I may have told thos story before but:
Worked for an electronics company selling wholesale to a number of different people, one such person made caravan antennas those bloody awful bits of white plastic tube with a T piece at the top and a piece of wire attached to a balun extending down the arms of the T.
This bloke designed a better antenna that used two pieces of flat aluminium and was therefore able to get more signal than a piece of wire (his words not mine), bear in mind this bloke worked as a machinist at his day job.
One day I was dropping off 100 baluns as he sold shitloads of these things to caravan dealers, he was talking about signal being better at night and I tried to explain that UV affected RF and that was why AM radios worked better at night, he asked if there was a way to overcome the problem and I said use black plastic tube.
Never thought much more about it until I saw his ‘improved’ antennas pop up that were black.
What’s worse is the bastard probably made a killing.