Around the world in the 90’s Amateur Radio Operators began using a communication method that utilizes the Internet. Echo Link is software which allows Amateur Radio stations to communicate with one another over the Internet, using voice-over-IP (VoIP) technology. The program enables worldwide connections to be made between stations, from computer to station, or from computer to computer. If you are expecting to set up Echo Link in "sysop" mode, you will need a special interface device which connects your radio equipment to your computer. This device allows the computer to control the PTT function of your transceiver.
For use in Sysop mode, your transceiver connects to a hardware interface, which in turn connects to your computer's sound card and serial port. Audio from the receiver goes to the interface board or your sound card's line-in jack, and audio from the sound card's speaker out (or line out) goes through a gain control to your transmitter's microphone input. If your rig has a line-in connection, sometimes available on a back-panel accessory jack, you can usually connect the sound card output directly to line-in.
Features & specification
q 100% galvanic isolation Separation using audio transformers.
q Tone (Bass & Treble) & AGC Controls.
q Adjustable receiver and transmitter audio levels.
q COR (Positive or Negative logic selectable).
q No relays Uses Electronic Switches.
q RS232 signals DB9 Connectors, PSK31 digital modes.
q Header Jumper for portables Handy.
q All audio and control I/O brought out to 3.5mm Stereo jacks for easy interface.
q 13.7cm x 8.7cm, Single Side Board (LRR-300)/Double Side PTH Board (LRR-301).
q Available as a DIY kit or fully assembled high quality components for reliable operation.