I just repaired (cleaned and reassembled) an antenna that had a problem with corrosion between the female chassis mount N connector and the aluminium plate it was mounted on. The connector was made of silver plated brass. Is there anything you can treat the connection with that will prevent this problem. I was thinking Alonox but I have no experience using this material and only know of using it with electrical wiring. Any suggestions would be appreciated.

Jimmie

On Thu, 7 Mar 2013 13:19:02 -0800 (PST), JIMMIE
wrote:

I just repaired (cleaned and reassembled) an antenna that had a problem
with corrosion between the female chassis mount N connector and the
aluminium plate it was mounted on. The connector was made of
silver plated brass. Is there anything you can treat the
connection with that will prevent this problem.
I was thinking Alonox but I have no experience using
this material and only know of using it with electrical wiring.
Any suggestions would be appreciated.

The corrosion wasn't between the silver and aluminum. It was between
the copper in the brass, and the aluminum.

The usual fix is to insert a washer made from some material half way
between copper and aluminum in the glavanic series. That's usually
stainless steel.

You may want to read about corrosion from an expert:
http://yarchive.net/electr/galvanic_corrosion.html
So whatever is necessary to exclude moisture from the sandwitch.

Alconox isn't going to do anything except temporarily clean the grease
and crud off the surface of the aluminum. It's really good stuff for
many things, but not for preventing corrosion.
http://www.alconox.com

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

Jeff Liebermann wrote:

Alconox isn't going to do anything except temporarily clean the grease
and crud off the surface of the aluminum. It's really good stuff for
many things, but not for preventing corrosion.

I have in my eBay wish list a tub of conductive grease for antenna
connections.

I've never quite gotten around to buying it. :-)

Does it do any good?

Supposedly you use it like the antioxidant grease for aluminum power
wiring, except this is for antenna connectors. It gets in the threads
and resists water.

Geoff.



--
Geoffrey S. Mendelson, N3OWJ/4X1GM/KBUH7245/KBUW5379
It's Spring here in Jerusalem!!!

On Fri, 8 Mar 2013 10:24:03 +0000 (UTC), "Geoffrey S. Mendelson"
wrote:

Jeff Liebermann wrote:

Alconox isn't going to do anything except temporarily clean the grease
and crud off the surface of the aluminum. It's really good stuff for
many things, but not for preventing corrosion.

I have in my eBay wish list a tub of conductive grease for antenna
connections.

I've never quite gotten around to buying it. :-)

Does it do any good?

Maybe. It depends on the conductivity (ohms/square). If doped with
silver flakes, it will be quite good at producing improving an
electrical connection. If carbon, it will make a nice heater.
However, the real danger is if you remove the normal conduction path,
and you pump a fair amount of current or RF *THROUGH* the grease. No
matter how good the conductivity, it's going to get hot. Hot grease
explosions are not my idea of fun. I've had greasy metal explosions
in a spot welder which should be similar.

The purpose of conductive grease is to prevent rotating electrical
machinery from turning into a static electricity generator. Small
arcs across the bearing will eventually pit the surface and destroy
the bearing. Silver bearing grease is also good for improving the
thermal conductivity for heat sinks. I use it for CPU to heat sink
thermal grease.

Supposedly you use it like the antioxidant grease for aluminum power
wiring, except this is for antenna connectors. It gets in the threads
and resists water.

If water gets into the threads, you're already lost. The threads are
too much of a labyrinth of holes to be sure that a grease only seal is
effective. Grease also does not insure an air tight connection, which
is really what is needed to prevent capillary action and/or internal
partial vacuum, from sucking in the water. In my never humble
opinion, the best waterproofing is wrapping the connectors from end to
end in 1" PTFE plumbing tape. Then apply a layer of Scotch 33
electrical tape over the PTFE layer to hold it in place. I had a
running experiment on my roof for about 10 years using this method. It
works and the connectors look like brand new when the PTFE tape is
removed. It's also VERY easy to do rework.

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

On 3/8/2013 2:24 AM, Geoffrey S. Mendelson wrote:
Jeff Liebermann wrote:

Alconox isn't going to do anything except temporarily clean the grease
and crud off the surface of the aluminum. It's really good stuff for
many things, but not for preventing corrosion.

I have in my eBay wish list a tub of conductive grease for antenna
connections.

I've never quite gotten around to buying it. :-)

Does it do any good?

Supposedly you use it like the antioxidant grease for aluminum power
wiring, except this is for antenna connectors. It gets in the threads
and resists water.

Geoff.



Don't bother. It the world's worst dust collector! Then it's really hard
to get the combination off when you take the joint apart.

Paul, KD7HB

In message , Paul Drahn
writes
On 3/8/2013 2:24 AM, Geoffrey S. Mendelson wrote:
Jeff Liebermann wrote:

Alconox isn't going to do anything except temporarily clean the grease
and crud off the surface of the aluminum. It's really good stuff for
many things, but not for preventing corrosion.

I have in my eBay wish list a tub of conductive grease for antenna
connections.

I've never quite gotten around to buying it. :-)

Does it do any good?

Supposedly you use it like the antioxidant grease for aluminum power
wiring, except this is for antenna connectors. It gets in the threads
and resists water.

Geoff.



Don't bother. It the world's worst dust collector! Then it's really
hard to get the combination off when you take the joint apart.

One of best ways of preventing corrosion of connectors and connections
is to give then a good waft of WD40 before, during and after assembly
(don't go mad, but don't be too mean), wipe off 'not too well' with a
cloth lightly impregnated with some WD40 (ie slightly oily), and tape up
tightly with self-amalgamating tape. The connection will last for ever.
--
Ian