Independent intercom device that allows you to connect the intercom entry panel directly to an analog input of a PBX. Base module equipped with 1 button (expandable up to 64 buttons using the expansion accessory with 4 call buttons code 1148/4), each of which can be associated with 2 numeric destinations of 24 digits (for day / night service or sequential call ), 2 independent and configurable actuator relays, each of which can be associated with up to 6 lock release codes, configurable in 8 different operating modes (e.g. lighting, sequential opening, for additional bell, gradual door opening). Also expandable using the numeric keypad accessory cod. 1148/6, which allows the entry of access codes or public telephone numbers or of the extensions of a PBX. Main functions: self-activation, two two-digit codes to end the conversation, two codes to activate the outputs via telephone by means of 1 pulse and two codes by means of 2 impulses, automatic answer to incoming call with variable number of rings, possibility to configure the time before to hang up if a new selection is made, two codes to deactivate the intercom system from the telephone, self-power supply, tag lighting from external power supply. Loudspeaker and microphone volume adjustment, and the possibility of adapting the electronic volume without having to open the front panel. Easy HW configuration via DIP switch, and software programming from telephone via DTMF tones (also remotely, with telephone call to the Sinthesi S2 module) and from PC via dedicated software and USB interface (1148/9). Access to programming with password.