The Exchange

The Exchange working will not be covered by this site and one should go to numerous other sites for information on such matters.

Main exchanges in the UK started life as manual switchboards, then to electromechanical systems, then crossbar/electronic, followed by System X (electronic) and as this is written in 2021 the UK is converting to IP connectivity.

However, here are some pictures that may be of interest.

Battery room in a 1950's exchange.  Note the busbars feeding the exchange.
The batteries main function was to reduce noise (hum) in the power system.

Racks of Subscribers meters.  These is how the GPO used to bill subscribers.
Today, modern exchanges do the billing via software driven processers.
The lady here has a camera which is connected to a tube which has a flash light in it.  This must be a staged picture
as the camera unit is not lined up with the marks on the meter rack!


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Last revised: September 10, 2021