The CTG-1 install doc lists the following: Pin 12 Common. Pin 11 Yelp. Pin 10 Whoop. Pin 9 Ding Dong. Shorting pin 12 to any of those other pins will produce the associated sound.

To answer your question, which is a bit confusing, if you want the CTG-1 to make a sound when the phone is being called, you must use an Industry Standard single line port and a Viking LDB-2 or LDB-3 bridged on the extension's tip and ring and the normally open contact connected to pins 12 and either one of 11, 10 or 9.

Rcaman

Americom, Inc.
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