Cellar

Problem is it is working when I think it shouldn't. I'm re-installing my CB on my current truck. It worked prefectly well in when I had it installed in the other truck. Once, the ground connection came loose and it didn't work. Hooking the ground wire back up fixed the problem.
The CB is a cheap Radio Shack unit I got for next to nothing.

Now what really has me confused, is that hooking up +12v power to the CB with no GND connection causes the CB to seemingly work fine! (I say seemingly because it turns on and static is heard. I'd have to drive to the truck stop to get any reception to test.)

I have the power running in from a new aux fuse box I installed with some equally new Hella lights. Originally, I had the CB +12v connected with the power feed to the light switches. Figuring that the CB might be shorting to ground via the switches, I ran the CB power off it's own fused terminal and encountered the same thing.

There seems to be no other electrical connection to the CB other than +12v power . So how is it turning on???? Must I be shorting to ground somewhere?

sotb3

do you have it installed yet and if so is it connected to the body via metal? even if so i would still run a good ground for noise suppression--

Cellar

Yes and no for all intents and purposes.

Seems as though the antenna ground is completing the curcuit for the unit to turn on.

Is this normal?

This didn't seem to be the case when I had it installed in the other truck. (as stated in the above ground problem)

The only other idea I had was that the antenna ground in the other truck was no good. The CB (transmit and receive) worked fine though.

Here is a picture of my install method (inspired by this site) The red wire is power and the black is supposed to be the ground wire that completes the circuit for it to work.

sotb3

i guess what i'm saying is possibly your ground is thru the chassis of the radio to the same of your vehicle, or did you have the same stup on your other rig? i know my toys are all mounted to plastic and so need the ground--i think it is possible to ground via the antenna but i'm not sure that's a good sign for the working of the unit--

Cellar

Well the CB housing is plastic (the back is metal where the antenna plugs into) and the CB is mounted into plastic.


I tested it:
1) with the black wire NOT connected and the red wire connected to +12V with the antenna cable connected.
Result: The CB unit was on.
2) Same as 1) with the antenna cable disconnected.
Result: The unit was off.
3) with the black wire connected to a ground point and the red wire connected to +12v with the antenna cable connected.
Result: The CB unit was on.
4) Same as 3) with the antenna cable disconnected.
Result: The CB unit was on.

My thinking is that if 1) or 2) is true, the unit should be off.
My thinking is that if 3) or 4) is true, the unit should be on.

Anything else indicates a problem.

Is my thinking correct?

sotb3

yeah, it definetely sounds like your antenna is grounding the whole unit--what i was referring to before was the grounding that comes from the radio chassis which is metal, through your mounting thumbscrews, on to your metal mounting bracket and then into your vehicle(if that was metal), but your pic didn't pop up until after i wrote back to you, sorry--main thing is just check your antenna with a rf meter and you should be good--luck--

firemaniac

Did you use the original thumb screws to hold the radio in place?
Sometimes if the thumb screws are to long they can contact the electronic boards inside the unit, at the least cause undesired operation, and at the worst damage the radio.

Try removing, or at least backing out the thumb screws and try the radio again.

Cellar

Yes, the original thumb screws are used but on taking the unit apart, I think there is sufficient clearance for the screws. I'm just not sure if the unit is supposed to be grounded through the antenna ground or not.

8 T 8

Def. a ground via the antenna. I've seen this happen with tape and cd decks I've installed over the years.

Cellar

Sorry to quote myself, but the question still remains...

Is there no problem?

WILLTHISIFSGOHIGHER

Sounds like you might have a case of the Toyo-Ghosties I once had the same thing happen to me but my cb wasnt even connected to power.......

Tacomolas99

Do you remember which thread showed you how to install the cb this way? I don't want it on the top of my dash. Plus I'd like to see what kind of antenna is best to use and WHERE to put it. I put mine at the base of the windshield to hide as much antenna cable as possible, though I know the best place is the roof...I can't afford a professional install (drilling a hole in the roof, hiding all the wires, etc)

...Oh and thank you very much, in advance. I'm sorry I can't be of assistance with your issue right now!

Cellar

Right Here

Tacomolas99

Too awesome, thanks Cellar