[TowerTalk] Help Solving Problem with Inv-L Antennas

Eric Rosenberg wd3q at starpower.net
Tue Feb 19 00:10:17 EST 2008


This past weekend, my preiously excellent Inv-L's (80 and 160) wouldn't 
take more than ~90 watts without locking the transmitter.  RF feedback.

The only difference I can come up with is that we've had *big* winds 
here of late (gusts to 50 mph). The trees swayed as I've never seen them 
before. Although we've also had a bit of rain and even less snow, the 
connections are well sealed (or so I think) and have been so for some 
time now.  The 160 vertical element is anchored to the tree support, so 
the connection to the RF connector is not strained.  The 80 vertical 
element goes directly to the connector (a Budwig center conductor), but 
there's enough slack on that antenna that anchoring isn't needed.

Neither came down in the winds, and the SWR didn't change (very low), 
not that SWR is necessarily an indicator of performance.   I suppose I 
could replace the respective feedlines, as there might have been water 
migration, although I'm not sure what the indicator of water migration 
is and ow I test for it? 

Thoughts?

EricW3DQ
Washington, DC


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