On Sat, 05 Mar 2016 21:10:59 -0800, DaveC wrote:

Jeff Liebermann wrote:

Dielectric means "insulator" in this case, which is not exactly what I
would want in an RF connector.

Jeff, I think he means he uses it under the boot, not inside the connector…
Dave

Yep. "...under the weather boot to keep the oxidation down". My
apologies for expanding the topic, but I assumed that connector
performance was more important than surface cosmetics.

The problem with petroleum based greases, such as GC 10-8101 which is
about 10-15% mineral oil, is they cause the rubber boot and F
connector O-ring seal, to swell and possibly deteriorate depending on
rubber composition. I must admit that I've never seen it happen where
it can be easily attributed to grease because nobody around here
covers the outsides of TV/CATV/TVRO/DBS connectors with grease. For
more expensive RF connectors, where water incursion is a problem, I
wrap the connectors with PTFE tape followed by a layer of electrical
tape. Then some clear acrylic spray to reduce UV deterioration.

Another problem is that greases like to migrate when warm. I can
usually tell when someone has stuffed a connector full of grease
because the grease eventually appears on the outside of the connector
where it accumulates dirt and dust. Capillary action also works for
viscous fluids, like grease. I've been told that F connector threads
are designed to be a rather loose fit to handle expansion caused by
corrosive products (aluminum oxide) and not jam the threads. If true,
such threads would not make a very good seal.

The phone monopolies have the same problem with outdoor NID (network
interface device) boxes, which have at least one RJ11 connector. The
gold connector wires can take care of themselves, but the copper flat
ribbon cable that connect to the RJ11 are a problem. Instead of
grease, they use a very viscous polydimethylsiloxane (silicone) gel to
seal the connector area. There's a tech description near the bottom
of the patent:
http://www.google.com/patents/US6971897
A gel doesn't run when hot and doesn't seem to attract dirt because
it's fairly non-sticky. Note that all the references at the bottom
are for a "gel" compound, not a "grease".




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