Telephone switching circuit data delay equalisation - has incoming shift register and store clocked from transmit terminal over separate transmission lines

摘要

The transmission of data between two points in a telecommunications network uses digital switches. It is particularly applicable to PABX interconnection with the main network and is designed to overcome errors introduced by various transmission delays. Two transmission localities (UL) are provided between the two switching units (M1,M2). Transmission of data between the two points (M1,M2) is in serial form. In the second unit (M2) an equalising circuit (AGL) receives the clock pulse from the first (M1) on a dedicated facility (ST). Channel clock information from the first unit (M1) is also sent over a second facility (KT). These two clocking rates are used in the control of the receive modules (M2) incoming shft register (ESR) and subsequent intermediate store (E25).