There is a super basic way to build an automatic battery charger using just a few parts. This circuit is like a simple machine for charging batteries by itself. It uses only a transistor a resistor and an LED. It is great for charging things like 9V batteries and even has a light to show […]
Transistor Circuits
Transistor 2N3055 Circuit with 1.5 Million High Gain
The 2N3055 transistor is like a normal volume knob, it can only turn things up so loud. To get super loud like 1.5 million you need to trick it. One way is to use two transistors together like a double volume knob darlington pair. You can even stack more of these double knobs for even […]
Simple Adjustable Zener Diode Circuit
Imagine a tiny switch that controls voltage. A regular zener diode is like a fixed switch it only lets electricity flow past a certain voltage level. An adjustable zener diode circuit is like a fancy dimmer switch for voltage. It uses special parts often a potentiometer to change the voltage level that the switch allows […]
Simple Heat Sensor Circuit using a Single Transistor
This simple heat sensor circuit uses just one transistor and a special resistor that acts like a thermometer. As things heat up, this resistor changes its behavior, which the transistor picks up on. Depending on the temperature, the transistor acts like a gatekeeper letting electricity flow through or blocking it completely. This way, the circuit […]
Simple Low Battery Indicator Circuit Using Two Transistors
This post shows you how to build a tiny helper circuit for your battery powered devices. It uses just a few parts including 2 transistors to light up an LED when the battery is getting low. This way, you will know when it is time to replace the battery before your device stops working. Circuit […]
Simple 300 Watt Power Amplifier Circuit using Transistors
Calling all music lovers who want their speakers to sound REALLY loud! This article shows you how to build a super powerful amplifier circuit that can pump out 300 watts of sound with 8 ohm speakers or even more with 4 ohm speakers. Building circuits with high voltage can be dangerous. If possible be under […]