i got a cb. now what antenna length

[2000wrangler]

i got a cb this weekend, but now i dont know what length antenna to get. i dont want a really long one, but i think i need one to get above the roof line (its a TJ). i need some input on this one.

[Tug-n-pull]

Keep it just lower than the top so when in the woods it will not be flipping of the tree limb all the time! Does not need to be above the body to talk just make sure it is well grounded and solidly mounted. tug

[bchcky]

i cant quite help you with how long you should go, depends on how far away you will be from everyone, and how good the antenna you end up with is in the first place. but i can tell you, if you get a long one, which would be a whip antenna, you could always tie the top end down somewhere, forming an arch. you'll still get the same reception, it just wont be as high and knocking trees and stuff.

and i've looked around, you can get one at radio shack for 20-30 bucks depending on what you want. dont overspend.

[jps4jeep]

I have to dissagree with tug for once, For the best performance out of your CB, you will want the antenna to extend about 6 inches beyond the roof line, any more than that is not necesary. Any less and you will only be able to hear incomings from a short distance. Also, what you get the antenna, DO NOT CUT THE CO-AX It id designed to use all the length!

[graewulf]

Originally Posted by jps4jeep

I have to dissagree with tug for once, For the best performance out of your CB, you will want the antenna to extend about 6 inches beyond the roof line, any more than that is not necesary. Any less and you will only be able to hear incomings from a short distance. Also, what you get the antenna, DO NOT CUT THE CO-AX It id designed to use all the length!

OK, my 2 cents worth... lol

the longer and higher the better if you want range - if you want to only use it on the trail it doesn't matter much. As for cutting the coax, cut it to length once you have it installed if you have more than a foot or 2 excess. the "DO NOT CUT THE CO-AX It id designed to use all the length" thought process is actually a myth. The length really does not matter. What is important is that you tune the antenna with a SWR meter to get a proper match to the radio. Every radio is different, as is every antenna/cable combination. YOu can test 2 18' cables and get a different SWR reading.

some links that support this:
[url]http://www.truckingboards.com/trucking/upload/showpost.php?p=26391&postcount=11[/url/
http://cbworldinformer.net/_disc1/00000039.htm
I found a good writeup a few years ago I think its time to hunt it down again.

the important factors are:

well grounded antenna - don't rely on the coax to do it for you
good quality coax
securely mounted antenna

that's it. Getting the antenna higher will help you transmit distance because the vehicle will block some of the signal.

[Inspector-Gadget]

Hi-Ya 2000wrangler,

Another $00.02 worth: mine. You are going to be rich for everybody's $00.02. :wink:

The CB coax cable length thing is indeed a canard, just as graewulf stated. The CB coax cable length myth dates from the late 1960s, early 1970s when magnetic-mount antennae became available for vehicle CB radio installations. The manufactures of magnetic-mount antennas cautioned against altering the length of the prefabricated coax cable supplied with their mag-mount antennas. For good reason: there is no direct antenna mount electrical ground when using a magnetic-mount antenna, so coax length was an important design consideration. (Why that is true is unimportant here.)

Somehow, over time, the legitimate cautions applicable to the mag-mount (ungrounded) antenna coax cable length were misapplied to the grounded antenna mount more typically found in a vehicle CB radio installation. That myth lives on to this day.

There are no valid electrical-transmission efficiency reasons to cut the CB coax cable or to keep the cable at some finite length. Two caveats: all required coax cable connectors must be properly installed, and the radio-coax-antenna system should be "tuned" (impedance matched) using an SWR meter, signal strength meter or equivalent.

Actually, the antenna impedance is adjusted to match the coax impedance during the tuning process. The coax cable impedance and the CB radio output impedance are design-determined and not adjustable.

Regards,

Gadget