Check the listing for details. Viking electronics PA-15 15 Watt Paging Amplifier And Loud Ringer. Condition: New. Listed at 219.84 USD. 15W of paging power Drive up to 15 8-ohm speakers 600-ohm output to drive additional amplifiers Select: FXO (loop start), FXS (ring trip), or paging port (VOX relay) interface mode Independent volume controls for Paging, Ringing Tones, and Background Music 36V DC talk battery for interfacing with FXO or unused phone system line input/trunk port Compatible with 24V to 48V FXS (ring trip) analog station operation 800Hz pre-announce page tone (on/off) Provides "Night Bell" warble tone via contact closure or independent ringing analog circuit Choose one of four ringing sounds:- Electronic warble (traditional loud ringer)- Double gong (two identical "gong" tones)- Quadruple chime (four descending chime tones)- Door chime (ding-dong) Night transfer switch input CPC detection for immediate disconnect Busy signal detect disconnect Adjustable silence time out disconnect Programmable VOX trigger sensitivity and time out 16 to 72 second (or off) default disconnect timer