Breaker 19 - Help with my CB Setup

I have a J&M CB system on my BMW which works at best sporadically. You'd think that someone who spends their life dealing with multichannel wireless microphone systems might be good at troubleshooting but apparently when it comes to CBs I suck! Well it is AM y'know...

So I'm looking for a CB radio tech in the Dallas that understands cable length balancing and all that goodness and can get me set up talking & listening.

So, c'mon back there good buddy and hook me up here!

As they say on Craigslist, this is a paid gig.

You are way past me, all I did was move the antannae up or down while watching a SWR meter. Don't know where the meter is now. What "cable" length are you talking about?

If he is still around, the guy on Waddill st in McKinney has always done me right.

1816 N Waddill st McKinney

75 N, exit 380 and go E. Waddill is only a few blocks from the hwy, hang a right onto Waddill and his place is the white house on the left with the big antenna array on the side.

I know where a cb shop is in Fort Worth that has been in business a very long time.

focus frenzy said:

I know where a cb shop is in Fort Worth that has been in business a very long time.

Click to expand...

Pray tell...

Sid's CB 6204 south freeway, Fort Worth, 817-293-1333

coming south on I-35w take Altamesa exit and follow access road south, it will be on right just after club ice.

go past there everyday on way to customers location.

Cable or coax length is usually half of the wavelength . 11 meters or cb is 36 feet so half is 18 ft of coax.


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With J m cb I have had decent results with a no ground plane antenna and grounding the radio with a jumper to a good ground point.


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I have given up on CB, and even more so on CB on the bike. There is almost no chance to get a good standing wave to to the fact that you have no decent ground available. And mind you, ground available does not mean connect it to the frame somewhere, in RF that is not ground.

Basically when you look at a car and the antenna mounted in the center of one of the metal sheets. That is what RF needs as ground. You can mount it on the corner , knowing that your RF pattern will be off. A frame rail just is not enough.

The only band I have and had decent experience with on the bike, and was able to get decent antenna mounting and grounding is the 440Mz ham band or the 462.467MHz FRS/GMRS band, even the 2m based MURS or ham radio had problems.

And the kicker is that if you are unable to get a good standing wave in your antenna your transmit power will be reduced **DRASTICALLY**

coils built onto antenna does effect wave length.

s w r meter?
try different length feed line to your ant.( if your having high s w r 1.5 or worse. 1.1 is ideal

or measure ant and cut to length for just a couple of frequencies your going to be using if all else fails.
let us know cause some of us have kinda been around communications for quite awhile .

Technically there are a few options you have. The simplest end fed antenna (antennas we deal with mostly in a mobile environment, basically antennas which are fed on one end) is a 1/4 wave antenna. For CB a 1/4 wave is approx 11m/4*0.66 (The 0.66) is what is a speed factor, since waves in on antenna do NOT move with the speed of light) = 1.85m or 6ft. Thats quite long. Yes, I know you can shorten antennas with coils, but you can have either a ****** ground, then the antenna needs to be up to snuff of you cane have a bad antenna (shortened) then you ground needs to be perfect (fat chance you are going to be able to pull that off in a bike)

The VSWR only determines how good the whole antenna system is adapted to the transmitter. It does NOT say anything how good your antenna resonates and how easy the waves come off of your antenna. Point being that a dummy load, being just a 50Ohm resistor has a VSWR of 1.0, so resonates quite well, as far as the SWR meter is concerned but does not transmit anything.

Coming back to antenna design --- CB is the wrong band for a bike. You will never be able to get good results due to physical limitations.