Videx 835M speech modules 0 buttons

Audio Door Entry Deal

Features:

• The speaker unit circuitry includes:
• The voltage rectifier and stabilizer circuits;
• The modulated tone generator;
• The transmitting amplifier with condenser microphone and volume control;
• The receiving amplifier and volume control;
• The audio balance circuit with the relevant “BALANCE” control;
• The voltage reader circuit: depending on the voltage changes caused by picking/hung up the handset the circuit enable or disable  speech line and door open;
• The enslavement relay to enable the electric lock (one contact normally open which closes to ground on door open signal);
• 2 LEDs to illuminate the name plate (except the 835M-0 model).