AMPLIFIER & LOUDSPEAKER No. 1
Stand alone amplifier with loudspeaker for listening only.

Contains one valve and a special switch that operates two keys.

It also had two pilot lights which were dimmed when the unit was ready and full brightness when in use.

It would appear that if the valve heater element went faulty the pilot lights would not work.

The amplifier could be connected to telephones or cordless switchboards.

Input power requirement is 200v - 250v DC.

Diagrams dated circa 1939.

Wiring Diagram - SA4005.

Connection diagram - SA4083.
 
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Last revised: April 03, 2023

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