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Just landed on my first C4FM repeater net. It's pretty cool! It shows both the call sign and distance from the repeater of the transmitting stations. :O #AmateurRadio #HamRadio
in reply to Neil E. Hodges

In 2013 Yaesu introduced “System Fusion,” new technology utilizing C4FM 4-level FSK technology for transmitting digital voice data. The System Fusion communication protocol enables devices to analyze an incoming signal and automatically determine if it is using C4FM or conventional FM mode. System Fusion also enables data transfer at full rate with speeds reaching up to 9,600 bits per second.