antenna help
Discussion in 'CB Radio Forum' started by stroker22, Feb 2, 2013.
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Why would you want to make the magnet less conductive to the metal body of the truck? Sometimes I think the term dielectric is misunderstood. http://dictionary.reference.com/browse/dielectric?s=t
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guy at the cb shop ordered my a k40 antenna and texas star amp
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What size amp and whar model K40?
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volt either its the texas star dx250 or the 100w watt one im not sure which k40 the guy at the cb shop ordered the stuff for me.
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102 stainless steel whip is the best you can get mount it to your bumper if you dont want to do that then get a magnet mount for top of cab and put a monkeymade on it wilsons are good too
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Generally, the longer the antenna, the better its performance. "Generally" here means equal style of construction, same coax, style of mount, etc.
A helix is the exception to the rule about coils not radiating. In order to qualify as a helix antenna, there has to be a certain relationship between the diameter of the "coil" part and its length. They're commonly seen on "rubber ducky" antennas on VHF and UHF handhelds. They're not as efficient as full length quarter wave antennas, but most people don't want to contend with an 18-inch rattail antenna on a handie-turkey hanging on a belt, either. I still remember the late '70s, when the Santa Ana (CA) Police were using the 460 MHz band with their HT-220 handhelds. Presumably a 6-inch rattail antenna was too cumbersome (?!?) so they used UHF rubber duckies (the shorter ones, around 1 inch long). At around 12 dB loss, they almost qualified as RF chokes, but SAPD had several repeaters around town, and the range handicap was made up for by never having to talk very far -- and they were using the 4-watt power hog version of the radio, too. We poor schnooks on the FD had to contend with low band, and the only portables we had were the older HT-200s with a base loading coil, plugged into the External RF jack, and with a ring terminal around the base of the telescoping whip. We were trying to get a 30-inch whip to work on 33 MHz, nearly akin to a base loaded whip for CB, but with hardly any ground plane, save the huge die cast metal back covers on the radio.
Sometimes there's just no substitute for RF power, as long as *everyone* has it and understands the limitations of antenna system design. And, of course, with no repeaters available on CB, it's "every radio for itself".
A helix distributes the shortening of the physical size over a longer portion of the whip, rather than having a nearly-plain whip radiator and a "lumped" coil, where the coil is all sitting at one place along the length. Depending upon where the coil is on the whip on your Wilson, you may already be ahead of the game, but there's more to antenna performance than just coil design or placement.
The longer the antenna that you can fit, as high up as you can get it, is most likely to work consistently the best for you. At some point, the comparisons between Wilson, Firestik, Bar-Jan, Francis, and all the other manufacturers become a matter of personal preference. Past luck with a limited variety of antennas, anecdotal evidence from other users with failed equipment, or having been lucky with an antenna that's lasted over a year can lead to much digging-in of heels in an attempt to out-shout good science.
Recalling that a dummy load is an ideal match but a really poor radiator, and a 102-inch over a metallic surface that's 20 feet across would be a nearly ideal antenna system (though not very practical to drive around), just figure that there will be a lot of shades of gray in whatever you can run. At typical mobile power levels (even those that exceed the lawful limit), nearly *any* system that's correctly installed will work.
Since you're just now getting into CB, the ability to run 1,500 watts is probably neither likely to happen soon or be especially useful (when you consider that the receiver won't hear better just because you may be transmitting several hundred), I'd suggest comparing what kind of performance you're getting with others with similar installations.
FWIW, I run a stock Cobra 25 to a variety of antennas that I change out depending upon how long I'll be on the road and whether or not I'll need to garage the buggy when I get home. While it may fly in the face of "conventional wisdom" (and I use the term very loosely here), I can get five or six miles to other mobiles with my 24-inch truck stop (Diesel/Bar-Jan) Fibreglas whip. But I'm usually talking with people with better antennas, which helps both their transmit *and* receive range; so even if my signal isn't a powerhouse, the others' stations may be better, which helps them make better use of my lower transmitted field strength.
Remember that to communicate you have to have at least two stations involved. If your station were vastly inferior, the number (or distance away) of *the other end* of your transmission circuit would be lessened. I believe if you stick to the basics like the antenna goals above, and if your radio is putting out nominally the right power, cleanly modulated, and your receiver isn't grossly misaligned by a "technician" who didn't use the right service gear to tune it, you'll have decent performance.
Since you are admittedly new to CB, I'd suggest a modest investment at a reputable shop to check over your system and see if everything has been installed correctly and that the radio is doing what it's supposed to on transmit and receive. I'd resist buying anything that has the word "miracle" on the label (or in the technician's description) and that just happens to be hanging on his/her/its wall.
While it's possible to measure performance differences with decent test gear, that last tenth-of-a-watt of output power won't make a difference in how far you talk -- unless your output power *was* zero, and now puts out 0.1 watts.
Every time I note someone who has had their radio "peaked, tuned, and modified" I wonder just what was done. If it was done with nothing more than a wattmeter and a diddle stick, it's likely that you're putting out trash all over the band (and possibly other bands).
The other term I often see is "tweak". Aside from an alignment, I don't know whether all those terms like "peaked and tuned" are just lumped together, like "kit and kaboodle" (anyone ever seen just a "kaboodle?).
I get that your radio has been made to work on the CB frequencies. If that Lee hasn't been aligned to favor the 11 Meter band after the conversion, you've likely already handicapped the potential range and clarity of your radio, and any antenna fiddling around that you can do, while helpful, still won't make your system work to full potential.
Sorry for such a wordy response, but I've been licensed to transmit on short wave bands (in which CB falls) for over 50 years, and I've made a living at it for nearly 40. There's a lotta old cobwebby stuff rattling around up there.
73Last edited: Feb 17, 2013
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