cb wiring question

I have a 97 dodge ram that I am installing a cb in the overhead console in. My question is since it is only a 4 watt max cb would it be safe to just wire the cb into the dome light wires up in the console? My ALLDATA program says the lights are powered by a 5 amp fuse would this be enough to handle the load of the cb ?

 

[Nasty350LT1]

Just look at the rating of the inline fuse on the power cord of the radio.
This should answer your question.

 

[pickupman]

assuming 50% efficiancy (lowball figure), 4W / 12V = .333333A * 2 (the 50% part!) = .6667A on full transmit. this should work for you, HOWEVER: make sure you have a separate fuse on the radio (between the light and radio) in addition to the one inline with your light.

you should also keep in mind that there MAY be some electrical noise (alternator whine, etc.) in those power lines. the only thing you could do to it at that point would be to run a completely separate power wire from the battery

good luck, and post pictures!

 

[FreeWheelin4x4]

I'd personally put it on a separate power source such as to the batter with an inline fuse. This is of course personal preference.

The alternator whine you could probably get a filter and put it on the power wires to help out with that. I don't know how much noise those lines produce as I always wire things individually to eliminate needless troubleshooting in the future.

I'm sure you could get away with wiring it to your lights, 4w is the max that radio will push out. CB is AM band and modulated by voice as opposed to frequency so your output could vary (depending on the solidity of the unit).

Just my .02 worth

Yes pictures please It'd be interesting to see the set up once finished.

 

[Sandy]

As you have heard before yes it will work.

The CB only draws it full current when transmitting and then just make sure the interior light isn't on.

As stated before there is the possibility of noise and then getting rid of the noise can be a problem.

To wire to teh battery you would only need either two 18/16 gauge wires or a piece of RG8X coax (center - power, outer shield - negitive) to run from the battery to the overhead console.

If you run the wires to the battery make sure you add a fuse in-line on both wires as close to the battery as possible.

Another plus when running the wires to the battery, you could run a larger gauge wire than neeed and terminate it near the inside firewall using a terminal strip. Fuse the wire at the battery, when you need power for anything you can tap off the terminal strip, fusing your component separately.

Luck,

 

[pickupman]

Sandy-

I have to say, turning a piece of Coax into a shielded power cable is an interesting ides (hadn't thought of that one before)... I would think for a 4W radio, a piece fo mini-8, RG58, or even RG59 would work fine.... discussion? I knwo both 58 and 59 are rated for some pretty high VOLTAGES (used 59 for a 3kV amplifier high voltage line, IIRC), but haven't seen any sorts of current specs for them....

and one does need to be SURE that the entire shield is isolated from the center conductor.... sometimes that proves to be one of the more difficult tasks when using coax for something other than RF and RF connectors....

 

[Sandy]

Pickup - I do not know the current rating of a piece of coax but I have used that method for CB and Scanner Power for longer than I want to remember.

Yes the separation of the center to the shield can be a problem but as long as there aren't any shap corners then it will work out.

I used to use the RG-8 but when the RG-8X came out it became my power cable choise. Thinking about it, a solid insulator might work a little better for separation but I like the foam, just need to use some caution, maybe I should have stated that.

Although I have never had a CB/Scanner power line short out.

Later

 

[ryf]

there isn't a problem with the using the Rg-8 as power wire on low amp projects... just remember with a solid core wire, it can be more apt to breakage if you were to route it in such a way as to cause excessive vibration, or pulling, such as routed outside the cabin area, pulled between frame and body. It could service that way for months or years, but solid core wire won't last as long in that situation as twisted strand wires would.

I'd say its a cool idea, and worth looking into especially for ease of routing, if nothing else, just watch how you run it if its going through any flex points.


this would be true with your antenna's RG-8 so keep that in mind as well.