As the name suggests a preamplifier circuit pre-amplifies a very small signal to some specified level that can be further amplified by an attached power amplifier circuit. It basically acts like a buffer stage between the input small signal source and a power amplifier. A preamplifier is used in applications where the input signal is […]
Circuits
Simple 10 Watt Amplifier Circuits using Transistors
In this post I will comprehensively explain 3 easy to build 10 watt power amplifier circuits, which can be built using discrete parts, such as resistors, transistors, and MOSFETs. The MOSFETs used in these designs are the ordinary IRF540 and IRF9540, that are easily avail;able in the market and are quite inexpensive. True Complementary 10 […]
Op Amp Preamplifier Circuits – For MICs, Guitars, Pick-ups, Buffers
In this post I have explained a variety of op amp preamplifier circuits, and there should be an appropriate layout here for almost any standard audio preamplifier application. As the name suggests itself, a preamplifier is an audio circuit which is used before a power amplifier, or between a small signal source and a power […]
Simple Mini Audio Amplifier Circuits
In this article we are discussing a handful of simple, mini audio amplifier circuits which can be built quickly for amplifying very tiny input signals into audible speaker outputs. 1) 1 Watt Amplifier Circuit The first simple mini audio amplifier circuit works with a ‘complementary’ output stage, having a single NPN and a single PNP […]
Simple Buck Converter Circuits using Transistors
In this post I have explained some basic facts about DC to DC buck converters and also learn how to build a simple buck converter circuit. A buck converter is also popularly known as a step-down converter, since its basic function is to step down a higher input voltage level to a lower output voltage […]
Temperature Controlled DC Fan Circuits
Have you ever turned up your amplifier all the way, either at a party or just for fun? You may have noticed that “it gets hot” and thought that a fan would be useful. However, at low listening levels, you can hear the fan running. With this circuit, the fan will be automatically controlled by […]





