A data-burst type synchronous duplex ARQ system using the ITA 2 alphabet. 5 characters are sent, made up of 5 bits per character, followed by 7 parity check bits. Total of 32 bits sent per data frame. A complete cycle has a duration of 704 msec and consists of 256 msec transmit, 96 msec pause, 256 msec receive, 96 msec pause.

System will hop about in 400Hz steps to clear interference. If 3kHz SSB channel is full of interference, it will hop to another frequency altogether.

Click here for a typical ARTRC sound