Security and Protection

Simple Crowbar Circuit is safety part in electronics. It protect from high voltage spike or surge. Work like fuse but does not burns and it gets short circuit fast to stop damage. It use SCR or TRIAC for shorting, transistor or Zener to trigger. Trigger watch voltage all time. If voltage is too high then […]

Our device is safe from bad voltage by using this Simple Over Voltage and Reverse Voltage Protection Circuit. This circuit uses P channel MOSFET FQP47P06 which better than only diode. Simple diode can stop reverse voltage but not protect from overvoltage or surge. Here the MOSFET and Zener diode give protection. Circuit Working: Parts List: […]

Basic H-bridge PWM circuit uses IC 555 which helps to control dog barking and stop it. Main part is ultrasonic tweeter. It work with two IC 555 and four driver transistors. Circuit Working: Parts List: Category Description Quantity Resistor 1k 1/4 watt 1 Potentiometer 100k 1 Capacitor Ceramic 1nF 1 Semiconductors IC 555 2 Transistors […]

Stun Gun Circuit using IC 555 is simple electric device. It make high voltage for non-lethal self defense. Before making it we must know the danger and law rules to follow. Circuit Working: Parts List: Category Description Quantity Resistors 33k, 1k 1/4 watt 1 each Capacitors Ceramic 10nF, 100nF 1 each PPC 10nF 400V 8 […]

Simple Counterfeit Money Detector Circuit is like smart light. It uses UV light to show secret mark on real note. It also uses magnetic sensor to feel the special ink. Sometimes it uses IR light to see real money pattern. If no special thing is found then maybe the note is fake. But this tool […]

This small and Electronic Gatekeeper Circuit work like little guard for our door. It uses sensor to check if someone comes or goes from gate. Sensor can be like light beam or something we can step on. If person goes through without permission then circuit make alarm or send message to tell us. So we […]