This LED light bar with dimmable feature will allow the user to adjust the brightness of the lamp in 4 steps, with100%, 50%, 10% and 0% illumination control at each subsequent steps. The idea was requested by one of the avid readers of this blog. Here’s the required working concept. The Design The basic design […]
Archives for 2020
Stud Finder Circuit – Find Hidden Metals Inside Walls
A stud finder is an electronic device specially created for scanning concrete walls and locating metallic objects, such as nails, bolts, pipes, hidden beneath the wall. In the following post I have explained a very simple two-transistor metal detector that you can assemble in an afternoon or two and have fun with using for hours […]
Signal Injector Circuits for Quick Troubleshooting of all Audio Equipment
This simple signal injector circuits I have explained below can be accurately used for troubleshooting and alignment applications of all kinds of audio and high frequency equipment. 1) Using a Single IC 7400 One of the extremely handy devices for repairing audio and high frequency instruments is without question a equipment that will give you […]
Adjustable Drill Machine Speed Controller Circuit
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 […]
Touch Alarm Circuit
The touch alarm circuit senses the mains hum signal from an intruder’s body and raises the alarm sound. This happens whenever an intruder touches a potential element set as the sensor, such as the door knob, or any object that needs to be protected. If the circuit is linked with the door knob, the circuit […]
Remote Control using Mains Power Line Communication
The proposed circuit will allow you to remotely control a mains AC operated appliance across rooms of your home through mains power line communication or PLC concept. In PLC technology, an electronic circuit which works as a transmitter is plugged-in to the mains wiring (220 V or 120 V) injects a modulating high frequency data […]





