We found this circuit in the November 1992 Radio Electronics magazine. The circuit uses an LDR as a sensor and the transistor can be any general-purpose transistor.
Found in an Electronic Design from the 90's, this circuit uses common components. The circuit is...
When the sensor receives light, the relay closes its contacts and remains so even after the light...
This circuit produces pulses of 90 V at intervals that can reach 5 minutes. The circuit is from a...