Anti-electric shock verbal warning circuit

Relevant key device information applied in this article: RD627A NE555 LM393 7812 U850 This circuit can be used to prevent electric shock warning in power transformation and distribution facilities. When someone enters the microwave detection range of this device, the circuit will issue a "electrical hazard, please do not "Close" warning sound. The circuit principle is shown in the figure. IC5 is a soft package language integrated circuit. Its appearance and connection diagram are shown in the figure below.