4x4 - Home

Cobra 75 WX ST CB Radio Installation


The Cobra 75 WX ST is a 40-channel CB that requires a very small footprint.  The complete radio fits in your hand making it ideal for compact installations. It also provides you with 10 NOAA National Weather channels, full channel scan, dual watch, and an illuminated LCD display for easy viewing. This is an extremely popular radio with Jeep and off-road vehicle owners as it takes so little space and is much more convenient than mounting a traditional full-size CB in a small cab. The handset is connected to a small mounting/interface box that can be tucked under the seat or dash for a very clean installation.

The remote mounted interface box provides fused power, an antenna coax connection, a jack for an external speaker, and a connector for the handheld radio unit.


Bob was in charge of figuring out where he wanted to mount the interface box.  After we checked the passenger seat for adequate clearance, we used a couple of self-tapping screws and located the interface box on the lower right front corner of the center console. 


Power to the Cobra's interface box was obtained from the unused Aux Power fuse socket in the fuse panel behind the glove box.  On my '98, that same Aux Power is provided by a labeled wire that is tucked back into the wiring harness behind the glove box. 

I'm usually not one that is prone to tapping into a fuse box for power to run an auxiliary item such as a CB radio.  However, this fuse socket was not in use (did not even have a fuse in it) and so Bob sprung for the fuse adapter at the local auto parts store.  I crimped an insulated connector onto the of the adapter wire and put the corresponding connector on the positive (RED) power lead of the interface box.  Needless to say it was a quick and easy way to get 12 volts for the radio.


I crimped a ring terminal onto the negative (BLACK) power lead of the interface box.  The glove box is framed with a metal support which makes for a satisfactory power ground.  After removing one of the mounting screws, I slipped the ring terminal over the hole and reinserted the screw.  That wrapped up the power requirements for the Cobra radio.


The remainder of the radio install consisted of drilling a small pair of holes for the external speaker's mounting bracket.  We were somewhat at a loss as to exactly where to put the speaker.  This location will interfere a bit with tumbling the front seat fully forward.  We needed to get the install wrapped up and Bob decided to use this spot for now and he would work on finding a more favorable location. 

The power leads and speaker cable were both routed under the center console (passenger side) to keep them out of site and provide a degree of protection for them on their way back to the interface box.  I used a short length of plastic wire conduit to cover the wires between the interface box and the console.  Doing so provides another measure of protection and makes for a more professional looking installation, in my opinion. 

With the speaker and interface box in place, Bob connected the radio to the connector on the interface box pigtail.

More Cobra Off-Road Kit



4x4 Off-Road    Homestead    Firearms    RC Flying