1200 BITS PER SECOND DUPLEX MODEM STANDARDIZED FOR USE IN THE GENERAL SWITCHED TELEPHONE NETWORKAND ON POINT-TO-POINT 2-WIRELEASED TELEPHONE-TYPE CIRCUITS
Introduction This modem is intended for use on connections on General Switched Telephone Networks (GSTNs)@ and on point-to-point circuits when suitably conditioned. The principal characteristics of this modem are as follows: a) duplex operation on 2-wire GSTN and point-to-point leased circuits@ b) channel separation by frequency division@ c) differential phase shift modulation for each channel with synchronous line transmission at 600 bauds (nominal)@ d) inclusion of a scrambler@ e) inclusion of test facilities.