This amateur radio project by Yaesu utilizing the C4FM protocol. The 12.5 kHz channel spacing in using the C4FM digital modulation mode allows high-speed data communication with reliable voice communication and strong error correction performance. C4FM offers a 9.6 kbps data transfer rate speed. It can transmit data and voice information at the same time.
Radios and repeaters utilizing this technology are capable of using analog and digital (multi-mode). It is up to the repeater system admin to choose the operating mode to set the repeater in, which may allow digital and/or analog on the input and to allow analog and/or digital on the output. Automatic Mode Select function identifies and selects one of four modes automatically upon receipt of the respective signal.
Yaesu System Fusion repeaters can also connect to WIRES-X nodes while operating in the digital C4FM format.