Speaker unit for 2-wire systems complete with terminal block and audio control with echo-cancelling, sealed-unit loudspeaker, electret microphone and front-mounted loudspeaker volume control. Complete with microprocessor and 8-position dip switch for programming calls to users. On-board electronic lock-release function (3A) plus C, NC, NO contacts for 10A relay. Timed lock-release input and door open indication. Compatible with power supply unit art. 1210. Dimensions: 102x55x38 mm.
