Fldigi

Fldigi is based on the lightweight portable graphics library FLTK and the C/C++ language. Because of this, the software can run on many different operating systems such as:

• Microsoft Windows (2000 or newer)
• macOS
• Linux,[12]
• FreeBSD,[13]
• OpenBSD,[14]
• NetBSD,[15]
• Solaris.[16]

Additionally, Fldigi is designed to compile and run on any POSIX compliant operating system that uses an X11 compatible window system / graphical user interface.[16]

The Fldigi software is written in highly portable C/C++ and can be used on many CPU architectures, including:

• amd64
• i386
• armhf/armel
• ia64
• mips
• mipsel
• powerpc
• s390
• s390x
• sparc
• Raspberry Pi.[17]

Multiple sound systems are supported by Fldigi, allowing the program to abstract the sound card hardware across differing hardware and operating systems.

• Open Sound System (OSS)
• PortAudio
• PulseAudio
• Read / write to WAV files (file I/O)

Flamp implements the Amateur Multicast Protocol by Dave Freese, W1HKJ[22] and is a tool for connectionless transferring of files to multiple users simultaneously without requiring any existing infrastructure. The program breaks a given file into multiple smaller pieces, checksums each piece, then transmits each piece one or more times. When all parts are correctly received the sent file is re-assembled and can be saved by receiving stations.[23] This program is useful for multicasting files over lossy connections such as those found on High frequency (HF) or during emergency communications.

Flarq implements the ARQ specification developed by Paul Schmidt, K9PS[24] to transfer emails, text files, images, and binary files over radio. This protocol is unicast and connection-based. The software seamlessly integrates with existing email clients such as Microsoft Outlook, Mozilla Thunderbird, and Sylpheed.[25]

Flmsg allows users to send, receive, edit, and create pre-formatted forms. Such a system speeds the flow of information during emergency communications. The software has a number of forms built-in including FEMA ICS forms, MARS reports & messages, Hospital ICS forms, Red Cross messages, IARU and NTS messages.[26]

Flwrap is a tool for the sending of files using a simplified drag and drop interface. Data compression is available also, which reduces data transfer times.[27]

FLNet assists net control operators in keeping track of multiple stations during digital amateur radio nets.

FLLog is a logging software which keeps track of conversations between amateur radio operators in a database format known as ADIF.

FLWkey is a simple interface to control an external piece of hardware called a Winkeyer. This is a Morse code keyer which is adjustable via computer commands over USB.

This is a telnet client to remote DX cluster servers, which is a real-time reporting of stations heard transmitting, and their frequencies. It does not connect to Fldigi.

Flaa is a control program for use with the RigExpert AA-xxxx series of antenna analyzers, and does not connect to Fldigi.

FLRig is a component of the FLDigi suite of applications that enables computer aided control of various radios using a serial or USB connection.

Using FLRig in combination with FLDigi, events such as frequency, power level, receiver gain and audio gain may be adjusted from the computer automatically or by user intervention.

The software is also utilized by some organizations for both routine and disaster/emergency relief services.

• Multiple state and county emergency operations centers[33][34]
• W1AW (ARRL)[35]
• Amateur Radio Emergency Service (ARES)[36][33]
• Radio Amateur Civil Emergency Service (RACES)[37]
• Civil Air Patrol (CAP)[38]
• SATERN, the Salvation Army Team Emergency Radio Network[39]
• SKYWARN a program of the United States' National Weather Service (NWS) whose mission is to collect reports of localized severe weather.[40]

Following the successful tests by the Voice of America's VOA Radiogram program, international and government shortwave broadcasters began testing and experimenting with digital data over shortwave broadcast channels using the Fldigi software.[41] These tests led to regular weekly digital broadcasts by the broadcasters listed below.

• VOA Radiogram, service terminated in 2017 and continuing as Shortwave Radiogram.
• In June 2017, following the demise of VOA Radiogram, Shortwave Radiogram began broadcasting digital data-streams using Fldigi via WRMI in Miami and Space Line Spaceline Bulgaria - Broadcasting Airtime on shortwave, satellite and internet in Bulgaria.[42]
• Radio Havana Cuba
• Radio Moscow
• Radio Australia[43]
• Radio Miami International
• Italian Broadcasting Corporation[44]
• WBCQ (SW)[45]
• Mighty KBC[46]

The Fldigi suite of programs has become popular within the U.S. Army and U.S. Air Force Military Auxiliary Radio System.[47][48]

Fldigi is being used in-testing as part of the Department of Homeland Security Shares program, which utilizes "existing HF radio resources of government, critical infrastructure, and disaster response organizations to coordinate and transmit emergency messages"[49][50]

Fldigi is used as the underlying modem for the PSKmail project.[51] PSK Mail allows users to retrieve and send normal emails over radio.

In 2014, the group Anonymous released a communications tool named AirChat, which used Fldigi as the underlying modem. This provided a low speed yet reliable data connection using only moderate radio hardware. The AirChat software allows for anonymous transmissions of both encrypted and unencrypted messages over unencrypted channels.[52][53][54]