Improvements made to a boatanchor classic.
http://www.amwindow.org/tech/htm/eico730.htm
Files of mods arranged by brand and model, plus a few Heath.
http://qrz.com/download/main/mods.html
Digitizing information from the age of radio. Preserving books, magazines, manuals, schematic diagrams and other paper information.
http://www.radioera.com/default.htm
UTC Transformer data online.
http://amwindow.org/tech/htm/modtran/utc/utc.htm
Soup up your Johnson.
http://amwindow.org/tech/htm/viking2.htm
Manuals listings.
http://www.fairradio.com/manual.htm
Test equipment manuals - searchable database of over 30,000 manuals.
http://www.usimperio.com/consolidated/index.htm
W8TOW describes in detail how to improve the audio on the Johnson Viking Valiant transmitter.
http://www.msu.edu/~wb9tow/mods.htm