Cold War Sites

GPO PR1 Protected Repeater Station

 Created 21-10-2001   Last update 28-10-2012

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If you can improve on the narrative that accompanies the following photos then please email me.

Motor generator set

008 -  A 'Continuity Set'. A DC motor is powered by the exchange batteries and drives an AC generator which maintains an uninterrupted mains voltage supply to transmission equipment during a failure of the grid. Meanwhile the engines start up and take over. If there are problems starting the main engines then this will give some leeway while they are sorted out.

Small Compressor

004 - A small electrically driven compressor which supplied air to the tanks in the top right corner. This compressed air would have been used as a means to start the diesel engines.

Fuel Valves

005 - Fuel control valves. The station had enough fuel to last for four weeks.


003 - Batteries to supply an uninterruptable power supply (UPS) to essential equipment and lighting in the event of power failure. This photo shows a much reduced battery supplying what was left working in the station. Originally there were battery rooms with very large open lead acid cells for standby operation.

Mecury Arc Recifier

012 - A mercury lamp rectifier used to produce a clean DC current from an AC input. The sides of the cabinet would have had grills fitted in them and an bright white light would be seen when the device was running. It was used to charge the batteries.

 Switchgear doors

042 - Door leading the the high voltage (HV) switch room. The sigh warns of 11,000 volts (11kV).

 HV Switchgear

006 - High voltage switchgear.


034 - A closer view of the switchgear.


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