PRESS BUTTON UNIT No. 3
This a press button unit that consists of a 12 button keypad marked 1 to 0, # and *.

The keypad will work with DC Code C signalling systems only.

Variants:-
PBU No. 3A used in Telephones SA4252, 1/SA4252 and 2/SA4252.
PBU No. 3B used in Telephones 3/SA4252.
PBU No. 3C used in Loudspeaking Telephone SA4255.
PBU No. 3D used in Press Button Units 1/SA4259 and 2/SA4259.

Drawing - 93090.

Specification - S1121.

 
 
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Last revised: September 27, 2024

FM