James,
When I'm weather sealing baluns, it depends on what the purpose of the balun
is.
For use on sturdy masts, I do it like everybody else does, and place
everything in well sealed plastic enclosures.
I'm luckier than most guys; I have hundreds of balun enclosures. I have so
many that I have to sell them! (hi)
But, the real challenge is building lightweight baluns for use with
lightweight telescoping fiberglass poles.
The pole is very thin near the top. In order to get maximum useful height
out of the system, you have to do everything as lightweight as possible.
I try to only use toroids from Ferroxcube, not Amidon.
The ones from Ferroxcube that I use have an Epoxy coating on the surface,
which in itself is waterproof.
If I have to use Amidon (Fair Rite) cores, then they get lots of liquid
electrical tape coated onto them after they are completed.
I only use Teflon insulated wire, then I work a lot with heat-shrink tubing,
but a special version with glue inside, so when it shrinks, it really sticks
in place. Finally, after it is assembled and (very important:) tested as
"good", I apply a layer of liquid electrical tape over everything except the
SO-239. The result is a very lightweight but well insulated balun.
These links show some pictures of various baluns I have built:
.. http://www.dj0ip.de/balun-pictures/ ..
.. http://www.dj0ip.de/cmc-test/the-baluns/ ..
Some are shown there not yet coated with liquid electrical tape.
I did that so that people can see what they look like under the black goo.
BTW, when I'm testing new ideas (which often fail - but not always), I don't
bother with the liquid electrical tape. I just test them by nice wx. That
way if I have to change something, I can. Once you encapsulate it in this
gooey stuff, it's difficult to change anything.
The results are, I have built entire aerials which weigh less than one
pound, including 40 ft. of lightweight coax.
FINE for portable operations up to about 150w.
Pictures of these are found under "Off-Center-Fed Antennas" on my web.
When building these baluns, I follow the guidelines Steve has on his web
page, here:
http://www.karinya.net/g3txq/chokes/
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Richards
Please remind me what you did to weather seal the toroids
------------------------- K8JHR -----------------
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