SWR,Antenna questions

Thanks guys,
I talked to the tech where i ordered the radio.He said 8 AWG should be fine for that radio.Just be sure to use a quality copper wound wire.
Not the Chinese made junk.
I found some at a car stereo shop that they use to run those big stereo amps.
Did some looking at the truck and decided to run it from the battery under the cab,through a rubber grommet in the firewall and up the a-pillar to the overhead.
Fuse it at the battery and should be good.

 

I used to have a 667.....wish i would have held on to it. It would dim every light in my old Freightliner...lol!

 

Since you have tried a different coax take a close look at the stud on the antenna mount.
Be sure that plastic ring is intact and the antenna is not grounding out on the mount,
Also check the back of the radio where the coax screws in to be sure it has not worked loose inside the radio.
Next step would be a bench test of the radio.