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Hardware Required

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You will need the following parts to build this project

1)Decade Counter ICCD40171
2)Voltage Regulator ICLM78051
3)SPDT Relay5V/9V1
4)Condenser Mic1
5)IC Jacket16 pin1
6)NPN TransistorBC5472
8)AC Bulb/Lamp220V1
9)Resistors22K, 1K, 470 Ohms5
10)Soldering Iron45W – 60W1
11)Soldering Flux1
12)DC Battery9V1
13)Battery Clip1
14)Wire Cutter1

bc547 transistor pinout
Pin NamePin No.Description
OUTPUT1-7 & 9-11Pins to receive the output in a sequential manner. (Q0-Q9)
VSS/GND8Ground Pin
CARRY OUT12To connect one or more CD4017 ICs.
CLK INHIBIT13It is used to switch the counter “on” and “off”
CLK14Whenever the CLK pin goes high, it provides the output.
RESET15It is used to reset the counter to zero.
VDD16Positive Voltage Supply pin to IC


1) Solder 5V SPDT Relay onto the PCB Board

2) Solder the IC Jacket for CD4017 on the PCB Board

3) Solder the LM7805 Regulator IC on the PCB Board

4) Solder the LEDs and the 1N4007 diode on the PCB Board

5) Solder BC547 Transistors onto the PCB Board

6) Solder Resistors (R1, R2, R3, R4, R5)

7) Solder the condenser mic on the PCB Board

8) Solder Input (Battery Clips) & Output Connectors to the PCB Board

9) Trim any extra wiring

10) Connect the CD4107 IC & 9V battery, then power up the circuit

11) Test the circuit

Circuit Diagram

Clap Switch CIRCUIT CD4017