The proposed variable drill speed controller circuit maintains a constant (adjustable) speed over the drill machine motor, regardless of the load. One of the most used power tools is the power drill machine. Despite its innumerable advantages, the power drill has one major setback – constant high speed for many applications. Even when there are […]
Newly Updated Circuit Projects:
Simple Tone Control Circuits
Tone control circuits are basically filter circuits which are used to filter audio frequency signals so that only the desired range of frequencies are allowed to pass to the amplifier and the loudspeakers. This enables the listener to customize the music output with either a high level of low frequency content through bass boost, or […]
5 Simple Preamplifier Circuits Explained
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 […]
Balanced Microphone Preamplifier Circuit
In this post I have explained about a simple Hi-Fi balanced microphone preamplifier circuit and also evaluate the calculations, specifications of the design through formulas. What is a Balanced Preamplifier A “balanced” amplifier or differential amplifier possesses not one but two distinct inputs and only the difference amongst these inputs is actually amplified. To elucidate […]
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 […]





