"W3JDR" wrote in news:OiLzi.1550$OM1.1000@trnddc07:


There's always moisture inside the trap when I disassemble the
thing, so I'm wondering if maybe I shouldn't be trying to tape up
the traps at all - maybe they are retaining water or something that
is affecting the capacitance. Each trap has a drain hole at the
bottom, and the aliminium pole itself has drain holes every now and
then that I'm trying not to interfere with.


It's very difficult to hermetically seal a large surface-area
container from moisture ingress. What happens is that, on a warm sunny
day the container heats up, causing the inside air to expand ,
pressurize the container somewhat, and leak out. Then a thunderstorm
blows in and cools the container suddenly , causing the inside air to
quickly contract, pulling a vacuum and consequently sucking in some of
the humid outside air. The humid air that was sucked in then condenses
back to water, which remains trapped unless some reasonable size
'weep' holes are provided at the lowest point.

The moral of the lecture is that, unless you have taken substantial
measures to guarantee a hermetic seal, you should have drain holes.

Now that was an original though posted in response to my post!