[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors ...

This is an Infrared beam breaking alarm ideal to use in entry or passages.It is based on the working of the popular IR sensor Module TSOP 1738 which senses 38 kHz Infrared pulses from the IR LED of ...

I set up my $25 WyzeCam v2 with the PIR Motion Sensor and Sensor Bridge accessory to catch some hummingbirds feeding. I can't use video motion detection because the feeder is constantly swaying in the ...