TITLE:
Sound operated music bell
CIRCUIT DIAGRAM:
COMPONENTS LIST:
Resistors (all ¼-watt, ± 5% Carbon)
DESCRIPTION:
This is the simple project in which you can turn on door bell just by snapping your fingers.
In this circuit the use of external relay is eliminated.
The circuit comprises of trigger stage (around T1 - BC548B ), a timer stage (NE555), and melody stage (around um66 and sl100).Transistor BC548 is biased in class coperation.Every second sound cause triggering of pin 2 of NE555 ic.When VR1 is at maximum, the hold-on time ofNE555 is arouund 30 seconds.
APPLICATIONS:
Sound operated music bell
CIRCUIT DIAGRAM:
COMPONENTS LIST:
Resistors (all ¼-watt, ± 5% Carbon)
- R1 = 10 KΩ
- R2 = 470 KΩ
- R3 = 2.2 KΩ
- R4 = 150 KΩ
- R5 = 100 Ω
- VR1 = 1 MΩ
- C1 = 22 µF/16V
- C2 = 0.1 µF
- C3 = 0.22 µF
- C4 = 220 µF/10V
- C5 = 0.01 µF
- IC1 = NE555
- IC2 = UM66
- T1 = BC548B
- T2 = SL100
- D1 = 1N4001
- MIC1 = Condensers microphone 34 LOD
- SW1 = On/Off switch
DESCRIPTION:
This is the simple project in which you can turn on door bell just by snapping your fingers.
In this circuit the use of external relay is eliminated.
The circuit comprises of trigger stage (around T1 - BC548B ), a timer stage (NE555), and melody stage (around um66 and sl100).Transistor BC548 is biased in class coperation.Every second sound cause triggering of pin 2 of NE555 ic.When VR1 is at maximum, the hold-on time ofNE555 is arouund 30 seconds.
APPLICATIONS:
- Turn on lights of your study room by just snapping your fingers, instead of searching foe switches.(for this relay will be required.)
- Ring door bell.