The A2D of soundcards is pretty usefuyif you can get your signals into the audible range. The ZetaSDR (second schematic at http://www.qrz.lt/ly1gp/SDR/ http://w

The A2D of soundcards is pretty usefuyif you can get your signals into the audible range. The ZetaSDR (second schematic at http://www.qrz.lt/ly1gp/SDR/ http://www.qrz.lt/ly1gp/SDR/ ) is probably the most rewarding project for the effort I put in. It plugs into a soundcard and I was able (with the help of an antenna tuner) pick up signals from around the world, including some incredibly weak ones. This weekend the VLF station in Sweden https://en.m.wikipedia.org/wiki/Grimeton_Radio_Station https://en.m.wikipedia.org/wiki/Grimeton_Radio_Station will be broadcasting and all you need (in theory) is a very long wire plugged into your soundcard to receive it. Like https://sites.google.com/site/swljo30tb/ https://sites.google.com/site/swljo30tb/