This article is about is a Simple Transistor Based Touch Switch Circuit. It works when finger touches the pad with no push button used. Human body gives small signal and circuit senses this signal. Two NPN transistors are used and one LED is used as output. Circuit works with only 3V supply which is very […]
Transistor Circuits
Simple 12V Battery Charger Circuit using TIP41 Transistor
This is a Simple 12V Battery Charger Circuit using TIP41 Transistor. It uses one NPN power transistor TIP41 and one 13.8V Zener diode. The circuit is cheap, easy and safe for charging 12V lead acid battery. This circuit works for small 7Ah to 20Ah batteries. It is a good circuit for learning basic battery charging. […]
Natural Bird Sound Generator Circuit using Transistors
This is a small Natural Bird Sound Generator Circuit using Transistors. The circuit uses two BC547 transistors, some resistors, capacitor and a speaker. It is simple for beginners and works on low voltage like 3V to 9V. Circuit is good for toys, hobby projects, alarms and for school projects. Circuit Working: Parts List: Item Value […]
Laser Security Alarm Circuit using LDR and BC547 Transistors
This project is for Laser Security Alarm Circuit using LDR and BC547 Transistors. It uses LDR, two BC547 transistors, one diode and a buzzer. When laser light breaks an alarm rings. Circuit is cheap and very easy to build. Good for door security, box security and drawer protection. Circuit Working: Parts List: Component Value Quantity […]
Smart Street Light Control Circuit
Light ON at night and light OFF in day all automatic! All this is done with one LDR and a BC547 transistor. This Smart Street Light Control Circuit is a easy and simple way to save energy. There is no manual effort and no energy waste. Circuit Working: Parts List: Component Name Specification Quantity Resistors […]
LDR Based Dark Sensor Circuit
This small LDR Based Dark Sensor Circuit is very smart. It can see light and dark using LDR. When there is light, everything stay quiet. When it becomes dark then LED start to glow and buzzer makes sound. No need to touch anything it works by itself. It is easy to make with low cost […]