According to school officials, the unintentional intruder alarm caused staff and students to either shelter in place or temporarily evacuate. A spokesperson for the Rockwood School District released ...

This burglar alarm is designed using 555 timer. This circuit is mainly used in homes and offices for security purpose. This circuit is designed to alert the user when an intruder enters into the home.

Patrick Gallagher has a decade of experience testing products from kitchen appliances to home security essentials, focusing on what matters most. Smart home security systems combine the features of a ...

ST CHARLES, Mo. — A new school year is getting underway, and there is much discussion about measures to keep students and staff safe from armed intruders. Child psychologists say conversation is the ...

Cedar Crest High School senior Tyler Steffy was in his first-period class Thursday when the alarm no student wants to hear started ringing in his classroom — “red alert, intruder.” At first, Tyler and ...

The circuit was designed to provide an alarm system against any form of burglary based on the operation of CMOS 4011 where a high output would only result when any of the input is low. The circuit was ...