This happens to me about every other year. Usually right before CQ WW SSB
as the weather gets colder through October (here in Vermont the night time
lows are into the mid 20s by then). Its always a braid to connector joint
that has worked loose through a number of years of temp cycling and the last
few threads have broken the solder joints. So as the connector heats up its
making good contact - good SWR - good initial receive. And then the receive
noise floor drops away and signals drop by 10db as it cools back down.
Sometimes hard to find "the one". My radio feedlines have 2 connectors on
the LDF4 from the bulkhead at the house entry to the back of the radio.
Then 2 PL259 connectors on the jumpers to the LDF5-50. Then another jumper
from the LDF5-50 to the switch box at the tower. Its easy to tell if its
not antenna specific. If its antenna specific, it's a similar dance.
All part of the game up here in Vermont.
Ed N1UR
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|