Category Archives: Security



Car Audio System Anti Theft Security

This is the circuit diagram of car audio system anti theft security which can be effectively used to protect and secure your expensive car audio system from stealing. This simple circuit designed based on popular CMOS NAND chip CD4093,. When the circuit is switched on via switch S1, the indicator LED1 will glow and the… Read More »

Laptop / Notebook Protector

This is laptop / notebook protector circuit to protect your laptop or notebook or netbook from being stolen. Fixed in-side the laptop case, it will sound a loud alarm when someone tries to take the laptop. This highly sensitive circuit uses a homemade tilt switch to activate the alarm through tilting of the laptop case.… Read More »

Electronic Appliance Protector

This is a easy built and very low-cost circuit purposed to protect your electronic appliances / devices, such as Personal Computer, TV, recording devices, refrigerator, and other devices during sudden tripping and resumption of home mains supply. Appliances like refrigerators and air-conditioners are more inclined to damage due to such conditions.

Shutter Guard

This is the shutter guard circuit which has sensitive vibration sensor, piezo-sensor. This circuit is specifically designed for outlets to defend towards theft. It can recognize any mechanical or acoustic vibration in its area when somebody attempts to break the shutter and instantly turn on a lamp and sound an alert alarm. A 15-minute time… Read More »