Tired of torn-up flower beds, Hap took matters into his own hands by combining a sprinkler and wireless driveway alert system. To allow enough time for the sprinkler valve to open, build pressure, and activate the sprinkler head, he constructed a time-delay unit from an old standby 555 timer. It activates the sprinkler valve with ac power from the control for 10 to 12 seconds — allowing plenty of time to open and apply a good H2O dousing to varmints and wayward mailmen alike. Scroll down to view a video demonstration and the parts list.
Timer Delay Circuit for Motion Detection System
Allied Part #
555 Timer IC
SPST Mini Switch
5V dc DPST Relay
470 ufd Capacitor
5 ufd Capacitor
10 ohm Resistor
100 ohm Resistor
1 Kohm Resistor
15 Kohm Resistor
Additional parts required: Reporter Wireless Alert System with (1) Transmitter and (1) Receiver; Optima Sprinkler Control Panel
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