FlexRadio Systems - Software Defined Radios
- FlexRadio Systems delivers the first truly open source Software Defined Radio transceiver for Amateur Radio use. Receive Only versions are also available for non Amateur Radio applications. Read the SDR Articles and the SDR-1000 Product Information.
A low power 3.5MHz ARDF transmitter
- This low power transmitter is developed for ARDF exercising purposes but of course can be used as super QRP transmitter either. With 1 or 2 meter wire as antenna and a ARDF receiver with ferrite-rod antenna the range is about 100m but with better antennas and a 'real' receiver the range is probably much larger.
Bowden's Hobby Circuits
- A small collection of electronic circuits for the hobbyist or student. Site includes over 100 circuit diagrams, links to related sites, commercial kits and projects, newsgroups and educational areas. Most of the circuits can be built with common components available from Radio Shack or salvaged from scrap electronic equipment