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Security and Protection

Luggage Safety Alarm Circuit using IC LM358

Last updated on 3 September 2025 by Admin-Lavi Leave a Comment

Today security is big problem everywhere. Many time thief try to open bag or suitcase in bus, train or station. We cannot always watch our luggage. This small Luggage Safety Alarm Circuit using IC LM358 help to protect our bag. It uses piezo sensor and LM358 to sense vibration. When someone touches or try to […]

Filed Under: Alarm Circuits, Security and Protection

Simple Wire Loop Security Alarm Circuit

Last updated on 23 August 2025 by Admin-Lavi Leave a Comment

Simple wire loop alarm is small security circuit. It uses thin wire as sensor loop. If loop is cut or opened the buzzer will sound. It works on 9V battery, needs few parts, is cheap and easy to make. Circuit Working: Parts List: Component Specification Qty Resistors 4.7M 1/4 watt 1 100k 1/4 watt 1 […]

Filed Under: Alarm Circuits, Security and Protection

Simple Dark Sensor Circuit for Security using IC 555 timer

Last updated on 12 August 2025 by Admin-Lavi Leave a Comment

Simple Dark Sensor Circuit for Security using IC 555 timer is useful project for security. It senses low light and turns ON the buzzer or light. It is used for LDR as light sensing. Circuit is good for night light and alert system. The circuit have parts like 555 IC, LDR, resistors, capacitor and buzzer […]

Filed Under: Security and Protection, Sensors and Detectors, Timer Circuits

Simple 555 Timer Based Animal Repeller Circuit

Last updated on 8 August 2025 by Admin-Lavi Leave a Comment

Simple 555 Timer Based Animal Repeller Circuit is small device to keep animals away. It make high sound which animals do not like and humans mostly do not hear it. Main part is IC 555 timer which make high frequency sound. Sound is around 15 kHz to 120 kHz (ultrasonic). This circuit is easy to […]

Filed Under: Security and Protection, Timer Circuits

Build Our Own Solder Fume Extractor Circuit

Last updated on 1 August 2025 by Admin-Lavi Leave a Comment

Soldering make bad smoke which is not good for health. So every work table need good smoke remover. To Build Our Own Solder Fume Extractor Circuit uses few easy parts to remove bad smoke. It uses BC547 transistor, small DC fan, preset resistor, capacitor and NTC thermistor to make air clean and safe. NTC thermistor […]

Filed Under: Security and Protection

Build Your Own Door Knob Touch Alarm Circuit

Last updated on 31 July 2025 by Admin-Lavi Leave a Comment

Todays time safety is very important. This Build Your Own Door Knob Touch Alarm Circuit can help protect home and office. This small project is Door Knob Touch Alarm using 555 IC. It can sense when someone touches the door knob. If someone touches then alarm makes loud sound. It scares intruder and warn owner […]

Filed Under: Alarm Circuits, Security and Protection

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