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Security and Protection

Fan Start 10 Second Delay Timer Circuit

Last updated on 5 July 2026 by Admin-Lavi Leave a Comment

In many homes and industries sometimes a fan does not turn ON immediately, here, a fan start delay timer is a circuit that delays the fan start. When we apply power, the fan remains OFF for approximately 10 seconds and then turns ON automatically. Also, we can easily adjust the delay time if required. This […]

Filed Under: Automation Circuits, Hobby Circuits, Security and Protection, Timer Circuits, Transistor Circuits

Automatic PIR Motion Sensor Light Circuit

Last updated on 5 July 2026 by Admin-Lavi Leave a Comment

This project explains about a complete Automatic PIR Motion Sensor Light Circuit, it is very useful for home and outdoor lighting, because the circuit uses a PIR sensor. Whenever the PIR sensor detects motion, it turns the light ON automatically and after a preset delay, it turns the light OFF, saving power and reducing human […]

Filed Under: Automation Circuits, DIY Projects, LED and Lamps, Security and Protection, Sensors and Detectors, Transistor Circuits

Simple PIR Sensor Timer Circuit using Transistors

Last updated on 5 July 2026 by Admin-Lavi Leave a Comment

This article presents a simple PIR sensor timer circuit using transistors; the circuit costs little, is easy to build, and operates from a 12 V DC power supply. When the PIR sensor detects motion, the output stays ON for a preset time and then turns OFF automatically after the delay, hence, this feature makes the […]

Filed Under: Automation Circuits, Mini Projects, Security and Protection, Sensors and Detectors, Timer Circuits, Transistor Circuits

Transistor Based Bicycle Tail Light Flashing Circuit

Last updated on 5 July 2026 by Admin-Lavi Leave a Comment

This project presents a simple transistor based bicycle tail light flashing circuit; the circuit primarily functions as a bicycle tail light and operates from a low voltage battery, making it suitable for portable use. Moreover, the circuit uses very few components, because of this its easy to build and also, power consumption is low and […]

Filed Under: Automobile Circuits, Hobby Circuits, LED and Lamps, Security and Protection, Transistor Circuits

PIR Sensor Motion Alarm Circuit Transistor and Relay

Last updated on 4 July 2026 by Admin-Lavi Leave a Comment

Nowadays, security is very important that why homes and shops need protection; so to safeguard this motion sensor circuits are useful. The PIR Sensor Motion Alarm Circuit with Transistor and Relay is simple because it uses only a few components, costs very little, and is easy to build. The circuit works using a PIR sensor […]

Filed Under: Alarm Circuits, Automation Circuits, DIY Projects, Security and Protection, Sensors and Detectors, Transistor Circuits

Simple Infrared Fire Alarm Circuit

Last updated on 1 July 2026 by Admin-Lavi Leave a Comment

This is Simple Infrared Fire Alarm Circuit for beginners, as it use infrared receiver sensor to detect fire heat or flame light. When fire come close sensor output changes and then LED glow and buzzer makes sound; also this circuit is cheap and easy to make. Furthermore, it also uses only few parts like BC547 […]

Filed Under: Alarm Circuits, Mini Projects, Security and Protection, Sensors and Detectors

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