Headphone Amplifier Circuit using Transistors make weak sound strong so headphones work well. This circuit is useful when sound is direct from source which is not loud or clear. In this post we talk about small 3V transistor amplifier for better sound. Circuit Working: Parts List: Component Type Value/Specification Quantity Resistors (All resistors are 1/4 […]
Transistor Circuits
High Current 12V Voltage Regulator Circuit using Transistor
Voltage regulators is very important in power supply. They keep voltage steady and even if input voltage changes or load changes. This circuit give steady 12V output with max 3A current. If current need more than 3A then it still works good for regulation. High Current 12V Voltage Regulator Circuit using Transistor give steady 12V […]
Transistor Based Stepper Motor Drive Circuit
Stepper motors are good for robots, CNC, automation and to move very exact. Transistor Based Stepper Motor Drive Circuit run unipolar motor with logic gates and transistors. It use four 2N2222 to control motor windings, two NOT gates, one XOR gate and to read 2-bit control to turn ON 4 windings. Circuit needs parts like […]
Temperature Based DC Fan Controller Circuit using Transistors
Temperature Based DC Fan Controller Circuit using Transistors turns ON when hot, stops overheating and saves energy. Thermistor checks temperature and runs fan as needed. The circuit works on 12V battery or 12V power supply. Circuit Working: Parts List: Component Type Value Quantity Resistors (All resistors are 1/4 watt unless specified) 1.5k 1 1k 1 […]
Transistor Based H-Bridge Motor Controller Circuit
Transistor Based H-Bridge Motor Controller Circuit controls DC motor spin both ways like clockwise, anticlockwise. The circuit helps control speed and direction by easy switch method. Name “H-Bridge” comes from shape like letter H which has 4 switches. In this post circuit is 4-transistor H-Bridge. Circuit is good for robotics, automation and other motor projects. […]
Simple Time Delay LED Circuit using Transistor
This article is about Simple Time Delay LED Circuit using Transistor where the LED lit after a short wait. The circuit needs transistor, capacitor and few resistors for delay. It is good for power light, warning light and timing project. It work with 10V DC and fits many electronics. Circuit Working: Parts List: Component Specification […]





