OK, I know less than zilch about ham radio, but I think these cards are/were a way for people to trade frequencies (?) so they can chat?
Anyhow, they're all from the other side of the world, they all have cartoons on them, and they're a heck of a lot of fun to peruse.
Technorati Tags: andertoons, cards, cartoon, cartoonist, cartoons, comics, flickr
They are actually confirmations of a discussion that happened, so you can show your friends a piece of paper when they say "no way you talked to outer slobovia on 3 watts of power".
These are great.