KW T680 stock coax help

well if the ends have been cut off you need new ones..Gonna have to get a good cb shop to do that..OR run some lmr 240 yourself with ends already on it

 

You'll need a couple of these and a couple reducers..

https://www.dxengineering.com/parts/dxe-pl259
$2.75 each plus the cost of the reducers

 

Well, if the coax cables are really RG 59/U then both of those 70 ohm cables need to be co-phased. That will require a co-phased wiring harness to connect both antennas to the radio. If using both antennas and they are not co-phased, the mismatch will cause all kinds of havoc.
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. Simple solution: run your own 50 ohm coax (RG 58, RG 8, Lmr something or other or similar 50 ohm resistance cable) from only one of the antennas to the radio. Route the cable through the truck or be lazy like me and just route the cable through the driver side window just make sure you do NOT close the window all the way up and crush the cable. It may look like [bleep] but I don't care.