| Valve resource sites | |
| Duncan's Amp Pages | A large and comprehensive site including audio amp schematics, simulation tools, free downloads and the best valve data base I've found on the web. |
| Valve interest sites | |
| The National Valve Museum | This site has a large collection of valve pictures, each with a short description of the valve shown and also several different indices to assist in locating valves. Highly recommended! |
| JMH's Virtual Valve Museum | A large collection of valves with many unusual types such as microwave devices, CRTs, camera tubes etc. A good search engine is provided. |
| Jonz Valve Page | Great site with lots of old radios/TVs, test equipment, information and a very cool 405 line TV testcard generator project with full data. |
| VT52.com | Cool site with projects, data, links and the story of the VT52 triode. Lots on Directly Heated Triodes and not just for your output stage! |
| Ham radio sites | |
| AB0CW's Vintage Communications Gear, Homebrew, and Longwave Page | By Mark, AB0CW. A large site with Ham radio projects, commercial Ham equipment, military and broadcast gear. |
| HappySurfer's home page | By Brian, AF4K/G3XLQ. An extensive site including radios and components for sale. |
| Glowbugs web pages | By Ken, W7EKB. A good collection of glowbug circuits. |
| Simple Radio Transmitters and Receivers | By Ken, W7EKB. Shows a number of simple, but powerful, transmitters. |
| QRP, Hand Made Amateur Radio site | By Kaz, JF1OZL. An excellent, large site with many low voltage valve circuits. |
| Harry's Homebrew Homepage | By Harry, SM0VPO. Large, multi hosted Ham radio website with some nice valve circuits. Other sites Harry maintains have data sheet libraries. |
| WD4NKA Home Page | Various glowbugs, (including the "Regenerodyne") and the home of Tubepad, a schematic drawing package. |