This Simple Shadow Detector Security Circuit is like one guard with very sharp eyes. It uses one light sensor like photodiode to look shadow in one place. If something stop the light and make shadow then the circuit think someone is there and start an alarm. Alarm can be loud sound, blinking light or something […]
Simple Storm Detector Circuit
Simple Storm Detector Circuit is like small weather magic in box. It can feel lightnings electric noise which shows storm is coming near. This circuit uses one antenna to catch small signal in air like small radio. But signal being weak it uses amplifier to make signal strong. Sometimes it also uses special filter to […]
Ultrasonic Security Alarm Circuit
Ultrasonic Security Alarm Circuit work like invisible wall for ones home. It uses very high sound wave like tiny squeaky noise which human ear can not hear it uses this to find the movement. Think like circuit sends sound wave then it waits to hear echo come back. If someone walk in the way and […]
Wireless RF Network Cable Tester Circuit
Wireless RF Network Cable Tester Circuit is like X-ray for internet wire. It can catch radio signal inside cable like ethernet, modem or satellite TV but there is no need to touch the wire. It is very easy to use for checking cable working or not. Just hold tester near the wire and it will […]
Simple Temperature Meter Circuit
Simple Temperature Meter Circuit is like small detective for heat. It use special sensor like thermocouple or thermistor to feel heat near it. Sensor can be small part or smart chip like LM35 or LM34 which change heat into electric signal. Then circuit take this signal and confirms how much hot or cold it is. […]
Simple Radiation Sensor Circuit
Simple Radiation Sensor Circuit is like small spy for rays which one cannot see. It can smell different radiation like from light bulb, electromagnetic, or X-ray (ionizing one) etc. This circuit have special sensor when radiation detects sensor feels it and send signal. The circuit then uses that signal to modify things such as showing […]