http://www.aaroncake.net/circuits/index.asp
http://www.somerset.net/arm/fm_only_one_transistor_radio.html
http://www.njqrp.org/regen/
http://www.njqrp.org/tuna/tuna.html
http://www.microengineeringlabs.com/index.htm
http://www.boondog.com/%5Ctutorials%5Cpic16F84%5Cpic16f84.html