Circuit Category: Fun Circuits

220V Light Dimmer circuit diagram

This simple 220V light dimmer circuit can be used to adjust the brightness of mains lights. It also can be used to adjust the speed of AC motors. It uses a triac, diac and has a radio-frequency interference (RFI) noise suppression circuit built into it as well.

Schematic diagram:

220V Light Dimmer circuit diagram

Component part:
R1 = 10K
R2 = 2K2
R3 = 180K
Potentiometer 250K
C1 = 150nF/400V dipped polyester
C2 = 47nF/630V  dipped polyester
C3 = 220nF/250V AC dipped polyester
Triac = 2N6075 or BT136-500D
Diac = HT-32
FUSE 2A or 3A

Sound Activated Switch circuit diagram

This is a sound activated switch circuit. It’s will turn on and turn off based on a loud sound such as clapping your hands. You can adjust the sensitivity (how loud of a sound will activate the circuit) from a pin drop to a Mack Truck Horn. Very practical for a variety of projects. Add a relay to turn on a light when your dog barks, or set of a siren when an intruder makes a loud noise.

Here the circuit diagram:

Sound Activated Switch circuit diagram

Component Part:

R1, R5, R16 = 10kΩ
R3 = 22kΩ
R2, R6, R9, R13 = 220kΩ
R4, R10, R12, R14 = 100kΩ
R7 = 270kΩ
R8 = 4.7MΩ
R11 = 1MΩ
R15 = 330kΩ
R17 = 4.7kΩ
P1 100kΩ Trim Pot
C1, C3 = 10nF
C2, C4 = 100nF
C5, C6, C8, C9 = 1nF
C7 = 1μF/16V Electrolytic
C10 = 100μF/16V Electrolytic
Q1 = 2N3904
Q2 = MPS6531
U2 = 4001 Integrated Circuit
U1 4011 Integrated Circuit
LED = LED Red
MIC = Electret Microphone

220V LED Flasher circuit diagram

This is a 220V LED flasher circuit which is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing. This a cheap circuit and easy to build.

Schematic diagram:

220V LED Flasher

Component Parts:

R1_________ 100K
R2,R5______ 1K
R3,R6______ 470R
R4_________ 12K
C1_________ 1000µF 25V
D1-D4______ 1N4007
D5_________ SCR  P0102D
Q1_________ BC327
Q2_________ BC337
SK1________ Female Mains socket