Help needed with cb install.

[modelapickup31]

Hello,
I have a stock 6volt positive ground car with a positive ground alternator. I found this converter for 10 bucks at a swapmeet. Will this power my cb and if it will, does anyone have a diagram on how to properly install it?
Thank you,
Geoff

[glenn in camino]

I'm sure not an electrical expert, but that looks like the right stuff. I copied the way my other model As were hooked up by another club member and it worked.

[bobmc]

I have the very same set up in my 30 coupe. I drilled a hole in the seat riser pan and installed a cigarette lighter. That way I could plug in my CB or GPS when needed. Both of these devices have plug in connections.

On wiring, one wire is 6volt in, one is 12volt out, and the 3rd is ground to body. The coupe is not available to tell you which color wire is what but it will work powering your device.

Remember you only paid $10.00 for a part that cost over $100.00 retail.(Snyder's catalog).

Best of luck

[redmodelt]

Most CB's are going to be negative ground so you would have to isolate it and the antenna(?) from grounding to positive grounded car. I am not sure but it might need static suppression ignition components added to if anything like a car radio.

[Tom F OHIO]

I had an old 6 to 12 volt inverter for many years until it finally went bad. Bought a new one and had nothing but trouble with it. It even caused by car to quit a couple times. I went with a small 12 volt battery just for the CB and I can also run a GPS on it at the same time and its not tied into the car at all. Best thing I ever did.
Tom....

[modelapickup31]

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Will try this invertor first. The grounding part is the part that I'm unsure of.The spare battery route sounds like a great plan as well. Maybe I'll put a garden tractor battery in the trunk and run some wiring. I finished wiring the antenna last evening. The spare may help with the interference as well.
Thanks to all.

[Boston Bruce]

Originally Posted by redmodelt

Most CB's are going to be negative ground so you would have to isolate it and the antenna(?) from grounding to positive grounded car. I am not sure but it might need static suppression ignition components added to if anything like a car radio.

If that converter works, you won't need to isolate anything. The Model A ignition system is what it is and generates lots of interference. The CB radio operates on AM (amplitude modulation) so it's prone to a lot of interference as a result. It's like the AM radio in your car is subject to interference (static crashes) during a thunderstorm.

Get a CB radio with ANL (automatic noise limiter) and/or a NB (noise blanker). Both features are better than a radio without them but won't cure the static issue.

This is why Edwin Howard Armstrong invented FM radio...but that's another story.

I'd test that converter before installing it in your car.

[V4F]

cell phones are ez & better

[redmodelt]

"If that converter works, you won't need to isolate anything." Please tell us nobs, if the chassis of the car is positive ground and you attache the negative grounded CB/radio case to the body or other metal part how is that going to work out? If you install something in a positive car it has to be positive ground specific, does it not? Isn't that why you bought radios that were ether - or + or could be switched between the two. How does the converter isolate the - ground radio or CB from + ground.

[Bill G]

"Ground" is just a reference point.

For the charging system and other parts of the vehicle itself, the ground in reference to the rest is positive, which means that the hot wire is negative. With the converter, and in reference to the output of the converter, ground is negative relative to just that system, and hot is positive. As long as you don't cross the two hot leads, the grounds can very much coexist.

Therefore, the CB power would have its negative connected to ground, and its positive connected to the positive output of the converter. They are two separate "systems" with a common ground.

Same thing at home. The 110volt power has a common neutral that is an offset to the hot lead, but happens to be at "ground" or zero potential.

[redmodelt]

I guess as long as the chassis of the CB isn't part of the grounding it will work and as long as there is a negative lead on the out side of the converter.

[Bill G]

The ground wire on the converter is ground. Negative 6 goes to the input and positive 12 is on the output. Both are referenced to the common ground.

[modelapickup31]

Bill,
Should I splice the black output wire on the invertor with two black wires putting one of the wires to the frame of the car and the other to the black wire of the cb? I could tap into the wire that powers the interior light and use that as my feed for the invertor.
Thanks,
Geoff

[jmeckel]

The RED INPUT wire goes to the negative terminal on your battery, or to for example the wire that feeds your dome light. The black wire goes to the chassis of your car. On the CB side, the red wire (should be marked POSITIVE or +) goes to the red output wire on the converter, the black wire (or the wire marked NEGATIVE or -) goes to the car chassis. Yes you can attach both wires that go to chassis to the same point.

[Tom Wesenberg]

I have a 6 volt to 12 volt convertor, but you can't use a common ground for both voltages.

[Bill G]

Originally Posted by Tom Wesenberg

I have a 6 volt to 12 volt convertor, but you can't use a common ground for both voltages.

His appears to have a common ground. I would connect it as jmeckel posted. Also, with the photo of the hand holding the unit, the device looks quite small and does not look like it will take much current, so when it comes to transmitting using a CB, that unit might not take much power! I don't see any indication of the power limits on it, but it sure looks small. I don't think I would use a unit like that for much more than charging a cell phone, or at most, receiving a CB signal.

[RawhideKid]

*rolls eyes* Ok folk, let me explain what is going to happen when the CB positive wire is connected to this device and the antenna is attached to the bumper bracket or something similar.

The first thing you will see when plugging in the antenna is a spark when the sleeve is slid up to start the thread. This spark is not good as it will probably blow the 3 amp fuse inline with the inverter. If a larger fuse is used, depending on how large, it too will blow, or should blow. If this fuse does not blow, we are still not out of the woods because something else that is electrically smaller than the fuse will start to heat up, or just start to smoke, and once you let the smoke out.....well, you know, you can't put it back.

Now, most likely the smoke will come out of the CB, at which time you will have toasted one or all of the chassis to black wire connections.

Not to disparage the item purchased at the swap meet, but it may switch polarity and increase from 6v to 12v, but it doesn't change the nature of the CB. After years of repairing and installing CBs in everything from boats, motorcycles, trucks and off road team vehicles, I have seen my share of blown up CBs. The box may increase the voltage to run the CB, and most likely will stand the draw with a 3amp fuse, it will not isolate the antenna, and when you do isolate the antenna, you loose the purpose of the antenna as the CB needs a ground plain to function. Now, IF you insist on installing the CB, there are a couple things you can do to make it work, decent.

Install a separate 12v battery, any type you wish with at least a 5amp discharge rate, I recommend a motorcycle battery and hook the CB directly to that, and don't hook anything else to either terminal on that battery and install the CB as normal, Red to positive, Black to negative. Charge battery before using CB.

Another way to go is IF you have the headliner down, hook the center of the coax for the antenna to the chicken wire in the roof, providing you do not hook the shield to the car metal, the adapter should work. The CB MUST also be isolated from the car chassis. This will not be ideal, but it will function for basic short distance communication. Something else you might need is a SWR adapter to tune the chicken wire antenna as to not harm the output of the CB. Available at any HAM radio or CB store.

Just be damn sure that NOTHING of the CB is touching or attached to your car chassis.

[redmodelt]

Thank you. ^

[Richard in Anaheim CA]

Anaheim CA

[Jacksonlll]

Just hook up the + input to ground, the neg input to ground. That will power up the converter. Make sure the 12 v output + wire goes to the + on the radio. Neg to neg. If it is the cheap conv that i think it is, do not ground the antenna. Use an isolated magnetic antenna. I think this will work. I dont think the radio should touch ground either. Let us know how you make out and what starts smoking first.