Re: Tarheel SWR suggestions wanted


Paul Butzi (W7PFB)
 

I think you might have some common mode current problem.

If you have enough coax length, make the coax connected to the mag mount into an ugly balun by putting a bunch of 6” diameter loops in it, hold them together with zip ties.  Maybe do that with the longer coax that runs to the amp, too.  Also, grounding the base of the magmount to the car frame or some other serious ground might help.   Maybe just do all three and see if it helps, it doesn’t take long to put loops in coax and attaching a wire to the magmount and to a ground is probably pretty quick as well.

Also the fact that you can operate for a bit and THEN the swr jumps up makes me suspect that there’s some component heating issue.  Maybe the bnc barrel is not rated for the power you’re putting through it?  How much power are you running again?

-p W7PFB
73, Don’t forget to smile and have fun!

On Feb 26, 2021, at 1:17 PM, Robin WA7CPA <wa7cpa@...> wrote:

Hi Ralph,
No dummy load with me but when I get home I can test cable. So, I've put 2 cable on and both had same SWR results at both ends.

Robin

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