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Getting the HC-SR501 to function first time

ny51sens last edited by

I have a few HC-SR501 sensors and have not seen any of them function. I connect 5v and gnd to the 3 pin connector, and monitor the output via multiple means. I point the sensor in various directions, and never see it change. I vary the pots, the jumper. Nothing changes.

Please trust I have not been sitting at a bench with the sensor pointing at me all the time I am not using any other circuit at this point, just 5 Vdc, logic probe, scope, etc.

Can someone suggest how to initially set up the HC-SR501 ?
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