Today looks like Antenna problem day... here's mine:
40 Meter antenna exhibits shift in SWR. Setup is FT-990/AL-1200,
ICE filter, run to antenna switch, then thru Heath tuner to
402BA. SWR at XMTR looks fine, then shifts to about 3:1
without notice. Occurs at low power. If I turn on the amp
and apply about 1200 watts to antenna, the SWR suddenly comes
back down to 1:1. Tried the usual, replaced cables inside,
moved position on remote switch, looked at tuner innards.
No obvious signs of malfunction.
Other possibles, linear loading has "growth" on it that high
power cuts through ?, but problem does repeat itself, coax run
has problem ?, both will require use of cherry picker to reach,
unless I can round up a crew to take everything down.
Any suggestions from the group.
Thanks, Dick, W1KSZ
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