I just bought a Cobra 18 WXST II cb radio off of Ebay. The reason I liked it was because it included being able to scan the 10 NOAA weather channels, and it has a front-firing speaker.

For a quick hook-up, I decided that I would stop by radio shack to buy a cigarette-lighter 12v adaptor.

The problem I am having is that the CB has 3 wires - 2 positive and 1 negative (ground). The adapters at radio shack are made to accept only one of each. Upon inspecting the CB radios that were in the store - the store employee and me found that they all had 1 positive and 1 negative. He said that my radio must be old. He told me that I could simply hook one of the positives and the negative to the adapter, and cap off the additional postive wire. Is this true? If it is, which of the two wires do I need to attach to the adapter?

The instructions with the CB say that one of the wires (red) should be attached to a 12 volt accessory fuse, the other (orange) to a constant 12v fuse. I will do this in the future for a permanent installation, but am very short on time and would like to use the 12v outlet adapter for the time being.

The only thing I can think of is that this is like a car audio amp - a constant power source, but being wired with an accessory wire in order to only receive power when the vehicle is on.

Your help is appreciated.

hook both 12v positives to the positive on the plug (usually center pin IIRC) and the ground to the ground.