[Elecraft] Strange SWR change on 20 at

[Dave Cole]

I added the SWR meter...  My actual SWR jumps instantly up about1 SWR 
unit...  I believe it is a bad connection on the Challenger where the 
main antenna connects to the 20 meter tuning stub...

Just sort of surprised me to see a second person with the exact same 
issue is all...  SWR change is instant, so it is not heating...  Happens 
at 30 watts, or 1 KW...  Time for a rebuild.

73s and thanks,
Dave
NK7Z
http://www.nk7z.net

On 05/13/2017 10:07 AM, Dave Cole wrote:
> Hmmm...  I am having the exact same issue...  My SWR changes after a few
> transmissions, then returns...  Up until now, I have been suspecting my
> antenna...  Time to add an external SWR bridge between the tuner and
> antenna as a permanent thing...
>
> 73s and thanks,
> Dave
> NK7Z
> http://www.nk7z.net
>
> On 05/13/2017 09:07 AM, Terry Brown wrote:
>> I recently started using my horizontal loop that is about a full
>> wavelength
>> on 80, for 20 meters.  I took down my yagi as we are moving; drat!  My
>> Horizontal Loop is at 40 ft.  height and fed with 450 window line into
>> a 4:1
>> voltage balun with about 15 ft. of coax to rig.
>>
>>
>>
>> I am running 100 watts through my KXPA100.  I tune a frequency in the CW
>> portion of 20 to about 1.2 :1 and start sending CQ.  After about 3 to
>> 4  3x3
>> CQ's,, the SWR goes off the charts and power drops to zero.   I can
>> retune
>> the antenna and the process repeats itself.  20 meters is the only band
>> affected.
>>
>>
>>
>> I am wondering if I am having RF problems in that part of the 20 meter
>> bands
>> This only occurs on 20 meters.  The Amp is grounded, but the KX3 is not
>> bonded to the Amp.
>>
>>
>>
>> I would appreciate any advice.
>>
>>
>>
>> Thanks and 73's,
>>
>>
>>
>> Terry de N7TB
>>
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