Have fun making this Simple Lie Detector Circuit using Transistors. Real lie detectors are very hard and complicated so this one is not perfect. But it is fun way to see how body react when stress. This circuit works by checking sweat changes to know if someone tell truth or lie. When people are scared […]
Sensors and Detectors
Simple RF Sensor without Battery Circuit
This article for Simple RF Sensor without Battery Circuit show how to make small tester with no battery. It help check if radio transmitter is working or not. The tester get power from radio waves which is sent through transmitter. If transmitter works LED light will blink to show it. What is a RF Sensor […]
Simple Metal Detector Circuit
This article show a special trick to make a Simple Metal Detector Circuit It uses simple circuit not like other circuits and needs only one transistor. The circuit find metal by catching signal from a normal radio. What is a Metal Detector: Metal detector is electric circuit made to check if metal is close or […]
Simple Magnetic Field Sensor Circuit
This is an Easy and Simple Magnetic Field Sensor Circuit. It can find magnet near the sensor. This circuit is easy to make and is good for beginners. We can learn how it work and use in small projects which is very fun and useful! What is a Magnetic Field Sensor: Magnetic field sensor circuit […]
Infrared (IR) Sensor Alarm Circuit using TSOP1738
This tutorial show how to make a Infrared (IR) Sensor Alarm Circuit using TSOP1738. It finds intruder using light which we cannot see. This alarm uses infrared light so people call it IR alarm. It make one invisible light beam with small chip named IC 555. If someone walk in front of light, then the […]
Sound Activated Relay Circuit
This article show how to make one Sound Activated Relay Circuit. It uses sound for turning device ON and OFF. Relays are special parts and they control big power things like lights and motors. Here are some ways to use it: This article tell how to build and use this type of circuit. of circuit. […]