I have Cobra LTD29 BT. 8" cable. Do i need longer? Some reason i cant get it tuned in on 1,20,40 SWF. Sometimes it does then its off, i have a set screw in my whip i can adjust but it always off when i recheck when i am out. I am a new CB user so i want to do it right. Anyone in AZ that can tune this and set it up right for me, contact me. Had it for my recent jeep run but didnt want to talk on it and burn it up.

 

If all the coax you have is 8 feet, by all means get some that is 18 feet.
That s why it wont match right.

 

When you say "sometimes it is..then its off" what do you mean? Does the SWR change?

How are you measuring the SWR? Are you near a building or in a garage? Are the doors open?

The best way to tune an antenna is to take it somewhere away from anything (like in a large parking lot). Then make sure the doors are closed before checking the SWR. HF frequencies are so picky that all these things can effect it.

B