ALGO 1825 Powerful Low Frequency Duet Plus Auxiliary Ringer & Paging Amplifier
The Algo 1825 Duet Plus is a high performance low-frequency loud ringer compatible with most business telephone systems in office and industrial applications. The unit is compatible with dry contact closure, analog telephones, and Nortel digital telephones including Norstar, Business Communication Manager (BCM), Meridian 1, and Communication Server 1000 (CS 1000).
Loud ringing can be activated by a relay or switch closure (dry contacts), low voltage detection, 90V analog telephone ringing, or any Nortel TDM digital business telephone.