GH205 and GH206 medium-speed data systems

The GH205 (both-way) and GH206 (either-way) data transmission systems employ automatic error detection and correction techniques. They are capable of operating at speeds up to 1200 bauds with a variety of input/output devices. Transmission is in blocks of 256 bits of which 240 represent information content, 12 are for protective redundancy, and 4 are service bits. The cyclic coding uses a protective polynomial to give an average improvement factor of 15000. These systems are compatible with the modern interface recommendations of CCITT and have been operated over a wide variety of national and international circuits including satellite links.