I don’t know if the guy who created this is a ham (he does say he’s an engineer), but it’s a neat application of some old-school technology. He uses a PIC 12F510 to output a Hellschreiber modulated square wave right to his PC’s sound card line in port. I really get a kick out of seeing one of these “obscure” ham technologies escaping out into the Maker universe. The hardware is dead simple, as you can see in the instructions. If you wanted to try to create a Hellschreiber beacon, I don’t see why you couldn’t just take this same design and plug it into your rig’s sound card interface instead of a PC. I’m already thinking about how cool this would be to try…there’s a good chance I will give it a shot (with an AVR) after I finish up my latest DC transceiver. Watch out for more aliens infecting the bands.
Kind a cool. I saw his AM modulated* clock on the scope and now this which is FM. I was trying to tell what frequencies he was using. I must have missed that. I think pretty narrow, maybe 10s of Hz?
I was trying to figure what the bandwidth would be?
Who would have ever thought that the sound cards on PCs would be so useful. Aliens, no, somebody needs to send a face. Kind of like what we would hope SETI would receive.
*I know AM modulated is a double whatever, but it sounded better.
72, Chris