Software defined radio

This week Gary showed us his progress with software defined radio. Using an AM antenna and appropriate filtering and mixing Gary was able to produce a signal which he could sample on his soundcard. The signal so sampled could then be simply demodulated through low passfiltering or envelope detection to yield the audio signal (a radio program) which you can easily hear at the end of the video. I thought this was a neat example of an increasingly important form of radio.
Tomas