SPEAKING CLOCKS


Speaking Clocks were first installed in the UK in 1936 at Holborn, London with a second pair installed in Liverpool in 1942.  The clocks consisted of two units on each site, one being a standby, but both Holborn and Liverpool were wired together, via the GPO trunk network, so that if there was a complete failure at one of the sites, the other site would serve the whole country.

Holborn was also connected to the Greenwich time wires in Faraday Building.

The output from the clocks were fed to the local Repeater Station for distribution around the country.

Speech was recorded onto an optical disc which was read by photo cells.

Amplifier and Control equipment
 
             
Pendulum Unit
 
Even Minutes Disc and Optical Unit
 
Hours and Minutes Cam Shaft

Click here for more Speaking Clock information

 

 
 
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Last revised: December 31, 2021

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