In this post I have explained a simple LDR brightness and efficiency tester circuit set up using an LDR and a digital Ohm meter. The idea was requested by Mr. Prashant Technical Specifications I want to check brightness and light of 1 watt led. Can i check it with help of ldr. Bekoz luminous sensor […]
LED
Semiconductor Tester Circuit [LED, Transistor, SCR Tester]
The semiconductor tester circuit I have explained below performs continuity tests on SCRs, bipolar transistors, and diodes. How the Circuit Works A squarewave oscillator with a frequency of about 350 Hz is produced by a couple of IC 4049 gates, U1a along with U1b, R1, R2, and C1. The complementary outputs required for testing both NPN and […]
Christmas LED Candle Light Timer Circuit
In this post I have explained a sequentially advancing 25 LED timer circuit which may be initiated on the 1st day of December so that each LED lights up on each day until the 25th of December (on Christmas) when all the 25 LED can be seen lit up. The circuit was requested by Mr. […]
Rotating Beacon LED Simulator Circuit
In this post I have explained a simple LED flashing beacon circuit which exactly simulates a rotating police beacon light by generating alternating pulses of suddenly rising and fading illumination effect on the connected LED. The idea was requested by Mr. Ankit Agarwal Technical Specifications Can you advice on how to make the following circuit […]
Rechargeable LED Lantern Circuit Using Dynamo
In this post we study a simple rechargeable LED lantern circuit which features battery charging option from a dynamo as well as from a mains 220V source. The idea was requested by Mr. Chidimonday. Technical Specifications I like what you doing here, i have even put in work some of your circuit and it functioned […]
Simple Scrolling RGB LED Circuit
A simple RGB (Red, Green, Blue) moving or scrolling LED display can be made using a few 4017 ICs. I have explained the procedure in detail. Understanding RGB LED RGB LEDs have become quite popular these days due to its three-in-one color feature, and because these can be driven independently using three distinct supply sources. […]





