This circuit lights an electric bulb in darkness. Sensitivity can be controlled using R4. Schematic for gschem.
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Schematic
Parts
R1 | Photoresistor LDR03 (0.1kΩ-2kΩ lit, 1MΩ-100MΩ dark) |
R2 | 2.2kΩ |
R3 | 220Ω |
R4 | Potentiometer, 10kΩ |
R5 | 680Ω |
Q1 | BC547B |
Q2 | BC368 |
U1 | 74L14 (Schmitt trigger) |
T1..2 | Terminals for electric bulb, 6V/2.4W |