And how can anyone adjust it correctly with, as he suggests, an SWR/power meter or someone listening to your signal? Or, like I said, the thing may not even work at all because it might lock up on power up. More likely, it will fail due to poor building of the circuit. I had someone ask me to fit one for him, which he supplied as supplied by the shop, ready made. There were all kinds of problems, including the screened wires not being correctly connected - they were shorted between screen and inner wire. Also, the version I have the details for had the LM324 fitted in place of the LM3900. It should be noted that the LM324 is a "domestic" spec chip... and may fail in temperatures below Zero or above +70° centigrade. The LM2902 (-40° to +85°) or LM124 (-55 to +125°) are better. "90% average modulation" would be great on AM (ask a real commercial radio engineer, Frankie; they use 'em all the time), Considering that the circuit is nothing more than a preamp and clipper, I have no idea where he gets the idea that it will achieve 90% average modulation. Does he claim that *the DSP* will manage that magical 90%, or just that the figure is possible? quote With correct speech processing, it is possible to increase the average modulation to about 90%! /quote Unless someone has seen a statement claiming that his product does that "90%", or that the "90%" can be done without unacceptable distortion or harmonic content... then it is nothing but sales bumf- careful wording. Also, it says, "about 90%". However, here is another of quote from Lou: quote Up to 15dB of clipping is quite acceptable to the ear /quote The average peak to average ratio figure for the human voice is 14dB, although some people may be higher or lower. The 90% quoted may be for some people with a lower than average ratio. Even then, to get such a high average, without an unacceptable level of distortion, would be pretty tight... and certainly not possible without using proper test equipment to adjust the device exactly. in case you missed class, any form of compression and/or clipping is a form of distortion; i.e, more compression equals more distortion. Certainly with clipping, but how about a VOGAD? If it is set to reasonable attack and decay times, there should be no problem. However, the time delay means that it would not work the same as clipping. Years ago, some AM broadcast stations would crank up the compression to the point where the sound quality was offensive, but that's rarely done anymore. In the UK, Radio1 manages to create "offensive" audio without adding distortion... they just play crap "music". ;~) but when the operator isn't saying anything there'd be a rather obnoxious noise transmitted as the circuit searches for anything to keep the modulation at 90%. As witness the BBC some years ago, until they learned to turn down the processing. The "searching for noise" will probably be associated with something more complicated than the simple amp and clipper used in the DSP... possibly a combination of VOGAD and clipping. Brainbuster. |
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