PRESS BUTTON UNIT No. 4
This a press button unit that consists of a 12 button keypad marked 1 to 0, # and *.  The push-buttons are arranged in 3 columns of 4.

The keypad will work with MF (DTMF) systems only.

Variants:-
PBU No. 4A is fitted in Telephones SA4258 and 2/SA4258.
PBU No. 4B is fitted in Telephones 4/SA4258.
PBU No. 4C is fitted in Loudspeaking Telephone SA4265.

 
 
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Last revised: September 27, 2024

FM