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On Thu, 07 Apr 2005 19:32:22 -0400, jim wrote:
Vinnie S. wrote: On Thu, 07 Apr 2005 22:18:01 GMT, Lancer wrote: Why are you so dead set against building an antenna? Actually, I am not. Just not right now. I just want to get on the air, as soon as possible, hopefully by the end of April. I just got into this hobby, and have barely been in it a month. Most of it just studying code and Tech books. I didn't even study for General, but passed it anyway. I failed the extra. I plan on getting into the hobby full blast, and am interested in QRP. I know little about that. I kind of like the idea of lower power DX. It will feel like when you were a kid, talking to a CB station on a toy walkie talkie. I think QRP require home brews. But as I said, I just want to get on the air. At least to learn the lingo a bit. My mind was kind of fried from the studying, so I want actually hands on. Once I can master that, we'll go the next step. Vinnie S. Nothing for nothing Vinnie but if you got your ticket why are you asking questions concerning amateur matters in the cb forum? Granted there are some very knowlegable folks here but did you try any other usenet groups? I didn't. I asked about the Imax and the ground plane. Both are CB questions. The only time I asked about a dipole, was to run one in my attic, for my CB. And that led to the Firestik in the attic. I haven't asked a ham question since I asked about the test info. I didn't ask a question about the ham dipole. I just said I ws waiting on getting one so I didn't have to dig 2 trenches. I know plenty of hams to ask question on the ham antennas. But none of them are on CB, nor familiar with the Imax. Vinnie S. |
On 07 Apr 2005 23:32:45 GMT, Steveo wrote in
: snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On Thu, 07 Apr 2005 19:37:07 -0400, Vinnie S.
wrote in : snip I know plenty of hams to ask question on the ham antennas. But none of them are on CB, nor familiar with the Imax. That should have been your first clue. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
Frank Gilliland wrote:
On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe |
Frank Gilliland wrote:
On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... Dang..sounds like you have a bulls-eye painted on you. All you need now is an ambulance chaser attorney to ride along with you. j/k :) |
jim wrote:
Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Ha! I knew one of those that drove her Bud van right thru the front of a shot and beer bar. Too much sampling the product. |
Steveo wrote:
jim wrote: Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Ha! I knew one of those that drove her Bud van right thru the front of a shot and beer bar. Too much sampling the product. hey bud so bristol was almost a wash with all the rain eh? good race. |
jim wrote:
Steveo wrote: jim wrote: Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Ha! I knew one of those that drove her Bud van right thru the front of a shot and beer bar. Too much sampling the product. hey bud so bristol was almost a wash with all the rain eh? good race. Yea, Saturday was downright miserable, it went down below freezing at night too but the furnace did the trick. That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. That place is killer! |
Steveo wrote:
jim wrote: Steveo wrote: jim wrote: Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Ha! I knew one of those that drove her Bud van right thru the front of a shot and beer bar. Too much sampling the product. hey bud so bristol was almost a wash with all the rain eh? good race. Yea, Saturday was downright miserable, it went down below freezing at night too but the furnace did the trick. That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. That place is killer! lets see, you drove from ohio and went through the verginnies? beautiful country that part of the us of a... |
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"Steveo" wrote in message ... jim wrote: Steveo wrote: jim wrote: Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Must have been a lot of beer or a very minor ding. Ha! I knew one of those that drove her Bud van right thru the front of a shot and beer bar. Too much sampling the product. hey bud so bristol was almost a wash with all the rain eh? good race. Yea, Saturday was downright miserable, it went down below freezing at night too but the furnace did the trick. I know how you feel Mopar. I was in Arizona a few weeks back, off roading north of Phoenix and it rained all day Saturday. Muddy as hell, still cleaning that crap off the Bronco. That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. 14 hour drive to and from for one of the guys that lives local to me. I had my Bronco trucked down, then flew, much easier. That place is killer! Sounds like it, glad you had fun. Landshark -- Most true happiness comes from one's inner life, from the disposition of the mind and soul. Admittedly, a good inner life is hard to achieve, especially in these trying times. It takes reflection and contemplation and self-discipline. |
On Thu, 07 Apr 2005 17:34:18 -0400, Vinnie S.
wrote: On Thu, 07 Apr 2005 08:53:34 -0400, Dave Hall wrote: My hat's off to Vinnie for trying to at least swing the discussions back to radio related topics, as opposed to the sniping and bickering over politics and who's gay. Totally ****ing amazing. I ask a CB antenna question is a CB newsgroup, the the ****ing demons come out. Well, I am glad about one thing. People here are finally getting to see who he assholes are. The silent majority have known for a long time. Dave "Sandbagger" |
On Thu, 07 Apr 2005 16:44:59 -0700, Frank Gilliland
wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. There's something cosmic about that. I've had 2 major accidents in my whole life, and both were in the same car. Neither were my fault. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Thu, 07 Apr 2005 15:52:43 -0700, Frank Gilliland
wrote: On Thu, 07 Apr 2005 18:48:31 -0400, Vinnie S. wrote in : On Thu, 07 Apr 2005 22:41:39 GMT, Lancer wrote: Nope. And I was in Bethlehem today. And I am in Allentown quite often. I cover the eastern part of PA. But he is **** to me. He means nothing in my life. I won't go look for him, and waste my time. He issued the the challenge. I never issued an challenge to meet him. He came on this board, and put his challenge on the archive, and said he was going to take pictures of my antennas, and post them. There is no way he can do that, the way my property is laid out. He would physically have to go onto my property. And once he does that he is fair game. And since all this is in black and white, and I know his call sign, the FCC has the evidence they need. Believe me. I have nothing to worry about. Vinnie S. You don't believe his callsign is WA3MOJ do you? I don't know what to believe from him. But if some lardass steps foot on my property, I will look thru his wallet for ID will I hold his face in the dirt. And if he doesn't have a wallet, then I will get the info from the car. .....oh brother, he's a crybaby -and- a tough-guy. This is just too good to be true! Maybe he is a true tough guy. Stranger things have happened. Dave "Sandbagger" |
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On Thu, 07 Apr 2005 13:07:20 -0700, Frank Gilliland
wrote: On Thu, 07 Apr 2005 09:05:25 -0400, Dave Hall wrote in : On Tue, 05 Apr 2005 14:26:18 -0700, Frank Gilliland wrote: On Tue, 05 Apr 2005 14:41:07 -0400, Vinnie S. wrote in : snip Should I return it? Probably. If you want a decent antenna that you can use for both CB -and- ham you should check out that link for the $4 cheapie (that I provided in a post without insult). It will probably cost -you- about $20 more because it requires a tuner which you probably don't have. The idea is to just throw a couple wires in the trees and load them up with the tuner -- that's it. It works better than any Imax or Antron, it can be used for whatever power and spectrum is handled by the tuner (usually 2-30 MHz), you can change the antenna at any time, you don't have to worry about SWR, it's cheap, and it's so easy even a Geico customer can do it. A tuner-fed non-resonent length dipole is not the best solution for CB. Neither is an Imax. True. But the dipole solution will not be any better. It is woefully inefficient Compared to what.... a 7-el beam? Any vertical antenna with gain. and would be the wrong polarity for the majority of CB work. Doesn't matter. It gets the best of both worlds. That is, unless you are so anal that you think any dipole must be both horizontal and perfectly straight. Polarity losses are negligible for DX work, but local talk is not so forgiving. They worked well on the ham bands because most H.F contacts are DX in nature and you're relying on atmospheric propagation to do most of the work. Try to work another ham 30 miles away on the H.F bands and it is surprising how difficult it can be with those wire antennas. Maybe you had difficulty, but there are a very large number of hams -and- CBers who don't share your ineptitude. A dipole is a dipole. It has 0 db of gain, and that assumes a resonant dipole . If the dipole is non-resonant and requires a tuner to force an impedance match, it will have further losses. It won't stand a chance against a commercially produced (or home made if you are so-inclined) 5/8th wave vertical (with proper radials, not an Imax). I've done this type of antenna myself and never had any problems with local contacts -- in fact, it worked a lot better than the 9' whip on the truck. I find that very hard to believe, assuming identical height and conditions, as my own experiences prove otherwise. I ran a home brewed wire dipole on CB years ago, and used it in addition to my main 5/8th wave antenna. While the dipole worked well when the skip was running, locally, the signal from the dipole was a few "S" units less than the ground plane. With 4 watts of power, you don't get much range on a horizontal wire dipole strung in a tree. Well there's your problem, Dave -- I didn't say anything about horizontal. On the contrary, it's better if it isn't. Yea, if you're talking local. For DX, horizontal is usually better for a number of reasons, most notably a lower noise floor and better take off angle. Like I said before, just throw some wire up into the trees (or whatever tall object happens to be available). Didn't you read the link I posted? Of course. But a dipole is a basic antenna. It has no gain. A properly made purpose built CB antenna will out perform it. Let's look at this from a practical standpoint. If a non-resonant, tuner fed dipole worked so well, then why aren't all CB'ers using one? Why would people want huge 5/8th wave antennas then? Better tell Jay to forget about selling his Interceptor, since a simple non-resonant dipole will work just as well and for far less money. A non-resonant dipole has ONE big advantage. It's a compromise antenna that will work on all the HF bands. That's great if you don't have the room to put up single band antennas for each band. But like any compromise, it will not work as well as a dedicated antenna for each band. Such a compromise is usually acceptable for a ham who has 1500 watts on tap. But for a 4 watt CB'er, who needs to squeeze every watt of ERP he can for best local range, he needs a high gain efficient antenna. For ham band use, I agree with you, just not for CB. What's the name of that tech school, Dave? What's your call sign Frank? Frank, your experience with both ham and CB radio is sorely lacking. You read a few books and web sites and think you have all the answers. OTOH, I've walked the walk for the last 30+ years and have played with more antennas and equipment than I can remember. I have also been in contact with people in the know when it comes to antennas. What I know, I know through experience, and that's worth 10X what you read in any book. Dave "Sandbagger" |
"Landshark" wrote:
"Steveo" wrote in message That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. 14 hour drive to and from for one of the guys that lives local to me. I had my Bronco trucked down, then flew, much easier. Man the fuel prices suck! |
On Fri, 08 Apr 2005 13:30:51 -0400, Dave Hall wrote:
Believe me. I have nothing to worry about. Vinnie S. You don't believe his callsign is WA3MOJ do you? I don't know what to believe from him. But if some lardass steps foot on my property, I will look thru his wallet for ID will I hold his face in the dirt. And if he doesn't have a wallet, then I will get the info from the car. .....oh brother, he's a crybaby -and- a tough-guy. This is just too good to be true! And it don't look like I am the only one !!! I did a little search on you in the archives. This is precious. http://groups-beta.google.com/group/... 2f3b40d85682 Maybe he is a true tough guy. Stranger things have happened. It's a amazing what a little info you can get on a poster's history on Google, Dave. My favorite about this info on Frank, it the imaginary McDonald's, and the fishing trip he had at the lake in a storm !!!! Vinnie S. |
Lancer wrote:
On 08 Apr 2005 20:45:44 GMT, Steveo wrote: "Landshark" wrote: "Steveo" wrote in message That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. 14 hour drive to and from for one of the guys that lives local to me. I had my Bronco trucked down, then flew, much easier. Man the fuel prices suck! $2.18 here Steve... Glad my car gets almost 30 mpg... I spent about $300 in fuel round-trip to Bristol. ugh |
Lancer wrote:
On 08 Apr 2005 21:18:37 GMT, Steveo wrote: Lancer wrote: On 08 Apr 2005 20:45:44 GMT, Steveo wrote: "Landshark" wrote: "Steveo" wrote in message That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. 14 hour drive to and from for one of the guys that lives local to me. I had my Bronco trucked down, then flew, much easier. Man the fuel prices suck! $2.18 here Steve... Glad my car gets almost 30 mpg... I spent about $300 in fuel round-trip to Bristol. ugh Money isn't worth anything unless you spend it... Words to live by.. |
On 08 Apr 2005 21:18:37 GMT, Steveo wrote:
Lancer wrote: On 08 Apr 2005 20:45:44 GMT, Steveo wrote: "Landshark" wrote: "Steveo" wrote in message That's a long camper haul up and down those hills they call mountains in Virginia and W Virginia.. 14 hour drive to and from for one of the guys that lives local to me. I had my Bronco trucked down, then flew, much easier. Man the fuel prices suck! $2.18 here Steve... Glad my car gets almost 30 mpg... I spent about $300 in fuel round-trip to Bristol. ugh It's a good thing I don't have to spend money on fuel. Only on my wife's car, but not mine. Vinnie S. |
On Fri, 08 Apr 2005 13:59:47 -0400, Dave Hall
wrote in : snip Maybe you had difficulty, but there are a very large number of hams -and- CBers who don't share your ineptitude. A dipole is a dipole. It has 0 db of gain, Wrong. A 1/2-wave Hertzian dipole has a gain of roughly +3 dBi in free space. It has 0 dB when referenced to itself. and that assumes a resonant dipole . That's an assumtion -you- made, and it's also wrong: A resonant dipole can be any multiple of 1/2-wave, and has a gain that differs depending upon the length and directionality. If the dipole is non-resonant and requires a tuner to force an impedance match, it will have further losses. Wrong again. A tuner only adds insertion loss, which is usually quite small if it's built with quality components. The insertion loss is easily overcome by slightly increasing the length of the elements, which is no big deal since the antenna is already non-resonant. It won't stand a chance against a commercially produced (or home made if you are so-inclined) 5/8th wave vertical (with proper radials, not an Imax). Well guess what, Dave -- a 5/8-wave antenna is a non-resonant antenna and requires some method of impedance matching. Thank you. I've done this type of antenna myself and never had any problems with local contacts -- in fact, it worked a lot better than the 9' whip on the truck. I find that very hard to believe, assuming identical height and conditions, as my own experiences prove otherwise. Oh, the humanity..... I ran a home brewed wire dipole on CB years ago, and used it in addition to my main 5/8th wave antenna. While the dipole worked well when the skip was running, locally, the signal from the dipole was a few "S" units less than the ground plane. With 4 watts of power, you don't get much range on a horizontal wire dipole strung in a tree. Well there's your problem, Dave -- I didn't say anything about horizontal. On the contrary, it's better if it isn't. Yea, if you're talking local. For DX, horizontal is usually better for a number of reasons, most notably a lower noise floor and better take off angle. A horizontal dipole can have a wide variation in take-off angle depending on height above ground, ground resistance, proximity to other structures or objects, etc. And the noise floor may be slightly lower but that's a product of it's directivity, as compared to a vertical which is omnidirectional. A pair of phased verticals, as well as any other directional antenna or antenna array, will also have the effect of lowering the noise floor. Like I said before, just throw some wire up into the trees (or whatever tall object happens to be available). Didn't you read the link I posted? Of course. But a dipole is a basic antenna. It has no gain. Wrong again. As I said before, a 1/2-wave Hertzian dipole in free space has about 3 dB gain over an isotropic antenna; but a dipole is merely an antenna with two elements and is not limited to a 1/2-wave Hertzian configuration. Not only that, but a tuner isn't limited to dipole antennas -- they can load up a long-wire just as easily. A properly made purpose built CB antenna will out perform it. Get a clue, Dave. You're an Extra, right? What's the name of that tech school you claim to have attended? Let's look at this from a practical standpoint. If a non-resonant, tuner fed dipole worked so well, then why aren't all CB'ers using one? Why would people want huge 5/8th wave antennas then? Better tell Jay to forget about selling his Interceptor, since a simple non-resonant dipole will work just as well and for far less money. This resounds back to your argument that roger-beeps were illegal because most radios didn't include them. The problem is that a tuner requires a little skill and practice to use, which is beyond the scope of the intended purpose of the service (a plug-n-play radio service). A tuner requires readjustment when changing channels within the CB, and most CBers don't want to deal with the hassle. Regardless, there are still many CBers that do indeed use a tuner, not just with prefab antennas but also with homebrew and beverage-can hooks. And just about every CBer who runs a tube linear uses a tuner because it's built into the amp, which by itself blows big holes in your "practical" argument. Then there is the issue of the non-resonant 5/8-wave antenna..... oh, Dave, when will you learn? A non-resonant dipole has ONE big advantage. It's a compromise antenna that will work on all the HF bands. That's great if you don't have the room to put up single band antennas for each band. But like any compromise, it will not work as well as a dedicated antenna for each band. Such a compromise is usually acceptable for a ham who has 1500 watts on tap. But for a 4 watt CB'er, who needs to squeeze every watt of ERP he can for best local range, he needs a high gain efficient antenna. If that were the case then every CBer would have a 5-el yagi on a 30' mast and a 9' whip on their vehicles. For ham band use, I agree with you, just not for CB. What's the name of that tech school, Dave? What's your call sign Frank? I'm not a ham. I answered your question, now you answer mine: what's the name of your tech school, Dave? Frank, your experience with both ham and CB radio is sorely lacking. You read a few books and web sites and think you have all the answers. OTOH, I've walked the walk for the last 30+ years and have played with more antennas and equipment than I can remember. I have also been in contact with people in the know when it comes to antennas. What I know, I know through experience, and that's worth 10X what you read in any book. Which explains why your theory is severely lacking. If you took the time to actually learn why these things work and -then- applied them to your experiences, you could be the guru you think you already are. But you don't and you're not. Instead you do things backwards: you theorize about radio based on your own experience, then read only enough to validate your own conclusions whether they are right or not. Check this out, Dave: Education doesn't come from a textbook that some geek sat down and wrote just for ****s and giggles. It's a compendium of knowledge that has been collected from over a century of research, experimentation and practical experience by experts in all aspects of the field. Those experts didn't become experts simply by playing with CB radios as a hobby for 30 years. And an education doesn't include a couple textbooks, a few lectures and a test -- it also includes years of experience with the practical application of that knowledge. When you mock those that have a formal education and extensive experience in electronic communication then you mock the same people who made the television set you watch way too much, the telephone and cell-phone infrastructure that keeps this world talking, the NASA and JPL engineers who communicate with space probes billions of miles away, etc, etc, etc. While I may not have participated in any world-changing technology, I certainly have an education and the experience in the field that puts you to shame. Yet -you- try to teach -me- theory based on your education from a third-rate vocational tech school, a few years in a CB shop, and your experience in =amateur= radio. And here's the kicker: Do you have any idea where I came up with the idea to just throw a couple wires in the air and load them up with a tuner? A ham. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On Fri, 08 Apr 2005 13:28:53 -0400, Dave Hall
wrote in : On Thu, 07 Apr 2005 16:44:59 -0700, Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. There's something cosmic about that. I've had 2 major accidents in my whole life, and both were in the same car. Neither were my fault. Nothing is ever your fault, Dave. We discussed this problem in your last therapy session. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
Lancer wrote:
On Thu, 07 Apr 2005 20:03:26 -0400, jim wrote: Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. Ok, I'm stepping off the soap box now..... ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- got hit by a beer distributor saleswoman (go figure) and enjoyed the bennies of not reporting it hehehe Ok, got to ask... beer or? was on the way to a womans softball game (as i was the manager) with a female in the truck so it was beer :( |
Hey Vinnie............I can help you. The formula for a 1/4 wavelength
radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. I hope this helps. Pete "Frank Gilliland" wrote in message ... On Wed, 06 Apr 2005 20:14:16 -0400, Vinnie S. wrote in : On Wed, 06 Apr 2005 17:15:08 GMT, Lancer wrote: Why should I be nice? I -was- nice. We have had civil converstations, and I even gave him enough info to install the antenna in his attic, which apparently worked quite well. Then he stuck his finger into the political lion cage and turned into a sniveling crybaby after getting scratched. As for being a general-class amateur, there are literally hundreds of hammie websites that cover nothing but antennas, not to mention the ARRL manual. If he's so serious about radio, why beg a CB group for info on how to install a prefab antenna? J.H.F.C, how did he pass the exam without knowing a few antenna fundamentals? And if part of the hobby is to learn about radio comm, why ask a CB group for tech info when there are countless resources available for hams? Isn't anyone elmering the kid? I thought your were elmering him Frank? He really doesn't need one anyway, he buys his antennas. Even something as simple as a dipole, or sloper... Do you have a problem with that? Show me the rules on antenna requirements, please. Looks like Vinnie is going to be a General-class appliance operator. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On Sun, 10 Apr 2005 19:58:28 GMT, "Pete KE9OA"
wrote in : Hey Vinnie............I can help you. The formula for a 1/4 wavelength radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. It should be noted that these formulas are only appoximations. Actual sizes are dependent upon the conductivity and diameter of the elements, and the quantity and angle of the radials. When building a resonant antenna it's a good idea to make the elements a little long and trim to resonance. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. These are impedances for antennas in free space, and are practical only if you can mount your antenna well above the ground and away from any tall objects. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. Close. For lowest loss, the optimum characteristic impedance of coax is 76.9 ohms. 70-73 ohm coax is used as a compromise between low loss coax and coax optimized for minimization of flashover, the latter having an impedance of about 60 ohms. And while many people have many different ideas as to why 50 ohm coax is made, it is just a compromise between low-loss/low-flashover coax of 72 ohms and coax optimized for handling power (about 30 ohms, which is too lossy for practical transmission lines). On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. ......uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? I hope this helps. Pete ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On Sun, 10 Apr 2005 19:58:28 GMT, "Pete KE9OA"
wrote: Hey Vinnie............I can help you. The formula for a 1/4 wavelength radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. So far, that is what I have read. What I am going to do is this. I am going to add the 45 angled GP, simply because it is fairly cheap, and because it will be much easier to put it up now, than later. The formula you gave indicates that radials should be about 8.8 feet at 27 MHz. If these radials fair poorly, I will take Lancer's advice and build my own. For some reason, the radials are 6 feet. I don't know if they ran 9 feet of wire in there, or what. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. I won't do this. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. I hope this helps. Pete It's does help, Thanks ! I am borrowing an Autek RF analyzer to check the antenna while I am up in the tree. Most people that have purchase this antenna, say that it is tuned very well to 27.205. I should be flat up and down in CB and 10 meters for about 1 MHZ. I will follow up. Vinnie S. |
On Fri, 08 Apr 2005 17:02:43 -0400, Vinnie S.
wrote in : On Fri, 08 Apr 2005 13:30:51 -0400, Dave Hall wrote: Believe me. I have nothing to worry about. Vinnie S. You don't believe his callsign is WA3MOJ do you? I don't know what to believe from him. But if some lardass steps foot on my property, I will look thru his wallet for ID will I hold his face in the dirt. And if he doesn't have a wallet, then I will get the info from the car. .....oh brother, he's a crybaby -and- a tough-guy. This is just too good to be true! And it don't look like I am the only one !!! I did a little search on you in the archives. This is precious. http://groups-beta.google.com/group/... 2f3b40d85682 Don't you think it's time you quit with the killfile charade? You aren't fooling anyone when you reply to half my posts via piggybacks and swim through Google juice to read even more of them. Maybe he is a true tough guy. Stranger things have happened. It's a amazing what a little info you can get on a poster's history on Google, Dave. My favorite about this info on Frank, it the imaginary McDonald's, and the fishing trip he had at the lake in a storm !!!! It's amazing how quickly some people resort to digging up the past when they can't deal with the present. Heck, even Dave agrees with me on this one -- every time I bring up Bush's DUI or business failures, Dave says they are irrelevant. So Vinnie, are you calling Dave a liar? ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
"Frank Gilliland" wrote in message ... On Sun, 10 Apr 2005 19:58:28 GMT, "Pete KE9OA" wrote in : Hey Vinnie............I can help you. The formula for a 1/4 wavelength radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. It should be noted that these formulas are only appoximations. Actual sizes are dependent upon the conductivity and diameter of the elements, and the quantity and angle of the radials. When building a resonant antenna it's a good idea to make the elements a little long and trim to resonance. Very true..........I use a spectrum analyzer with a directional coupler and trim for maximum return loww. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. These are impedances for antennas in free space, and are practical only if you can mount your antenna well above the ground and away from any tall objects. Also true, but a good starting point. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. Close. For lowest loss, the optimum characteristic impedance of coax is 76.9 ohms. 70-73 ohm coax is used as a compromise between low loss coax and coax optimized for minimization of flashover, the latter having an impedance of about 60 ohms. Good memory. And while many people have many different ideas as to why 50 ohm coax is made, it is just a compromise between low-loss/low-flashover coax of 72 ohms and coax optimized for handling power (about 30 ohms, which is too lossy for practical transmission lines). On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. .....uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. I hope this helps. Pete ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
Sounds good, Vinnie....................feel free to e-mail me directly if
you have any questions. Pete "Vinnie S." wrote in message ... On Sun, 10 Apr 2005 19:58:28 GMT, "Pete KE9OA" wrote: Hey Vinnie............I can help you. The formula for a 1/4 wavelength radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. So far, that is what I have read. What I am going to do is this. I am going to add the 45 angled GP, simply because it is fairly cheap, and because it will be much easier to put it up now, than later. The formula you gave indicates that radials should be about 8.8 feet at 27 MHz. If these radials fair poorly, I will take Lancer's advice and build my own. For some reason, the radials are 6 feet. I don't know if they ran 9 feet of wire in there, or what. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. I won't do this. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. I hope this helps. Pete It's does help, Thanks ! I am borrowing an Autek RF analyzer to check the antenna while I am up in the tree. Most people that have purchase this antenna, say that it is tuned very well to 27.205. I should be flat up and down in CB and 10 meters for about 1 MHZ. I will follow up. Vinnie S. |
Oops.............that should have been maximum return loss. Touch
typing...........you know! Pete "Pete KE9OA" wrote in message ... "Frank Gilliland" wrote in message ... On Sun, 10 Apr 2005 19:58:28 GMT, "Pete KE9OA" wrote in : Hey Vinnie............I can help you. The formula for a 1/4 wavelength radiator is (234 / F) whereby F is the frequency in MHz. This will give you the length in feet. For the radials, (237 / F) will give you that length. Always remember...multiply the radiator length by 1.05 and that is another way of calculating the 1/4 wavelength radials. It should be noted that these formulas are only appoximations. Actual sizes are dependent upon the conductivity and diameter of the elements, and the quantity and angle of the radials. When building a resonant antenna it's a good idea to make the elements a little long and trim to resonance. Very true..........I use a spectrum analyzer with a directional coupler and trim for maximum return loww. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. These are impedances for antennas in free space, and are practical only if you can mount your antenna well above the ground and away from any tall objects. Also true, but a good starting point. There was an article in RF Design magazine a few years back, explaining why certain impedances are used in the RF industry. 72 ohms was the impedance that produced minimum cable losses...........50 ohms is a happy medium. Close. For lowest loss, the optimum characteristic impedance of coax is 76.9 ohms. 70-73 ohm coax is used as a compromise between low loss coax and coax optimized for minimization of flashover, the latter having an impedance of about 60 ohms. Good memory. And while many people have many different ideas as to why 50 ohm coax is made, it is just a compromise between low-loss/low-flashover coax of 72 ohms and coax optimized for handling power (about 30 ohms, which is too lossy for practical transmission lines). On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. .....uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. I hope this helps. Pete ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On Mon, 11 Apr 2005 08:03:21 GMT, "Pete KE9OA"
wrote in : snip On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. .....uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. I understood that much. My point was that whenever an antenna/coax mismatch occurs, tuning the output tank (as with a tube final) doesn't cure the mismatch or the resulting signal loss. All it does is protect the final from the reflected power. The output tank should be matched to the characteristic impedance of the coax whether the final is a tube or a transistor. If the coax shows standing waves, the mismatch should be fixed at the point of mismatch, not at the radio. I realize that this is not always practical, but people should know that such a conjugate match just dissipates that reflected power somewhere else, usually from the outside of the coax or the radio. As for ALC, I thought you were referring to a different type of limiting. My bad. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
Imax is a piece of garbage. Get a dipole.
|
Point taken..........it sounds like you are either also in the business, or
have quite a bit of interest. I understand that an output matching network only tunes out the imaginary terms, and that matching the impedance at the antenna feedpoint is the best approach. "Frank Gilliland" wrote in message ... On Mon, 11 Apr 2005 08:03:21 GMT, "Pete KE9OA" wrote in : snip On a final note...........at 37 ohms, you will have a VSWR of 1.3 to 1.................at 75 ohms, you will have a VSWR of 1.5 to 1. What is the difference here? For a transmitter with a tube output and an internal matching network, you wouldn't really see much effect. For a typical solid state transmitter, there would be some difference between the two antenna impedances, because the broadband solid state transmitter would be called upon to deliver more current to the antenna. It probably wouldn't have any effect, unless the ALC circuit was aggressive in its operation. In this case, power foldback would occur into the 37 ohm load. Would it happen? Probably not. .....uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. I understood that much. My point was that whenever an antenna/coax mismatch occurs, tuning the output tank (as with a tube final) doesn't cure the mismatch or the resulting signal loss. All it does is protect the final from the reflected power. The output tank should be matched to the characteristic impedance of the coax whether the final is a tube or a transistor. If the coax shows standing waves, the mismatch should be fixed at the point of mismatch, not at the radio. I realize that this is not always practical, but people should know that such a conjugate match just dissipates that reflected power somewhere else, usually from the outside of the coax or the radio. As for ALC, I thought you were referring to a different type of limiting. My bad. That's ok............sometimes, I tend to think in Greek! Pete Gianakopoulos |
On Fri, 08 Apr 2005 19:31:47 GMT, Lancer wrote:
Dave; I know this was directed to Frank, hope you don't mind if I comment? This is a public forum, comments from participants is what it's all about. A dipole is a dipole. It has 0 db of gain, and that assumes a resonant dipole . If the dipole is non-resonant and requires a tuner to force an impedance match, it will have further losses. It won't stand a chance against a commercially produced (or home made if you are so-inclined) 5/8th wave vertical (with proper radials, not an Imax). Because a dipole/antenna is non-resonant it doesn't automatically mean it will be a more "lossy" antenna. A non-resonant dipole fed with ladder line can/will end up being a more efficient antenna than a resonant dipole fed with coax and a balun. In what way? If the length of the dipole is at a no resonant length, you have to "force" it to a proper impedance match through the use of a tuner. Standing waves will still be present after the tuner, and efficiency will suffer as a result. Why have a resonant antenna at all if a non-resonant antenna works better? It doesn't make sense. I've tried loading up different antennas that I've had to run on bands they were not designed for, and while I could certainly get better than a 1.5:1 SWR, they might as well be a load of bed springs for as well as it worked. I have built non-resonant antennas that beat a 5/8ths. A 5/8ths is hard pressed achieve the claims for gain that it has.The only commercial 5/8th that I seen that was properly decoupled was an Isotron. An Isopole maybe? IIRC, that's a 2 meter antenna. I never particularly liked them. I've had better performance from a Hustler G7. Especially on VHF, you don't see people running non-resonant dipoles. Gain is particularly important there. Proper decoupling can be achieved through the proper use of a radial counterpoise, which is what is lacking in the "stick" style antennas we're discussing on CB I've done this type of antenna myself and never had any problems with local contacts -- in fact, it worked a lot better than the 9' whip on the truck. I find that very hard to believe, assuming identical height and conditions, as my own experiences prove otherwise. I ran a home brewed wire dipole on CB years ago, and used it in addition to my main 5/8th wave antenna. While the dipole worked well when the skip was running, locally, the signal from the dipole was a few "S" units less than the ground plane. With 4 watts of power, you don't get much range on a horizontal wire dipole strung in a tree. Well there's your problem, Dave -- I didn't say anything about horizontal. On the contrary, it's better if it isn't. Yea, if you're talking local. For DX, horizontal is usually better for a number of reasons, most notably a lower noise floor and better take off angle. Horizontal antennas are dependant on height above ground and the conductivity of the ground they are above. The closer to the ground and more lossy the ground, the higher the take off angle. That is correct. For best performance, a dipole needs to be at least 1/2 wave above the ground. Since most man made noise tends to be vertically polarized, a horizontal antenna tends to quieter. Also correct. Like I said before, just throw some wire up into the trees (or whatever tall object happens to be available). Didn't you read the link I posted? Of course. But a dipole is a basic antenna. It has no gain. A properly made purpose built CB antenna will out perform it. Let's look at this from a practical standpoint. If a non-resonant, tuner fed dipole worked so well, then why aren't all CB'ers using one? Why would people want huge 5/8th wave antennas then? Better tell Jay to forget about selling his Interceptor, since a simple non-resonant dipole will work just as well and for far less money. A non-resonant dipole has ONE big advantage. It's a compromise antenna that will work on all the HF bands. That's great if you don't have the room to put up single band antennas for each band. But like any compromise, it will not work as well as a dedicated antenna for each band. Such a compromise is usually acceptable for a ham who has 1500 watts on tap. But for a 4 watt CB'er, who needs to squeeze every watt of ERP he can for best local range, he needs a high gain efficient antenna. Again, non-resonant deosn't mean that its not efficient. Your looking at a non-resonant antenna as a chunk of wire thats just tossed in a tree. A resonant antenna doesn't have any magical gain over a non-resonant antenna just because its resonant. An antenna radiates most efficiently at its resonant frequency. Practical experience with local communications pretty much supports my observations (or more accurately is the basis for them). I've made many dipoles over the years, and none of them have ever matched or even came close to the 5/8th wave ground plane for local work on CB. DX is another matter. Dipoles work very well there. Perhaps that's why many H.F. hams have several different antennas to switch to, to take advantage of varying DX conditions or groundwave, as their communications dictate. When working 40 meter groundwave, a ground mounted vertical is often a superior choice. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Sun, 10 Apr 2005 20:35:06 -0700, Frank Gilliland
wrote: On Fri, 08 Apr 2005 17:02:43 -0400, Vinnie S. wrote in : On Fri, 08 Apr 2005 13:30:51 -0400, Dave Hall wrote: Believe me. I have nothing to worry about. Vinnie S. You don't believe his callsign is WA3MOJ do you? I don't know what to believe from him. But if some lardass steps foot on my property, I will look thru his wallet for ID will I hold his face in the dirt. And if he doesn't have a wallet, then I will get the info from the car. .....oh brother, he's a crybaby -and- a tough-guy. This is just too good to be true! And it don't look like I am the only one !!! I did a little search on you in the archives. This is precious. http://groups-beta.google.com/group/... 2f3b40d85682 Don't you think it's time you quit with the killfile charade? You aren't fooling anyone when you reply to half my posts via piggybacks and swim through Google juice to read even more of them. Maybe he is a true tough guy. Stranger things have happened. It's a amazing what a little info you can get on a poster's history on Google, Dave. My favorite about this info on Frank, it the imaginary McDonald's, and the fishing trip he had at the lake in a storm !!!! It's amazing how quickly some people resort to digging up the past when they can't deal with the present. But the past is what sets a pattern of behavior. Look at what they're digging up from Mikey Jackson's past. Looks like Vinnie has exposed some hypocrisy from you. So maybe you should be a little less zealous to call other people hypocrites in the future. Heck, even Dave agrees with me on this one -- every time I bring up Bush's DUI or business failures, Dave says they are irrelevant. So Vinnie, are you calling Dave a liar? You should leave the spin and deflection tactics to Twisty. He's had way more experience. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Fri, 08 Apr 2005 18:27:15 -0700, Frank Gilliland
wrote: On Fri, 08 Apr 2005 13:59:47 -0400, Dave Hall wrote in : snip Maybe you had difficulty, but there are a very large number of hams -and- CBers who don't share your ineptitude. A dipole is a dipole. It has 0 db of gain, Wrong. A 1/2-wave Hertzian dipole has a gain of roughly +3 dBi in free space. Isotropic is a theoretical spherical reference model which does not exist in reality. A dipole is THE reference antenna, by which most credible gain claims are based against. It has 0 dB when referenced to itself. Isn't that what I just said? and that assumes a resonant dipole . That's an assumtion -you- made, and it's also wrong: A resonant dipole can be any multiple of 1/2-wave, and has a gain that differs depending upon the length and directionality. Then it's no longer a half wave dipole. You are now talking double ended zepp designs, which do exhibit gain over a 1/2 wave dipole If the dipole is non-resonant and requires a tuner to force an impedance match, it will have further losses. Wrong again. A tuner only adds insertion loss, which is usually quite small if it's built with quality components. The insertion loss is easily overcome by slightly increasing the length of the elements, which is no big deal since the antenna is already non-resonant. You fail to consider the standing waves which will still be present in the feedline due to the mismatch. A tuner only presents a proper match to the transmitter. With a high mismatch in the feedline, losses increase as well and creating a tendency to radiate from the feedline. In order to compensate for this the tuner should be mounted at the feedpoint of the 4:1 balun that is normally used to feed 450 Ohm ladder line to such designs. But such is impractical for guys who change bands and frequency often, unless the tuner is automatic. But keeping with the original perspective, of a simple antenna system for Vinnie, this falls far short of that objective. It won't stand a chance against a commercially produced (or home made if you are so-inclined) 5/8th wave vertical (with proper radials, not an Imax). Well guess what, Dave -- a 5/8-wave antenna is a non-resonant antenna and requires some method of impedance matching. Thank you. A 5/8 wave is most certainly resonant. It's just that the feedpoint impedance is high and needs to be transformed. It's a different issue than forcing a match from something that is not resonant naturally. You can have a 1:1 SWR but not be 50 Ohms. Time to read some more books. Or better yet, befriend an experienced ham to show you. I've done this type of antenna myself and never had any problems with local contacts -- in fact, it worked a lot better than the 9' whip on the truck. I find that very hard to believe, assuming identical height and conditions, as my own experiences prove otherwise. Oh, the humanity..... This coming from someone who looks at people who share healthy relationships as being "co-dependant", and prefers instead the isolation of "independence". I ran a home brewed wire dipole on CB years ago, and used it in addition to my main 5/8th wave antenna. While the dipole worked well when the skip was running, locally, the signal from the dipole was a few "S" units less than the ground plane. With 4 watts of power, you don't get much range on a horizontal wire dipole strung in a tree. Well there's your problem, Dave -- I didn't say anything about horizontal. On the contrary, it's better if it isn't. Yea, if you're talking local. For DX, horizontal is usually better for a number of reasons, most notably a lower noise floor and better take off angle. A horizontal dipole can have a wide variation in take-off angle depending on height above ground, ground resistance, proximity to other structures or objects, etc. Yea, so? And the noise floor may be slightly lower but that's a product of it's directivity, as compared to a vertical which is omnidirectional. No, it's a product of the fact that most atmospheric and man-made noise tends to be vertically polarized. A pair of phased verticals, as well as any other directional antenna or antenna array, will also have the effect of lowering the noise floor. Not if the noise isn't concentrated in a single direction. Like I said before, just throw some wire up into the trees (or whatever tall object happens to be available). Didn't you read the link I posted? Of course. But a dipole is a basic antenna. It has no gain. Wrong again. As I said before, a 1/2-wave Hertzian dipole in free space has about 3 dB gain over an isotropic antenna; but a dipole is merely an antenna with two elements and is not limited to a 1/2-wave Hertzian configuration. Not only that, but a tuner isn't limited to dipole antennas -- they can load up a long-wire just as easily. Ah, so you're changing the parameters of the discussion. Long wires are inefficient on CB as well. Been there, done that. A properly made purpose built CB antenna will out perform it. Get a clue, Dave. You're an Extra, right? What's the name of that tech school you claim to have attended? What's your call sign Frank? Frank, all the king's horses and all the books you read will not make up for your glaring lack of experience. Get out from behind the table and DO something, and then report back. Let's look at this from a practical standpoint. If a non-resonant, tuner fed dipole worked so well, then why aren't all CB'ers using one? Why would people want huge 5/8th wave antennas then? Better tell Jay to forget about selling his Interceptor, since a simple non-resonant dipole will work just as well and for far less money. This resounds back to your argument that roger-beeps were illegal because most radios didn't include them. The problem is that a tuner requires a little skill and practice to use, which is beyond the scope of the intended purpose of the service (a plug-n-play radio service). Antenna tuners were available as an accessory for CB for less than the cost of a good SWR meter. Granted they were simple coaxial in and out tuners. A tuner requires readjustment when changing channels within the CB, and most CBers don't want to deal with the hassle. So you are now claiming that CB'ers are too "dumb" to handle that? And to add further evidence to your lack of experience with CB, it was common that "matchboxes" were often used by CB'ers to "correct" a mismatch within their antennas. Instead of taking the time to properly tune the antenna, they forced the match with the tuner. The radio was happy, as it saw a 1:1 SWR, but the signal was not so good. When a more knowledgable person would finally retune the antenna, and the tuner was removed, signal improved considerably. Regardless, there are still many CBers that do indeed use a tuner, not just with prefab antennas but also with homebrew and beverage-can hooks. None of which are work a tinker's dam for local CB communications. And just about every CBer who runs a tube linear uses a tuner because it's built into the amp, which by itself blows big holes in your "practical" argument. Not at all. A tube amplifier requires a tuner because the impedance of a tube is much higher than 50 ohms, and needs to be transformed. It's not practicality, it's necessity. Then there is the issue of the non-resonant 5/8-wave antenna..... oh, Dave, when will you learn? The question is Frank, when will you start? A non-resonant dipole has ONE big advantage. It's a compromise antenna that will work on all the HF bands. That's great if you don't have the room to put up single band antennas for each band. But like any compromise, it will not work as well as a dedicated antenna for each band. Such a compromise is usually acceptable for a ham who has 1500 watts on tap. But for a 4 watt CB'er, who needs to squeeze every watt of ERP he can for best local range, he needs a high gain efficient antenna. If that were the case then every CBer would have a 5-el yagi on a 30' mast and a 9' whip on their vehicles. Most high performance CB'ers do. For ham band use, I agree with you, just not for CB. What's the name of that tech school, Dave? What's your call sign Frank? I'm not a ham. Yet you are trying to impart your opinion on a subject you have not participated in? I answered your question, now you answer mine: what's the name of your tech school, Dave? The fact that you keep asking, makes me all the less likely to tell you. Frank, your experience with both ham and CB radio is sorely lacking. You read a few books and web sites and think you have all the answers. OTOH, I've walked the walk for the last 30+ years and have played with more antennas and equipment than I can remember. I have also been in contact with people in the know when it comes to antennas. What I know, I know through experience, and that's worth 10X what you read in any book. Which explains why your theory is severely lacking. If you took the time to actually learn why these things work and -then- applied them to your experiences, you could be the guru you think you already are. But you don't and you're not. Instead you do things backwards: you theorize about radio based on your own experience, then read only enough to validate your own conclusions whether they are right or not. If the evidence supports the theory, then it's valid. If not, then the theory is wrong. You are a perfect example of someone who is book-smart and street foolish. You will sit there and tell people, who do these things every day, exactly why they can't possibly work. While we sit here and laugh at you, because we've been there and done that. Check this out, Dave: Education doesn't come from a textbook that some geek sat down and wrote just for ****s and giggles. It's a compendium of knowledge that has been collected from over a century of research, experimentation and practical experience by experts in all aspects of the field. Those experts didn't become experts simply by playing with CB radios as a hobby for 30 years. And an education doesn't include a couple textbooks, a few lectures and a test -- it also includes years of experience with the practical application of that knowledge. No kidding. You seemed to have failed the "practical application" aspect. Hell, you never even heard of the term "drying out" in reference to electrolytic capacitor aging, and you try to cover this glaring hole by claiming a pompous, superior attitude as if this was beneath you. When you mock those that have a formal education and extensive experience in electronic communication then you mock the same people who made the television set you watch way too much, the telephone and cell-phone infrastructure that keeps this world talking, the NASA and JPL engineers who communicate with space probes billions of miles away, etc, etc, etc. I'm not mocking them. They know what they are doing. And I work with many of them on a daily basis. You probably have products in your home (or will) that I have had a part to play in their development. I work in the field every day. I am not mocking them, I am mocking you. You who CLAIM to be educated, but evidence suggests you are sorely lacking in practical application of whatever it is you might have learned. While I may not have participated in any world-changing technology, I certainly have an education and the experience in the field that puts you to shame. While you tend bar and drive a 20+ year old truck...... Yet -you- try to teach -me- theory based on your education from a third-rate vocational tech school, a few years in a CB shop, and your experience in =amateur= radio. As far as you know. But it is evidently light years ahead of those internet websites you lift your information from while you sit at home alone with no other people to "relate" to. And here's the kicker: Do you have any idea where I came up with the idea to just throw a couple wires in the air and load them up with a tuner? A ham. Not all hams are mensa candidates. And most hams know that one antenna solution, which may be great in one application, is not necessarily good in another. In ham radio, there is no "one size fits all" answer. But then again, you wouldn't know that. You're not a ham (or CB'er). Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Fri, 08 Apr 2005 18:27:26 -0700, Frank Gilliland
wrote: On Fri, 08 Apr 2005 13:28:53 -0400, Dave Hall wrote in : On Thu, 07 Apr 2005 16:44:59 -0700, Frank Gilliland wrote: On 07 Apr 2005 23:32:45 GMT, Steveo wrote in : snip I suppose they drive like that everyplace..it's a matter of being in the wrong place at the wrong time, or your truck is a magnet. I have one of those too. I think -I'm- the magnet. The Dart I drove in college was hit 5 times, the LTD got hit twice before it was totalled, the S-15 was rear-ended by an ambulance, the LeBaron was hit three times in two weeks, etc. I've had the S-10 for two years and it's been hit twice -- both times while it was parked! All in Spokane. Fortunately, I've only been hit once when I had a passenger, and that was the ambulance wreck so at least there was help available if someone got hurt. There's something cosmic about that. I've had 2 major accidents in my whole life, and both were in the same car. Neither were my fault. Nothing is ever your fault, Dave. We discussed this problem in your last therapy session. What therapy session? The one where you exposed yet another shortcoming in your insight? I find it interesting that someone who shuns regular human contact would attempt to pass themselves off as someone with some experience at it. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Mon, 11 Apr 2005 13:46:07 -0700, Frank Gilliland
wrote: Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. I understood that much. My point was that whenever an antenna/coax mismatch occurs, tuning the output tank (as with a tube final) doesn't cure the mismatch or the resulting signal loss. All it does is protect the final from the reflected power. The output tank should be matched to the characteristic impedance of the coax whether the final is a tube or a transistor. If the coax shows standing waves, the mismatch should be fixed at the point of mismatch, not at the radio. So much for running a non-resonant length antenna through a tuner. Sounds like you read a different book this time. I realize that this is not always practical, but people should know that such a conjugate match just dissipates that reflected power somewhere else, usually from the outside of the coax or the radio. Which is the main reason why a non-resonant, tuner matched antenna is less efficient than one that is resonant. But you'll argue that with me just to argue. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
On Mon, 11 Apr 2005 08:03:21 GMT, "Pete KE9OA"
wrote: It should be noted that these formulas are only appoximations. Actual sizes are dependent upon the conductivity and diameter of the elements, and the quantity and angle of the radials. When building a resonant antenna it's a good idea to make the elements a little long and trim to resonance. Very true..........I use a spectrum analyzer with a directional coupler and trim for maximum return loww. So do I. It gives a much better picture than a simple SWR bridge. The feedpoint impedance of a 1/4 wave ground plane is 37 ohms when you have the radials at a 90 degree angle with respect to the radiator. If you have the radials drooped at a 45 degree angle, the impedance rises to approximately 50 ohms. If you have a single radial drooped at a 180 degree angle with respect to the radiator, the impedance rises to 75 ohms. These are impedances for antennas in free space, and are practical only if you can mount your antenna well above the ground and away from any tall objects. Also true, but a good starting point. Some people like to make the subtle conditions into much greater points than they need to be. .....uh, what? Both tubes and transistors use matching networks, so I don't know what distinction you are trying to make there. Power will be reflected from an antenna/coax mismatch -regardless- of whether you have a tube or transistor final. And what does an ALC circuit have to do with transmission line propogation? This pertains to solid state amateur transceivers that don't have an adjustable output matching network.........most of today's units have fixed-tuned bandpass filters after the output stage. I am not referring to transmission line propagation; I am referring to the fact that, with a fixed-tuned output network that expects to see a 50 ohm characteristic impedance, the ALC can fold back the power. Usually, that doesn't occur until a VSWR of 2 to 1 is reached. My explanation is for illustrative purposes only. Not only that, but the bandpass filter characteristics of the output stages can change if the load impedance changes significantly, increasing loss and broadening the cutoff points. Dave "Sandbagger" http://home.ptd.net/~n3cvj |
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