Fldigi is a computer program intended for Amateur Radio Digital Modes operation using a PC (Personal Computer). Fldigi operates (as does most similar software) in conjunction with a conventional HF SSB radio transceiver, and uses the PC sound card as the main means of input from the radio, and output to the radio. These are audiofrequency signals. The software also controls the radio by means of another connection, typically a serial port.
Fldigi is multi-mode, which means that it is able to operate many popular digital modes without switching programs, so you only have one program to learn. Fldigi includes all the popular modes, such as DominoEX, MFSK16, PSK31, and RTTY.
www.w1hkj.com

The needs of our Served Agencies have changed. They still need voice communications but... There's an increasing need for data communications. We need to be able to provide more than just voice communications from a ham with an HT.

Digital voice modulation uses less bandwidth than older analog voice modes such as amplitude modulation, and frequency modulation. The quality of the data received is usually better than an analog signal at the same signal strength. Digital modulation is easier to route and distribute.

D-STAR compatible radios are available for VHF, UHF, and 1.2 GHz amateur radio bands. In addition to the over-the-air protocol, D-STAR also support network connectivity, enabling D-STAR radios to be connected to the Internet to stream voice and data communications.

FLDigi Applications

Getting Started

Fldigi uses your computer's sound card to generate and decode digital signals. Flmsg talks to Fldigi to send and receive messages. All work is done by your computer, don't need an external Terminal Node Controller (TNC). Audio from your computer speakers go into your radio's mike input for transmission. Audio from your radio goes into your computer's mike or line-in for decoding. Don't need an extremely powerful new computer, older machines work just fine

Many ways to interface with computer. Rigblaster SignaLink USB for newer HF radios. But, if necessary, hold radio mike up to computer speaker and... Hold radio speaker up to computer mike! In an emergency, don't really need hardwired interface. Disable all DSP “enhancement” programs on mic.

SignaLink Configuration
SignaLink is very easy to configure. Just connect to computer via USB. Configure Fldigi to use SignaLink USB sound card. Generate just enough audio from computer to trigger SignaLink vox. Use volume controls on SignaLink and don't touch computer audio settings