Cleaning OLD Antenna Wire:
You can clean copper wire for soldering with a mixture of vinegar and salt.
After a few minutes in the solution, even multi-stranded wire, will be clean and shiny, and it will take solder like new wire. I tried this and it works amazingly quickly – seconds rather than minutes. One might try using plain unadulterated white vinegar. Vinegars that have been “contaminated” with flavorful herbs may change the color of the cleaned wire as well as leaving a film that harms the solderability and may very well cause conduction trouble later.
>What is recommended cleaner for antenna surfaces. Is it ok to clean >Aluminum tubes and other contacts with, let us say, #80 scotch brite pad?
Remove the oxidation with a mild abrasive like the scotch brite pad. Aluminum oxide is not a good conductor.
The best anti-oxidation treatment is Gardner Bender Ox-Gard Anti-oxidant Compound available at Home Depot for about $5. The ones from Canadian Tire may be a dielectric grease which sounds good but a dielectric is an insulator. Those greases are meant for spreading over a clamped down battery terminal to keep water out of the connection. Ox-Gard is a conductive.