The following cautionary tale from a long-time 100-watter who just
graduated to relative QRO last spring:
The weatherproofing practices that work fine at 100 watts just won't cut it
at QRO. Within the last 2 weeks I've had to fix two connector problems in
my HF antenna system. In both cases, there was tangible water inside the
connector. Now, I've noticed this before, at lower power, but without
measurable ill effect. But in these latest cases, the water was
accompanied by visible evidence of arcing -- sooty deposits -- and a
shorted reading on my ohmmeter. In one case, a barrel connector, the soot
was readily visible, and once I cleaned it out the connector was fine. In
the other case, a PL-259 with adaptor for RG-8X, it couldn't be seen till I
disassembled the connector, and the only cure was to reinstall the connector.
So while I don't go to the extreme of the "3 layers of 88, vapor barrier,
two latex condoms and another two layers of 88" crowd, something more than
carefully applied double layer 33+ seems indicated for reliability's sake.
73, Pete Smith N4ZR
n4zr@contesting.com
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search
|