TXK (Telephone eXchange Crossbar) was a range of Crossbar exchanges used by the British Post Office telephone network, subsequently BT, between 1964 and 1994. TXC was used as the designation at first, but this was later changed as TXC sounded too much like TXE the code used for later electronic exchanges. Prior to this the GPO had standardised on Strowger for automatic switching and had resisted the adoption of Crossbar, preferring to wait for its electronic switching research to bear fruit. The development of electronic systems however took longer than anticipated and the British equipment manufacturers, particularly Automatic Telephone & Electric (ATE), which later became part of the Plessey group feared that continuing to focus the bulk of their production on Strowger equipment would ha