When someone rings the door bell and your phone beeps one of the line buttons should light up , push that button and you should be able to talk back and forth, depending on what kind of door bell you have the user might have to press a talk button to talk back to you. To hook up a answer machine you must tie it into a line on your system ,not to a system jack you will have to add another jack directly to the line you want answered. Hope this helps
dtmf

Russ runs a local service and private tech center.

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