Timing power supply socket circuit controlled by dual electronic meters

Working principle of the circuit: Electronic watch A provides power supply signal. When the alarm signal of watch A arrives
, the audio signal drawn from both ends of the piezoelectric piece passes through R. Make the transistor VT, conduct,
by R. ,C. and Ic,. C. in the RC delay circuit composed of Discharge, point A is at low potential
, and passes through Ic. The inverting output is high level, triggered by IC. The RS flip-flop composed of ICld and ICld
flips, point C is at high potential, and the transistor VT3 is turned on through Rs, the relay is closed, and power is supplied
to the socket . The controlled circuit is powered to work, and at the same time, the LED lights up to indicate power supply. When
the noisy time ends, VT, cuts off, C, stops discharging, passes through Zhan, to C. It returns to high potential after charging
, and IC1a outputs low potential after inversion. The locking function of the circuit is triggered by RS,
point C remains at high potential, and the controlled circuit continues to work. Meter B provides a power-off signal. When the timed
alarm signal of Meter B arrives, it uses the same principle to output a high potential at the IC1b output terminal , triggering the RS flip-flop to flip and reset. Point C is at low potential, VT3 is cut off, the relay is released, the LED goes out, and the controlled circuit is turned off. ZD, R7, and C3 form a simple voltage stabilizing circuit to provide power for the circuit.