TM 55-1930-209-14&P-1 Table 5-5.  Telephone System Major Components Component /Quantity Location Function Telephone power amplifier/1 Mounted in station Amplifies calls from selector box on aft handset station so they can be bulkhead in dayroom heard at the headset stations Telephone speaker/1 Located above operator's For converting signals from desk in dayroom headset stations into sound Telephone power Mounted in station Acts as regulator between control module/1 selector box on power source and power aft bulkhead in amplifier dayroom Telephone station selector box/1 Mounted on aft bulkhead For selecting telephone in dayroom station (12 stations) to alert crew personnel by activating buzzer or strobe light, for controlling telephone power amplifier volume and for turning on/off 24 Vdc to telephone system Telephone headset/15 Stored in the ROWPU Allows crew personnel to space aft storage area receive incoming calls from system operator and transmit - messages (talk-back) when connected to associated headset station jack receptacle Telephone station Mounted throughout Alerts crew personnel at buzzer/14 barge near headset headset station that they stations are being paged Telephone station Mounted on overhead in Alerts crew personnel strobe light/3 center of ROWPU space at headset station that they and in void 4 port and are being paged starboard Telephone indoor headset Mounted in dayroom, Allows crew personnel to station/14 workshop, ROWPU plug in telephone headset space and each void and communicate with dayroom system operator or another headset station Telephone outdoor Mounted on weatherdeck Allows crew personnel to plug headset station/7 in 5 stowage boxes in telephone headset and and on top of deckhouse communicate with dayroom in two watertight boxes system operator or another headset station Operator telephone Mounted on operator's Allows messages to be sent to handset station/1 desk in dayroom and received from crew telephone stations 5-26