CB grounding

[Spook50]

The manual for my CB says to either ground it directly to the battery or to the chassis, but I'm wondering if one way is any better than the other. Would it be a good idea to ground it at the same spot as the antenna?

Am I just overthinking it?

 

[1911]

If you're talking about the power wires, it's better to take both (including the ground) straight to the battery; less chance of RF noise that way. Twist the power wires as you go too.

 

[Mark W]

1911 is right. But you are also overthinking it. Unless you have really reworked your CB and are pushing raised output... it is like... well as the V8 guys like to say about the 2F... polishing a turd.

A box stock CB will not care much where you ground it so long as you do.

And grounding at the antenna location does not hurt or help anything at all.


Mark...

 

[Spook50]

1911 is right. But you are also overthinking it. Unless you have really reworked your CB and are pushing raised output... it is like... well as the V8 guys like to say about the 2F... polishing a turd.

A box stock CB will not care much where you ground it so long as you do.

And grounding at the antenna location does not hurt or help anything at all.


Mark...

Yeah I followed his suggestion of connecting directly to the battery and twisting the power leads (a vise and a DeWalt work great for twisting a full 20' length of 14awg wire ). I'll have to finish the CB install at a later time though thanks to moving and a two week TDY right after, but for now I've got both the power and antenna wiring run, so install and tuning will just be a couple-hour affair one afternoon.

 

[MBOffroading]

I planned on mounting my CB today, after reading this, if I understand it correctly, I run both wires (pos/neg) twisted to the battery and connect them directly? How would I power off the CB when not wheeling?

(first time installing one)

 

[Bogo]

I planned on mounting my CB today, after reading this, if I understand it correctly, I run both wires (pos/neg) twisted to the battery and connect them directly? How would I power off the CB when not wheeling?

(first time installing one)

You could insert a normally open relay into the supply wire that is activated by the acc circuit. Note: your radio may want a second positive wire for powering it's backup memory. That wire could also be wrapped along with the others.

When wrapping wires it is preferable to hand wrap them. Also put them into a loom. Wrapped wires, when they abrade up against something, are much more likely to short + to -.

 

[MBOffroading]

Thanks for the info, I'll have to check it out tonight when I go to install it.

 

[Spook50]

I planned on mounting my CB today, after reading this, if I understand it correctly, I run both wires (pos/neg) twisted to the battery and connect them directly? How would I power off the CB when not wheeling?

(first time installing one)

What's been explained to me is that if you want minimum noise you want to go directly to the battery terminals. Hopefully this won't create a parasitic power drain (doubt it since my Uniden uses a hard switch for power), but if it does I'll install a toggle switch in line with the power lead (maybe a fancy custom JIS switch with a radio emblem on it ).

 

[MBOffroading]

I noticed that after I installed the CB, I have a 'hard switch' as well, so maybe going straight to the battery is a good idea.

 

[brew8]

The battery acts like a large capacitor and tends to filter noise, the twisting wire helps it to resist induction, a few more things you can do is a good tuneup with resistor plugs and good wires to resist arching outside of the combustion chamber, also make sure you don't have leaky diodes in your alternator, you can put a voltmeter across the output set to AC volts you should see only a few millivolts of AC any more and you likely have leaky diodes and need to replace them, HTH Larry

 

[Bogo]

the twisting wire helps it to resist induction,

Actually only well grounded shields do that. Twisting the wires will make it so any current/voltage that is induced into the wires effects both wires roughly equally. This means both positive and negative wires will have very nearly the same current/voltage induced into them. It helps for poor input power stages in the radios.

 

[Tools R Us]

1911 is right. But you are also overthinking it. Unless you have really reworked your CB and are pushing raised output... it is like... well as the V8 guys like to say about the 2F... polishing a turd.

A box stock CB will not care much where you ground it so long as you do.

And grounding at the antenna location does not hurt or help anything at all.


Mark...

Agree, mine has been wired to my power seat circuit for years. The only time I get any noticeable interference is when adjusting the power mirrors.