Digital Sound activated Switch Circuit Diagram

This is an Electronic Digital Sound activated Switch Circuit Diagram. A sensitive electret microphone picks up the sound and feeds the signal to a two-stage amplifier circuit, consisting of Ula and Ulb. The amplified output of Ulb is fed ·to a voltage-doubler circuit (comprised of Dl, D2, C4, and C5). The output of the doubler is input to the gate of Ql. When the de voltage reaches the gate`s threshold level, Ql switches on, starting the recorder. Resistor R6 sets the circuit`s sensitivity and should be experimented with to obtain the optimum adjustment.

Digital Sound activated Switch Circuit Diagram