Communications
- 261
- Data Professionals Heathkit Page
- Providing support for legacy Heathkit products. Offers manuals and parts.
- 263
- Donner's Digital Interfaces
- Sells interfaces made for specific Amateur Radios for doing digital modes and rig control.
- 265
- Ham Test Online
- Web-based training for the ham radio written exams. Includes material for both Canadian and U.S. exams.
- 266
- Hamstudy.com
- Self-study courses for Canadian Basic and Advanced amateur radio exams. Full access requires a 30 or 90 day subscriptions.
- 267
- Harlan Technologies
- Home-based supplier of amateur television components and customized name badges and luggage tags. Includes company history. Machesney Park, Illinois.
- 269
- I-Link Boards, Kits and Parts
- WB2REM sells all mode interfaces including VoIP, Echolink and EQSO. Provides parts list and documentation.
- 270
- K2RF
- Manufacturer of Dymanic Speech Limiters and Equalizers, Repeater products, and video encoders.
- 271
- MDM Radio
- Supplier of used radio equipment, including mobiles, repeaters, manuals and books, and parts.
- 272
- Milestone Technologies, Inc.
- Telegraph keys, bugs, paddles related telegraphic equipment, Codemaster V Morse Code training system, books and other publications.
- 273
- Norm's Rotor Service
- Specializing in repairing antenna rotors, and also sells new and rebuilt rotors, control boxes and parts.
- 275
- On Line Ham Radio Class
- Multimedia class for United States students to study for the Technician, General or Extra licenses.
- 276
- OpenTracker Project for APRS
- Home of the OpenTracker, from Argent Data Systems, a device that is connected to an amateur radio and a GPS, allowing GPS data to be transmitted over amateur radio using the APRS protocol. Also supplies products that include SSTV, simplex repeaters and GPS receivers. Santa Maria, California.