Any of you guys deal with noise coming from the fuel pump? Ken, especially you since we have the same truck? I have a Cobra 29 and when I tried tuning it the SWR was through the roof. Lots of engine noise through the radio too. I have a 4 foot K40 mounted to the front end of the bed, radio powered from the battery and about a foot extra of coax laying under the back seat. Does this need a better ground possibly?

 

So is there anybody in the area that could maybe help me out? I have never done this and I would like to get it done correctly so I can stop dumping money on this.

 

From everything I've read, the position of the antennae may be your problem. Any parallel metal within, I believe, 20 inches of the antennae will reflect transmissions back at the antennae causing a higher SWR. The best place to put the antennae is directly in the middle of the roof or at the rear most place of the bed along the bed rail. This way there's no surrounding metal to reflect the radiations back at the antennae.

I have mine on the front fender attached by one of the fender screws under the hood. There's a good 15-20" between the antennae and the windshield/a-pillar and it's not exactly parallel, so it doesn't reflect directly back at the antennae.

At least that's my understanding. I'm pretty new to CB radios. I have the Larsen NMO27C for base and antennae (4'4.5") and a 50ohm 18' coax cable.

 

thanks mtylerb

 

So does that mean that everyone running the dual antenna's on the bed next to the cab is doing it wrong?

 

I didn't say anything about doing it wrong. It's just inefficient compared to other mounting points and may be contributing to a higher SWR. As posted previously, a high SWR will eventually burn out your radio. The other issue is with the dual antennas. They need to be at least 9' apart and our trucks aren't wide enough to accomplish that.

 

I did not know that! Do you know of a good website about CBs?

 

How does a CB radio antenna work?
How does a CB radio antenna work and why does it need to be tuned?
How to Choose the Right CB Radio Antenna
Wikipedia: Citizens' band radio

There's a few. I read for 3 days and contacted a local CB radio shop before deciding on an antennae and best location to mount it. There's tonnes of information out there.

 

I havent used mine in my current truck but I did have it set up in one of my old trucks. I bought a cigarette lighter plug at Walmart and connected it to the cb unit's wiring.

Its a cheap old unit that I got from a car a friend was junking but it works ok and has decent distance reception. Its got a cheap magnetic mount antenna from Walmart that I bought to replace the corroded one it came with.

 

Great. Thanks a lot

 

Do some studying on radio waves, dual antennas are a joke and are not worth the cost. Mobile antennas work better if they have a flat (as in the horizon) sheet of metal to bounce/gain the signal off of. Test it out, get to a point you can barely read someones signal and aim your car in their direction and then 90 degrees left or right. then if you have a mag mount, move your antenna around on the truck/car. you will be amazed by the change in output and input. This is why most mirror or bed mounted antennas run into issues when a the truck is facing a certain direction in relation to the other party. Also, keep in mind, the whole length of an antenna is used to create the frequency wavelength... if you have a big metal object (the cab) blocking half your signal... how far do you think it will transmit?

reply to a previous post. I run great filters on my Kenwood, I do not have an issue with noise.