I’m testing a yagi... I can raise it to ~37’ for testing and lower it to about
8’ for adjustment ... it was made as a duplicate to another one and testing
showed it to be just that – a duplicate. Until it rained! The SWR shifted
downward. At 21425 it was ~1.35:1 ... and it would go over 2:1. I’m at a loss
as to what is causing this. It is a used antenna reassembled... but I find it
very difficult to believe that water could get in to the mechanical joints and
cause this kind of a problem. The balun doesn’t appear to be taking on water –
there wasn’t a drain hole in the bottom – there is now – I went out early this
morning just after it rained – SWR up high – and there was nothing coming out
of the drain hole. I have checked all connections – they’re tight. Oh – and the
strange thing – it goes back to normal after only about 4 – 5 hours without
rain. It has done this 3 times now. It is now – 45 minutes after checking it
this morning where it was at 2.33:1, its now down to 1.8:1 and continuing its
decent. And further note the SWR seems to be about the same – its just shifted
downward when wet. Also I hosed it down – the balun/coax connection, hairpin
for a good 5 minutes – no change. I hosed down the elements at their joints –
no change. It rains: changes! The fact that it shifts seems to be independent
of height – it does this if at 37’ or at 8’.
Also: is Noalox the same as penatrox? It is the No AL OX sold by HD ... it says
it is for increased conductivity as well as anti-seize... perhaps IT is the
problem at the joints ... unless someone knows it to be fine (or KNOWS it to be
bad).
thanks – I’m hoping someone has personally seen such a thing and has an idea.
Its holding up the testing of the other antennas.
Gary
ps: the first one had no problems when it was rained on.
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