Flrig is a desktop application for controlling amateur radio transceivers. It can operate independently or alongside other applications from the W1HKJ suite, including Fldigi, giving operators access to frequently used transceiver controls without repeatedly working through the radio’s front panel.
Unlike applications that delegate radio communication to a separate generic library, Flrig contains its own transceiver control implementations. Individual radios are represented by dedicated classes, allowing the program to expose capabilities appropriate to the connected equipment.
This is free and open source software.
Key Features
- Control frequency and operating mode from the desktop.
- Read and change supported radio settings through the transceiver’s CAT interface.
- Display signal, power, SWR and other meter information where the connected radio exposes it.
- Adjust filter bandwidth and related receiver settings on supported equipment.
- Control transmit functions including PTT and radio-specific operating controls.
- Support split-frequency operation for radios that provide the necessary CAT commands.
- Read from and write to transceiver memories where supported.
- Maintain frequency and operating information without requiring a separate Hamlib process.
- Exchange radio-control information with Fldigi.
- Expose control functions through XML-RPC so other applications can communicate with Flrig.
- Provide configuration for serial and USB-connected radio interfaces.
- Support a substantial collection of transceivers from major amateur radio manufacturers.
- Run as a standalone radio-control application when digital-mode functionality is not required.
Website: www.w1hkj.org
Support:
Developer: David Freese
License: GNU General Public License v3.0

Flrig is written in C++. Learn C++ with our recommended free books and free tutorials.
Related Software
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|---|---|
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| Hello Contest | Amateur radio contest logger with CW support |
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Read our verdict in the software roundup.
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