BUZZER No. 33A


This is an electronic buzzer used in Switchboards 2/-, 3/- and 4/-, which was also used for general purposes.

The circuit also changed over the years - see pictures below.

Mounted by means of a Clip No. 91C (Drawing - 92372).

There is a Mark 1 and Mark 2.  The Mark 2 was introduced in 1973, but it is not obvious what the change was.  The printed circuit board layout changed on numerous occasions.

Adjustable for 24-50 volts DC.

Introduced 1965.

Drawing - 92305.

Diagram - N649.

Specification - S925.

 

 

 

 

 

 
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Last revised: September 28, 2024

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