Amateur
- 201
- Southern Ontario Packet Radio Association (SOPRA)
- Official site. Features details on the packet nodes and services provided by the organization to the amateur radio community, with frequencies.
- 202
- Tucson Amateur Packet Radio (TAPR)
- TAPR is an international non-profit educational research and development organization focused on the issues of amateur radio wireless digital communications.
- 203
- UI-View32 Windows APRS Client
- Complete information on open-architecture, intelligent digi-peater and IGate. Works with TNCs in terminal mode, KISS mode, AGWPE and BPQ. Many map options.
- 205
- Ham Radio Circuits
- Circuit diagrams of Ham Radio equipment, including 7 MHz SSB Transceiver, AM, FM, DSB transmitters, FSM, Dummy load, Antenna, and filters.
- 206
- Pixie- HF Transceiver Kits
- High frequency radio transceiver project for QRP enthusiasts. Features plans and workshop.
- 209
- QRP SSB/CW Transceiver/QRP Radio Kits
- Covers the most common QRP transceiver kits. Includes images, relevant information, links and reviews.
- 210
- Homing In
- All about hidden transmitter hunting and radio direction finding for radio amateurs. Includes news, results, history and FAQ.
- 212
- N6QAB Radio Direction Finding
- Pictures and descriptions of radio direction finding and related equipment.
- 214
- Radio Direction Finding Projects
- A collection of useful and interesting projects for the RDF enthusiast by Joe Leggio, WB2HOL.
- 216
- Human Space Flight (HSF) Realtime Data
- NASA information including television, orbital and satellite tracking and weather.
- 217
- KK5UFO
- Jeff in Colorado includes a satellite frequency list and blueprints for high gain antennas.