Run frequency measurement tests and calibrate a sound card to a signal. Use serial port connections to control the radio, select between different digital modes, work with CW, PSK, MFSK, RTTY, FM, AMS, LSB, Hell, DominoEX, Olivia, and Throb types, and log data.
Download of Fldigi 4.2.4 was on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. Fldigi.exe is the default file name to indicate the Fldigi installer. This free software was originally designed by David Freese.
The following versions: 4.1, 4.0 and 3.2 are the most frequently downloaded ones by the program users. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. Fldigi was developed to work on Windows XP, Windows XP Professional, Windows Vista, Windows 7, Windows 8, Windows 10 or Windows 11 and is compatible with 32-bit systems. The program is included in System Utilities.
From the developer:
Fldigi is a modem program for most of the digital modes used by radio amateurs today: CW, PSK, MFSK, RTTY, Hell, DominoEX, Olivia, and Throb are all supported. It can help calibrate a sound card to a time signal and do frequency measurement tests.
You may want to check out more software, such as Fldigi-DXLabs Gateway, FldigiDXCluster or flrig, which might be similar to Fldigi.
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