Topband: Connector grease

[Tom W8JI]

> FYI Bill....the use of medical grade petroleum jelly was recommended
> in ON4UN's LBDXing book.  That doesn't always make it right, but
> personally,
> I've been using the jelly for years to keep water out of connectors and
> it works very well.  The tube of the jelly works great as an applicator
> rather than from a jar.  I fill the connector completely, leaving no
> voids.

I would not use petroleum jelly on any electrical connector, especially to 
flood it. That is bad advice, no matter what source recommends it.

I also would not fill or flood a high power transmitting connector with 
anything, even pure silicon dielectric compounds that are engineered for 
electrical applications. I especially would not use some crude hydrocarbon 
based grease that liquefies at low temperatures (I think around 100F)  and 
spews flammable vapors that attacks rubbers and some plastics.


Things that do NOT belong on connectors are generally things that are 
petroleum based, like noalox, anti seize compounds, and so on. Also keep in 
mind, connectORs are very different than bolted connectIONs. Something that 
works on a 2000 psi clamped cable connection that is out by itself can 
behave a whole lot different in a 20 psi spring pressure contact that is 
adjacent to opposing polarities.

Besides silicon dielectric compounds, there are some very good synthetic 
greases now suitable for connectors. There is little reason to use things 
that have been known to cause problems when there are so many other less 
troublesome choices. I know Hams pride themselves in being cheap, but I'd 
just spend ten bucks for a tube of the right stuff at any auto parts store 
or almost any home improvement store. It has a temperature range of -40 to 
+500F, won't emit flammable vapors, won't carbon track, and does not attack 
any plastic or rubber.

73 Tom