Joe S. wrote:

John:

THANK YOU!!! Exactly what I needed -- I don't know how you found that -- I
spent an hour searching with Google for various combinations of
anti-oxidant, antioxidant, applying, application, etc., etc.

It took a few tries, including adding the words [aluminum copper
electrical] to reduce the diet pill adds.

I'll pick up a tube/can/jug/whatever of Penetrox tomorrow at my local
electrical supply house, disassemble both antenna mounts and connectors,
"abrade" them thoroughly, and slap the Penetrox onto every metal-to-metal
junction.

For aluminum, (which oxidizes almost instantly in contact with air)
they recommend coating the surface and then doing the final abrading,
so the fresh surface has no contact, at all, with air, before the
joint is assembled. It sounds a little like trying to make a dry
joint under water.