Mystery signal challenge
I'm currently doing some experiments with electronics, and in the process I captured the signal you can find in the attached file. I captured it through my sound card's microphone input
, and I've amplified it in software so it's easier to "appreciate". (Update: I've managed to perform a way better capture, so this is as it comes straight from the sound card, with no extra amplification.) Obviously I know what it is, but I'd like to know who among the people who happen to read this will also be able to identify it — and better yet, tell me what's in the signal.
One clue: this signal is produced by something that was invented in 1969.
Post your guesses and comments in the story on Google+.