I'm surprised nobody mentioned the possibility of a balun failure.
If you are using a balun, replace it when you're up the tower.
Don
N8DE
Steve Lawrence wrote:
> SUMMARY response:
>
> Puzzle: Intermittent Hi SWR when barefoot and down to QRP levels on a
> TH7 but only on 20m. Clears when hit with legal limit power and then
> returning to LP.
> .
> Signal path: rig-amp-pwr meter-ant switch-coax-TH7 (w/BN4000 balun).
>
> With rig connected directly to a dummy load, SWR is normal but the
> problem continues to appear when rig is connected directly to the TH7
> coax.
>
> Others have had similar experiences narrowed down to the only 20m
> unique part of the TH7's DEs: the clamp on the element tip and / or
> the far end of the 15m trap. Cured by tightening.
>
> Looks like a trip up the tower is called for.
>
> TKS to: K4SAV, W4EF, N2TK, K1IR, N8CC, WA6TLA, W5AH and anyone else I
> may have left out.
>
> 73 - Steve WB6RSE
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
> _______________________________________________
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>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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