This isn’t quite a “Don’t Do This” article but it’s close. I recently had someone ask me if it was possible to clean the oxidation off an antenna with cola. First of all it isn’t, although I only let it sit for about a day. So there’s that.
It’s actually not far-fetched though. You can use a cola drink to clean corrosion off a car battery terminal, I’ve done it myself. The key to it is the phosphoric acid that is in cola. It balances out the alkaline corrosion on battery terminals fairly well. It will also put the shine back on a green penny, for the same reason. However, that’s copper oxide, and the black stuff on your antenna is aluminum oxide. Completely different thing.
More importantly, aluminum oxide, while it does take that nice shine off your antenna, isn’t really bad for the antenna. It doesn’t make much difference to the antenna’s ability to receive signals, and a thin layer of aluminum oxide actually prevents corrosion of the antenna by preventing more aluminum oxide from forming. That big difference is one of the reasons that aluminum is used in building materials, cars, and other things instead of iron. When iron starts to oxidize, it just keeps oxidizing. As they say, rust never sleeps. However a little aluminum oxide actually prevents more oxidation, so it’s a good thing.
Because I’m committed to getting you the real answers, I actually did climb up on the roof of our test labs and doused the 50-year-old antenna with soda. A day later I hosed it off but didn’t scrub it, because I didn’t want to affect the test. I did douse it pretty well though, and let me tell you, there was no difference between the parts I’d doused and the parts I hadn’t. They were all uniformly greyish-black. Maybe if I’d left that soda up there a month or two, who knows. But even if I had, that would have just left me with a shiny antenna that was going to oxidize all over again.
Just not worth it. Drink the cola, leave the antenna alone.