SOUND ACTIVATED SWITCH – RELAY

This project is a sound-activated switch.

DESCRIPTION

Clap switch/Sound-activated switch designed around op-amp, flip-flop, and popular 555 IC. Switch avoids false triggering by using a 2-clap sound. Clapping sound is received by a microphone, the microphone changes the sound wave to an electrical wave which is further amplified by the op-amp.

555 timer IC acts as a mono-stable multi-vibrator then flip-flop changes the state of the output relay on every two-clap sound. This can be used to turn ON/OFF lights and fans. The circuit activates upon a two-clap sound and stays activated until another sound triggers the circuit.

Specifications:

• Supply 12V DC @ 60mA
• On board preset to set the sensitivity
• On board LED to indicate the Relay on/off state
• On board Microphone
• Relay switch 5Amps, 110V-230V

SCHEMATIC

PARTS LIST