Arduino Sound Operated Light — the clap switch, done properly
Everyone knows the clap switch. This version does it the right way: instead of a fragile analogue circuit, a microphone sound sensor module feeds a real microcontroller, so the response is clean and repeatable, and a relay module does the actual switching. That means it drives a genuine bulb, not just a tiny indicator LED — which is exactly what makes it convincing in front of a class or an examiner.
How the circuit works
- The sound sensor module listens for a sharp sound and pulses its digital output when the clap crosses the threshold.
- The Arduino Uno reads that pulse and toggles its stored on/off state.
- The Uno drives the 1-channel relay module, whose contacts switch the LED bulb.
- The small blue trimmer on the sound sensor sets the sensitivity, so you can tune it for a noisy classroom.
What is on the board
- Arduino Uno R3 microcontroller board
- Microphone sound sensor module with adjustable sensitivity
- 1-channel 5V relay module
- LED bulb with holder
- 9V battery and USB cable for power
- Jumper wiring, all mounted on a printed display board
Perfect for
- School science fairs and working-model competitions
- College practicals on sensors, relays and digital input
- Home-automation coursework and mini projects
- Anyone who wants a demonstration that gets a reaction from the room
Why students buy their project from Arduino Corner
It comes assembled, wired and mounted — no soldering panic, no missing part the night before submission. Drop in and watch it work before you decide.
Visit us: Smart Home | Arduino Corner, Shaheen Market, DAV College Road, Rawalpindi. Same-day delivery across Rawalpindi and Islamabad, cash on delivery all over Pakistan.
