I used 3m 'Scotchkote' to coat the whole shebang - it waterproofs it ok
you can get it in the electrical section of Home Depot or Lowes, etc.
but both your suggestions sounds good - Silicone would be my chouce of the
2.
other things to try : 3M 'Scotchfil' (its like a rubber putty) then cover
with 3M 88 weatherproof tape.
and of course - we can't forget epoxy (but it will crack in time)

"SpamHog" wrote in message
om...
I have a low-power 4:1 toroid balun almost ready in a little plastic
box. In order to keep the rain out, I am sealing everything up, but I
am also considering space-filling materials.

I am leaning toward filling it with hot "wax" - actually, paraffin
from standard household candles, although a harder grade like
sometimes found in old military equipment should be better.

The pro should be that the box would not become sealed for eternity in
case I want to re-wire something in the future, while epoxy is bomb
proof, and urethane foam is also rather hard to remove.

Is there any electrical con to be considered?


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