Sensors and Detectors

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 […]

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 […]

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 […]

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. […]

This Simple Non Contact AC Mains Voltage Detector Circuit is to find AC voltage without touching wire. It uses antenna to catch AC signal from air. Then signal goes through transistors and LED blink when AC voltage is near. This circuit is good for safety and easy to make at home. WARNING: Even with this […]