Utilities macOS
fldigi
Encode and decode amateur-radio digital modes on a Mac with fldigi, a free sound-card modem with a waterfall display, contact logging and message macros.
- Operating system
- macOS; minimum version not specified in the publisher package note
- Architecture
- Universal; publisher expects Intel, M1 and M2 support
- Download package
- DMG disk image
Publisher says built on M2 / Sonoma 14.6.1 and signed but not certified by Apple. Compatibility was not locally tested.
Link checked · Download guidance
What is fldigi?
fldigi turns computer audio into a digital-mode modem for amateur-radio communication. It supports modes including PSK31, RTTY and CW, with receive and transmit text areas, a waterfall for locating signals, a logbook for contacts and macros for repeated messages. It suits operators who want several digital modes in one application rather than a separate tool for each mode.
For on-air operation, configure the audio connection to your radio, input and output levels, and any transceiver-control interface. These settings matter: the manual warns that excessive sound-card input can produce ghost signals and stop correct decoding. Some controls, including QSY, need a configured transceiver-control method.
This entry links to the publisher’s 4.2.13 Mac disk image. The publisher describes its DMG as a universal build expected to run on Intel, M1 and M2 Macs, but does not give a minimum macOS version in the package note. It also says the disk images are signed but not certified by Apple. The screenshot comes from the publisher’s older manual and illustrates the interface; it is not a capture of this release.
What it offers
- Encode and decode digital modes including PSK31, RTTY and CW.
- Locate signals using waterfall, spectrum and oscilloscope-style displays.
- Keep radio contacts in the logbook and use macros for repeated messages.
- Configure sound-card audio, modem settings and transceiver control for your station.
Good to know
- On-air use requires a configured radio/audio connection and suitable RX/TX levels; overloaded audio can prevent correct decoding.
- QSY and other radio-dependent controls need an enabled transceiver-control method.
- Publisher disk images are signed but not certified by Apple; minimum macOS compatibility for this package is not established by the retrieved package note.
Product images
Sources
References used for this listing. Retrieval dates do not indicate hands-on testing.
- fldigi for Mac - Download ↗Retrieved
- W1HKJ Software ↗Retrieved
- Index of /files/fldigi ↗Retrieved
- Publisher Apple disk-image notes ↗Retrieved
- Fldigi Users Manual 4.2.00 ↗Retrieved
- Fldigi Users Manual: Initial Configuration ↗Retrieved
- Fldigi Users Manual: Operating Controls and Displays ↗Retrieved
- Fldigi Users Manual: License(s) ↗Retrieved
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