No. 1 ESS ADF: Teletypewriter stations and transmission facilities

A solid-state electronic station controller, small enough to be housed within Model 33, 35 and 37 teletypewriters, administers station on-line procedures. To realize automatic message reception and transmission at the station, the controller samples all traffic exchanged between the line and the station teletypewriter, detects message-and device-control characters and generates and detects station-identity codes. In addition, the controller monitors the status of the station teletypewriter and provides appropriate alarms which are displayed on an attendant unit. Stations are linked to the No. 1 ESS ADF office via the Bell System's private line telegraph network. New ac and dc data sets have been developed to accommodate speeds up to 300 bauds with lower distortion and crosstalk generation than previously attainable with former transmission apparatus.