A circuit which enables a user to linearly control the speed of a connected motor by rotating an attached potentiometer is called a motor speed controller circuit. 5 easy to build speed controller circuits for DC motors are presented here, first one using MOSFET IRF540, second one using IC 555, the third concept with IC […]
Simple
5 Simple DIY Inverter Circuits you can Build at Home
Making a simple DIY inverter circuit is very easy if you have a few transistors (BJTs), MOSFETs or one oscillator IC. The main work of all these circuits is same. They take direct current from battery and change it into alternating current using transformer and some switches. Different types of circuits are there to make […]
5 Simple Motion Detector Circuits using PIR
A PIR motion sensor alarm is a device which detects the infrared radiation from a moving human body and triggers an an audible alarm. In this post I have explained 5 simple motion detector circuits using op amp and transistor. We also discuss the pinout details of the standard passive infrared (PIR) sensor RE200B. We […]
Simple Transformer Winding Tester Circuit
This test set is primarily designed to test step-down, step-up transformers, for open and shorted winding. It can determine if the device under test has a low resistance to ac current. It can also measure the dc current resistancein ohms. By Henry Bowman Introduction The test set uses a 16 VAC, 60hz signal to determine […]
Simple MOSFET Tester and Sorter Circuit
This simple MOSFET tester does a quick job of testing both enhanced mode type N and P-channel mosfets. It checks for shorts between gate, drain and source. Designed By: Henry Bowman It also distinguishes between N and P-channel mosfets. Once the connections are correctly made to the mosfet, all testing is done without reversing connections. […]
Simple Transistor Diode Tester Meter Circuit
In this post I have explained how to make a simple yet efficient transistor/diode tester circuit, that will not only test the quality of a BJT, but will also help to identify whether it is is an NPN or a PNP. The circuit was designed and contributed by Mr. Henry Bowman. Circuit Operation Referring to […]





