Electronics Life

CB Radio

I got all inspired when I went camping with my brother-in-law in September. His friend from Fort Collins has a fully tricked out off-road vehicle complete with a CB radio. Well, I got excited about that because, since the late 90’s we’ve had my grandfather’s old Ford van, and he was big on CB, having a camper and secretly being a tech nerd before it was cool. I still have his mobile CB radio, which we tried out at the end of this camping trip.

Except I can’t seem to get it to work. It turns on, it hisses, and the squelch feature seems to work to some extent, but I get absolutely zero variation in the noise, even when moving the little 3-foot whip antenna around, mounting on the truck roof for grounding, and everything else I could think of.

That’s when I decided to “invest” in a Monkey Ward 775 CB radio. I’m assuming this is probably also a mobile model due to the u-bracket on the top. However I’m looking up how to make a home-brew antenna for this, and I’m guessing it’s the 3-foot whip that makes a mobile station mobile. Maybe a base station has more features and such, but I’m new at this anyway!

However, the issues I have at the moment are crippling: The radio came with a power input cable of two wires and two tab connectors, a keyed microphone, and a user manual. That’s it.

So I need to come up with a proper power connection of 12VDC, and somehow create an antenna that will work and be ideal while still not violating the HOA covenants of not having anything over the roofline of the house. Additionally an 8-Ohm speaker or headphone converter may be necessary if the keyed microphone doesn’t also have something built in.

But on to antennas! I found this website from the Thunder Mountain Radio Group. They say that ideally, a base station antenna for CB frequencies needs to be around 102 inches (a quarter wavelength of ~11 meters). And this is not a single whip antenna, but a combination of two antennas in a dipole arrangement, each at 102 inches.

That’s 8.5 feet of wire extending from a center point where 50-ohm coax is connected and runs all the way back to the actual base station radio.

My idea when it comes to this antenna – since I’m not permitted to mount this thing so high up that I’d be able to talk to people in Denver, how about I instead run the antenna wires horizontally beneath the top bar of the vinyl fence that runs along the side of my property? It’s actually kinda perfect – minimal metal to screw up the signal, and sort of out of the way of everything else except for a few aspen trees. It’s not THAT ideal, but it’s at least something better than a 3-foot whip. The only other solution I could think of would be to take the rig all the way to work and mount it on the roof there. I know Steve at Mountain States Electronics has always had a nice setup of his own. Maybe I could talk down the block to him.

Then comes the coax. I am thinking standard 50-foot RG-58 spool, which I can buy with UHF connectors pre-installed for $17 on Amazon. Or I could get a single connector from Digikey, a spool of RG-58 for $20, and make my own.