W6FFC discusses stability considerations and other factors.
http://www.rtty.com/development/Auxiliaries/XT-4/
Mark Dittmar's site with homebrew information and other articles.
http://www.qsl.net/ab0cw/
How to remove the so called "ground loop" and the reentry in the RTTY broadcast.
http://www.ik3qar.it/rtty/1/
Solid state replacements for vibrators used in old military radio power supplies. Universal inverter power supply by Dennis Starks.
http://www.qsl.net/wb4tur/images/dcdc.htm
Jim Garland W8ZR's "homebrew gallery"
http://www.miami.muohio.edu/president/personal/w8zr/homebrew/
Several projects including a complete 80 meter DSB rig.
http://home4.swipnet.se/~w-41522/
Homebrew transceivers and other projects.
http://lea.hamradio.si/~s57nan/ham_radio/
Mostly microwave projects.
http://www.ham-radio.com/wa6cgr/