The square grey plastic box, item 375507, used to provide external bells on Norstar and some other systems.
I used to have, or could find online, information about the terminals, but I've lost it. Can anyone help?
Inputs PL1
AC IN
DC AUX
DC +
DC -
AC COM
(there are 4 connections for 5 designations - are DC- and AC COM the same?)
Output PL2
HIGH
N/C
LOW
Link to photo of the outside:
http://www.telephonesuk.co.uk/images...gen_2a_out.jpg