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Transistor Circuits

9V Battery Powered Transistor Intercom Circuit

Last updated on 8 August 2025 by Admin-Lavi Leave a Comment

Intercom system is device for talking at short distance. 9V Battery Powered Transistor Intercom Circuit uses 9V battery which is good for home or office talk. It uses only transistors which is easy to understand and works well. The circuit has mic and small speaker as sound. BC547 transistors make sound loud and 2N2222 transistor […]

Filed Under: Audio Circuits, Transistor Circuits

Transistor Based Battery Heater Circuit

Last updated on 13 August 2025 by Admin-Lavi Leave a Comment

Transistor Based Battery Heater Circuit uses 12V DC with good heat and very portable. Circuit is good for outdoor, no-electric place, small incubator and emergency heat. It uses astable multivibrator with transistors. Transistors switch power transistor and run heat coils. LED show if circuit is working. Circuit Working: Parts List: Component Value Quantity Resistors (All […]

Filed Under: Battery Charger Circuits, Transistor Circuits

Ni-Cd Battery Charger Circuit using Transistors

Last updated on 7 August 2025 by Admin-Lavi Leave a Comment

Nickel Cadmium (Ni-Cd) batteries are very common for rechargeable use. They give good power and work long time with many charges. To charge them right we need a special charger made for Ni-Cd. Mostly it is for 12V Ni-Cd battery pack. This article for Ni-Cd Battery Charger Circuit using Transistors shows simple and strong charger […]

Filed Under: Battery Charger Circuits, Transistor Circuits

Simple Car Headlight Timer Circuit using Transistors

Last updated on 6 August 2025 by Admin-Lavi Leave a Comment

Simple Car Headlight Timer Circuit using Transistors is cool design. It keeps car headlights ON for 1.5 minutes after engine is OFF. It is very useful in dark place which gives light for short time. Circuit uses easy parts like transistors, resistors, capacitor, relay and few more. These all work together for timing. This article […]

Filed Under: Automobile Circuits, Transistor Circuits

12 Watts Amplifier Circuit using Transistors

Last updated on 4 August 2025 by Admin-Lavi Leave a Comment

12 Watts Amplifier Circuit using Transistors make sound louder in audio systems. 12W amplifier uses op-amp with NPN and PNP transistors. It gives strong output for 4 ohm speaker. This circuit is good for audio lovers and boost weak sound to loud, which is clear and with good quality. Circuit Working: Parts List: Component Specification […]

Filed Under: Amplifier Circuits, Transistor Circuits

Simple 555 Timer Based Transistor Tester Circuit

Last updated on 2 August 2025 by Admin-Lavi Leave a Comment

Transistors are very important in electronics. They make signals strong and turn things ON/OFF and do many jobs. To check if its good then we need to test them. Testing helps find problems and broken parts. This article for Simple 555 Timer Based Transistor Tester Circuit show easy way to test transistors with 555 timer […]

Filed Under: Timer Circuits, Transistor Circuits

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