Clap operated Remote Control for Fans

Here is the circuit of clap-operated remote control fans is used to control not only switching properties but also control speed of fan. The main advantage of clap operated remote control for fan is, it can control up to ten-step speeds of fan where normally a fan has three to five step speeds.

Circuit description clap operated remote control for fan

This entire circuit clap operated remote control for fan is divided into four major section i.e. sound-operated trigger pulse generator, clock pulse generator, clock pulse counter and load operator.

Sound-operated trigger pulse: – The heart of this section is transistor T1 BC148, configured as class-C amplifier mode. The MIC1 is used to change voice signal into its corresponding electrical signal and is given to base of transistor T1 in order to amplify and increase its intensity.

Clock pulse generator:- This section is build around timer IC NE555 and configured as monostable multivibrator. The trigger pulse generated by transistor T1 is given to pin 2 of IC1 and time period (T) for output high is calculated by formula.

T = 1.1RC

Clock Pulse counter:- This section is build around decade counter CD4017BC which counts the clock pulse generated by timer IC (IC1). The output from IC1 is given to pin 14 of IC2. IC2 has ten outputs, viz, o, 1, 2, 3, 4…..9. Here we use only three outputs i.e. output 1, 2 and 3 from pin 2, 4, and 7 respectively. Output 4 from pin 10 is directly connected to reset pin 15.

Load operator:- This section is build around three transistor as relay driver to operate three separate relay. Output from each pin of IC2 is given to base of each transistor through 100Ω and LED as shown in circuit diagram. Output is taken from collector of transistor and is connected to relay. The three LEDs used to indicate gear or speed i.e. LED1, LED2 & LED3 indicates gear 1, gear 2 & gear 3 respectively.

Clap switch



NOTE:-This circuit used to operate in 1st speed similarly, 2nd clap for 2nd speed, 3rd clap for 3rd speed and 4th clap to switch off the fan.


Resistors (all ¼-watt, ± 5% Carbon)

R1 = 10 KΩ

R2 = 1.2 MΩ

R3 = 2.2 KΩ

R4 = 150 KΩ

R5 = 220 KΩ

R6 = 10 KΩ

R7, R8, R9 = 100 Ω


C1, C2 = 0.1 µF/16V

C3 = 4.7 µF/16V

C4 = 0.01 µF (ceramic disc)

C5 = 1000 µF/12V


IC1 = NE555 (Timer IC)

IC2 = CD4017BE (decade counter)

T1 = BC148

T2, T3, T4 = BEL187

D1, D2 = 1N4001 silicon diode


MIC1 = Condenser microphone 34LOD

LED1 = Green

LED2 = yellow


6V-0V-6V, 500mA secondary transformer

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