On Mon, 12 Jan 2009 21:57:52 -0500, "NoSPAM"
wrote:

Also I would like to add that the Krylon sprayed over the vinyl tape is
very important. Being an acrylic, clear Krylon protects the vinyl from
ultraviolet damage.
73, Barry WA4VZQ

I've been waterproofing RF connectors using 0.5" wide PTFE tape to
embalm the connector. The PTFE will eventually cold flow, forming a
water tight seal. The PTFE also prevents capillary action from
sucking water into the connector through the gaps, such as along the
outer knurling in UHF connectors. On top of that, goes a layer of 3M
Scotch 33+ electrical tape, which is claimed to be UV resistant. The
PTFE tape does the waterproofing. The outer PVC tape just holds
everything in place.

I've done some crude life tests on my roof at 2 year and 5 year
intervals. I found that when unwrapped, the connectors are a shiny
as they were when new.

However, I didn't think that PVC tape was porous and suffers from UV
embrittlement. After about 5 years, the tape does tend to be somewhat
bittle. I'll try some Krylon and see what it does. I'm a bit
concerned about adhesion to the shiny PVC tape and what will happen if
the joint is flexed. I dunno about spraying Krylon when I'm on top of
a tower. I'll let you know in about 5 years.

The no-fun part of semi-rigid coax and Heliax is connector sticker
shock. Connectors are expensive. I've been finding used connectors,
but that creates the problem of finding a replacement crush
(compression) ring. Some vendors supply them seperately, others
don't. I suspect the ones that don't, recognize that non-availability
of these parts creates a market for new connectors. I've had fair
luck using brass plumbing crush rings as a replacement crush ring. Buy
oversized and cut to size with a Dremel cutoff tool or blow saw. Brass
is really NOT a good idea for aluminum jacketed semi-rigid CATV coax,
but it should survive if kept dry.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558