A collection of pictures of AK radios, advertisements, brochures, operating manuals, and a profile of the company founder. http://www.atwaterkentradio.com/
Brian McAllister's restoration resources, in the form of high-resolution GIF images of service notes and schematics for many radios, audio amplifiers and preamplifiers, phonos, and tuners. He has a special section for several German radios (Grundig and Te http://oldtech.net/
An article by James D. Keeline about the series of juvenile novels written by several ghostwriters under the pen name of "Allen Chapman" and others in the 1920s. Includes images of original covers. http://www.keeline.com/Chapman/
Features a brief profile of the company formerly located in Sandusky, Ohio. Includes photos of the plant site and a few models from the production line. http://www.firelandsradios.com/Philco/
An archive of over 1000 photos of antique radios, information on future and past club meetings and auctions, and reference material for repairing old sets. http://users3.ev1.net/~wck5/
Austrian radio history, with a profile of Eng. Franz Zehetner (1907-1986) and his radio and television products, with photographs and advertising copy. [Mostly German, but with some English text] http://www.radio-zehetner.at/
Base diagrams, characteristics, and outlines for thousands of vacuum tubes, provided by Bill Beech's Ham Radio Server. http://www.nj7p.org/cgi-bin/tube/