ClassCo VoiceAnnounce Caller ID 500 - Manual (Page 7)

Installation
Set up the VoiceAnnounce 500 by installing three (3) “AAA”
batteries inside the battery compartment on the underside of the
unit. The unit will also work with a compatible AC Adapter
(6VDC output with negative pin polarity.)
Plug one end of the telephone cord into the telephone jack on the
wall, and the other end into either of the telephone jacks on the
back of the unit.
An extra telephone jack is provided on the back of the unit for
connecting a telephone or other device at your option.
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