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:
0 to 50V, 0 to 10amp Variable Dual Power Supply Circuit
In this post I have explained a simple yet very useful 0 to 50V dual power supply circuit which will enable a full 0 to maximum dual voltage +/- control of the input power supply DC. It also includes a wide range current control feature right from 0 to 10 amps. The idea was requested […]
Breath Detector Circuit
The breath detector circuit I have explained below can be used to check or monitor the breathing function of a human or patient. So I have explained the detailed working of the circuit from the following explanation: Component Functions LM324 Op amp: A few operational amplifiers (op-amps) in the circuit magnify the minute voltage changes […]
Mains 220 V AC Line Filter Circuit for Transient Suppression
The 220 V mains AC line filter circuit described here has two functions: it prevents high-frequency waves from being sent back into the power network and it protects connected equipment from power line disturbances and surges. This circuit employs a number of components, such as capacitors, resistors, inductors, and a varistor, which are deliberately positioned […]
Door Security Alarm Circuit for Alerting if Door was Opened
The door security alarm circuit discussed in this article alerts the user whenever the door fitted with the circuit is opened or closed or even moved from its original locked position. Using a Reed Relay and Magnet for the Triggering The idea utilizes the very basic reed relay and magnet concept across the door and […]
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 […]





