|This Switchboard was used by the BPO to provide
night service on P.A.B.X.s. It has a connection to one exchange line
and one P.A.B.X. extension line.
Incoming calls either from the exchange line or the P.A.B.X. operate the drop flap indicators and can also sound a DC bell.
There is a telephone associated with this Switchboard, which can answer the exchange line, transfer the exchange call to another extension by dialling via the extension line circuit and also connect a calling extension to the exchange line.
Both calling and clearing alarms are given.
Mentioned in the IPOEE booklet called Private Brach Exchange Installation (1932) and the picture below was taken in 1939.
Last revised: January 14, 2019