Won't some of these things interfere with the electrical conductivity
of the connection?
No. There is so much surface area involved that there's certain to be
a connection. Even if the grease were a perfect insulator and
conformally coats the threads, the capacitance between the threads
would be sufficient to conduct all but the lowest frequency RF signal.
It is the ground after all.
Sure. It's the RF ground. It has to pass signal at whatever RF
frequency the radio is operating. You could put a capacitor in series
with the ground lead, and it would still work.
Well, if you have a precipitation static or wind generated static
problem, you need some way to bleed off the accumulated charge, so you
will need a DC connection to ground. For such situations, there's
usually a large (1Meg) resistor across antenna connection to bleed off
the charge. Most radios have this built in.
It's got lots of area
to make contact on, so it probably won't have any practical effect,
but should we be messing up any electrical conductivity.
If it has no effect (practical or otherwise) it should work.
Incidentally, I recently setup a big battery backup system. An
argument ensued over whether to grease the lead battery posts and
hardware to prevent corrosion, or to leave them clean to maximize
conductivity. We eventually determined that compressing the
connection squeezes all of the grease out of the connection, resulting
in exactly the same connectivity with or without the grease.
Have you tried silicon tape, also known as shrink tape.
Sure. There are two types. One is a sticky on the inside type used
by the electrical industry. Incidentally, it's "cold shrink" and does
not require heat to shrink the tubing:
<
http://solutions.3m.com/wps/portal/...tions/Do-It-Yourself/AutoMarineRV/ColdShrink/>
I've used the stuff and it works. However, there are several
problems. The seal is the sticky goo on the inside. It makes a mess
and does not come off cleanly. You also have to get it right the
first time, or you get to start over. The thick sleeving does NOT
conform well to lumpy connectors or drastic changes in diameter. It's
very stiff and does not bend at all. Not recommended.
There's also conventional shrink tube, with no sticky goo on the
inside. This doesn't work very well. Without the goo, capillary
action sucks water up the interface between the coax jacket and the
shrink tubing. Not recommended.
It's much
thicker and is at least 4 dollars a roll, and and has a thin backing
that has to be pulled off, but after that, you stretch it to twice its
length or more than wrap it around and it pulls back, and sticks
really well to itself and other things.
I've used several versions of that stuff. One is like tar on a roll.
Wrap the connector with the stuff and it all sorta melts together. One
flavor forms a sticky mess that it totally waterproof, but impossible
to remove. Another variation allegedly just sticks to itself, and not
the connector. This has the capillary action problem, where water
creeps up the interface boundary.
After a while, a few days maybe, not sure, it turns in to one blob,
mummifying and waterproofing in one step.
If you want an irreparable blob, that's probably a good way to do it.
I prefer something that can be easily disassembled, doesn't suck in
water, can be flexed without opening a channel for water, and is
cheap.
The rolls I've seen look a lot like electical tape but have a white
plastic tube that it is wrapped on, not the paper tube that plastic
electrical tape has.
I think I have only seen this mail order.
Most electrical supply houses carry the stuff from various vendors.
It's "self-vulcanizing tape". About $1/ft. For example:
<
http://www.atomictape.com/atomic_tape_fact_sheet.htm>
The silicon version is sold in automotive shops as a "muffler
bandage".
That wouldn't be true of this stuff. Probably need a knife, blade up,
to slit the whole thing to get back inside.
But it's great stuff. Better than heat shrink tubing, much heavier,
and also able to be applied from the outside, wrapped around, when
there is no way to slide on from the end.
I'll confess to NOT having tried everything available. When I came up
with the 1" Teflon tape trick, I stopped looking as I had found what I
consider to be a universal solution. The biggest problem is using
inferior electrical tape to hold the mess together, or accidentally
using non-UV proof tape. The outside electrical tape doesn't do much,
but it has to be properly overlapped as it won't stick to the Teflon.
