Intercom in the workshop, training room

The communication system can be used, for example, between a teacher-operator and a student during class.

It is based on two dedicated RDL ST-IC1 intercom amplifiers.

► the student's voice, picked up by a condenser microphone mounted under the ceiling (BM-112 or BM-113), is transmitted through a loudspeaker in the operator's room
► the operator can transmit a message to the student by pressing a button (the diagram shows a footswitch, but a button on the TSG-550 microphone unit is easier)

The signal in the loudspeakers is muted by the amplifiers according to the state of the button to avoid acoustic feedback. Both amplifiers can be powered from a single 24V DC power supply (the power line is not shown in the diagram).