CB Installation Tips

[+ d]

i am getting ready to install my new CB (cobra 75 wx st/wilson lil' wil) and was planning on running the antenna cable to the rear so the mag mount can be placed on the back center of the roof. i think i am going to have the cable exit through a rear hatch grommet and splice in a quick disconnect so i can remove the antenna when not in use. since i will be tearing apart my interior front to back (not fun) i was thinking i would lay some 4ga cable for a future rear power distribution block...

is it potentially problematic to have power run parallel to my antenna cable?

any other general installation tips that might make this thread helpful to others?

[pskhaat]

is it potentially problematic to have power run parallel to my antenna cable?
any other general installation tips that might make this thread helpful to others?

Generally you shouldn't have much issue with the power line as its DC vs the AC in the coax, but why risk it if you can separate them?

That quick disconnect will alter your effective radiated power as well as your impedence, so make sure you get a good match on SWR throughout the whole system.

And post some pictures

[goodtimes]

As a general rule, it is better to seperate them...but as already mentioned, you don't have the EMI problems with DC. If you ever plan on adding a different radio (say, a 2 meter), you will want to run that cable separately, on the other side of your vehicle if possible. Also, if you are going to run any AC wiring (say, for a inverter located in the front, to a outlet located in the back), you want to keep those separated as well.

[+ d]

thanks for the input guys, just to play it safe i will run them separate.

I'm not sure i know what this means though...

That quick disconnect will alter your effective radiated power as well as your impedence, so make sure you get a good match on SWR throughout the whole system

i thought i just had to check the SWR at the antenna to radio connection...? i'm new to this CB stuff so i guess i'm not understanding how i would check "throughout" the whole system...

[Bluto]

Sorry for the Hijack.

Im thinking of making my cb interchangeable between vehicles (along with my mag mount antenna).

Right now its wired to the batttery for power in my LC. To make it easier to use on my other vehicle can I use this (below pic Radio Shack) for an ez source of power on that vehicle therefore avoiding a hookup to the battery (ez install)? Is this advisable? Or just buy another cb. Thanks for the info.

Radio Shack Power Adapter (connects to the lighter) with Banana Plug with red and black connection

[Scenic WonderRunner]

I've used adapter plugs like that for years with no problem.

But if you start plugging into your lighter sockets and start getting "engine noise"......you can always bring a battery direct 12V socket into/under your dash and you then still have a direct battery connection.

Always use fuses!

Did I explain that right?

I wired one of these (direct from battery) in the pic for my back seat passengers. I put it down in the passenger side "Elbow Pocket". This pocket is movable, so I left extra wire down under it so I can move it around toward the back of truck while camping.






If you want more outlets. You can get something like this. Cut off the PLUG and use it on your CB. Then make a direct battery connection with the right size gauge wire and mount it under your dash. I would prefer a triple that comes with plug hole covers.......this is just an example.

[pskhaat]

Sorry, didn't mean to be so unclear:

I'm not sure i know what this means though...
i thought i just had to check the SWR at the antenna to radio connection...? i'm new to this CB stuff so i guess i'm not understanding how i would check "throughout" the whole system...

Any connector between the radio and antenna causes power loss and changes the RF impedance (kinda like DC resistance) (the coax does too, but only so much you can do). In AC/RF circuits, you try and `match' the impedence at all points. Some things like kinks in the coax, or 90deg adaptors may add (or subtract if you will) impedence in the system. Thus you may get a great SWR when measuring it at your radio, but you could get different SWR measurements throughout the whole feed line (like at the connectors) up to the antenna. Some parts of your feedline may be 40 ohms, others sections may act like 60 ohms, but in aggregate you see ~50 ohms (what CBs usually expect), just means your system isn't efficient and thus you loose power.

All I was saying is check your SWR at each of the connection points to see if you are loosing efficiency along the way and it's just not reporting itself back at the radio. Generally I ain't that anal about things , but it's really easy and timeless to do, so...

[Bluto]

Always use fuses!

Did I explain that right?

Yes. Fuse prevents electrocuting electronics.

Thanks Scenic.

[asteffes]

For high-current connections such as those for lights or radio gear, I suggest using an Anderson PowerPole connector. They are not subject to the noise problems that lighter plug connectors can suffer from, and are offered in sizes appropriate for heavy gauge wires that you might use for lights or inverters and such.

You can find them at http://www.powerwerx.com/

[pskhaat]

I remember also hearing somewhere that the PL259 type connectors (like those on a CB, etc) were actually designed for a DC power plug!