Laws and Fitting of CB Radio??

I'm interested too Vaxxi that you get loads of 'noise', I do on my Jimny although like you the cb is connected directly to the battery. My antenna is mounted through the middle of the bonnet which at the time seemed like a good idea - nice big ground plain. However, of course its directly above the engine electrics. The noise is though, I think, the fuel pump as if you turn the ignition on without the engine running the sound starts and stops, but starts again when you run the engine. My Samurai did exatly the same thing (injection engine) but was better with a mag mount aerial, and strangely better on AM rather than FM.
Any ideas anyone on how to fix it. I did buy, but haven't fitted, a noise suppressor capacitor for the fuel pump but its not easy to get to the fuel pump.

Here's mine, I took the + feed from the interior light and also the - from a mounting screw in the light.
Luckily, it doesn't pick any 'noise' up from anywhere.
Having said that, I haven't tried it with the wiper motor running.



Twig mounted here:



K

Obarno wrote: The noise is though, I think, the fuel pump as if you turn the ignition on without the engine running the sound starts and stops, but starts again when you run the engine.

I haven't looked into fixing the problem yet. My CB has a power meter indicator, and with the engine off the needle only jumps to max 25% of the scale; with the engine on, it sits constantly above 50%, so the squelch control needs to be pushed almost to 75%.

From what I've read the diagnosis goes like this: with engine on, disconnect the antenna; if you still have the noise, then it's from the electric part and not the antenna. If the noise is gone with the antenna disconnected, then it means the antenna picks up interference from the car's electrical system. To make it even better, the power cable can act as an antenna also and bring unwanted noise.

If the problem's electrical, either:

• get a twisted power cable to make it withstand interference better (some people use a radio cable, the one with outer braided shielding and small copper core, it's enough to power a CB) or put a ferrite doughnut on the cable
• only get your + from the battery and ground from somewhere else, preferably a factory ground point (this is what I'll try first, as it seems to be a very common cause for noise)
• shield the power cable
• if it's a high pitched whine proportional to the engine RPM, then it's AC noise; only in this case a filter will help.
• if your cable is parallel to other power cables, reroute it (perpendicular would be best)

If the noise comes from the antenna, then it's trickier. The antenna is suppose to pick up signals, so it's doing its job. However, it means the car is "leaking" RF signal, which can come from the coil packs, spark plugs and their wiring, etc and you have to find a way to shield them (maybe line up the hood with some thin metal sheet, haven't thought yet of how to fix it).

Jason, Im probably going to be heading to it on the Sunday, not sure what time yet! I dont know who else is going, I checked the events page and there was a topic about it but only a couple of people responded to it and that was months ago.

Thanks very much for the replies about the CB, loving all the ideas. By the sounds of it using the cigarette lighter is going to be the way for me to go as I can then have it in and out. With regards to the magnetic aerials I dont want to damage the paintwork unnecessarily...any way of avoiding this?

Also, do you guys have any particular models of CB that you would recommend? Looking to spend around £80.

Andrew

P.S. I love the idea of mounting with the interior light, looks really good!!

You can still wire it to the battery but use a pair of bullet connectors just behind the rig so it can be easily removed, i done this as i often use the lighter socket for charging my phone or sat nav.

If you're on difflock theres a guy who's user id is . thats his user id . i've not missed a word out. He does deals on tti cbs that get good reviews, theres also some really good deals on ebay for midland and tti rigs. Do your homework though as some are cheap but don't come with a mount or twig and some make the difference up with postage,
something like this:
cgi.ebay.co.uk/MIDLAND-98-PLUS-80CH-UK-E...M&hash=item45f863642

I was after one of these but my dad got his finger out and dug out his old one for me, i've used a mag mount for now and used a pair of hose clips to secure it against a roof bar to stop it getting pulled off when off road but will be changing to a truck mount soon as i've got a quick release for the twig. I got one of the big mag mounts from maplins as those little ones wouldn't last 5 minutes off road.

If you're going to be taking it off though you can just put a rag under the magnet to stop it scratching and give the area a quick clean before putting it on so theres nothing under it to scratch the paint.