Bogen TPU250 250-Watt Telephone Paging Amplifier (Refurbished)Specifically Designed for telephone paging, the Bogen TPU series of telephone amplifiers offers a choice of rated power output from 15 to 250 watts. Input terminals are provided for a 600 Ohm balanced telephone line and background music source (FMR or TP30D), as well as a balanced low impedance microphone in the TPU 100, TPU 60 and the TPU 35. The built in night ringer (except TPU 15A) sounds a tone through the paging system speakers when triggered by