Using the LM3909 this circuit was found in the January 1992 issue of Radio Electronics magazine. Resistor R1 should be chosen according to the table given next to the diagram.
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...