835M speech module.
FOR “1+1” SYSTEMS
Videx 835M speech modules are for the older 800 series panels. Only very limited stock.
The speaker unit circuitry includes:
a. The voltage rectifier and stabilizer circuits;
b. The modulated tone generator;
c. The transmitting amplifier with condenser microphone and volume control;
d. The receiving amplifier and volume control;
e. The audio balance circuit with the relevant “BALANCE” control;
f. 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;
g. The enslavement relay to enable the electric lock (one contact normally open which closes to ground on door open signal);
h. 2 LEDs to illuminate the name plate (except the 835M-0 model).
The version 835M-0 has not the terminals “P1”, “P2”, and “C1”.
On the 835M-1, terminal “P2” is not fitted