In this article we’ll study a digital stopwatch design configured around the very popular IC LM555 in conjunction with a 4-digit counter IC with multiplexed 7-segment output drivers (MM74C926). Written and Submitted by: Jennifer Goldy Circuit Operation IC MM74C926 is internally made up of a 4-digit counter, an output latch up stage, a npn output […]
Games and Sports Projects
Make a Football Electricity Generator Circuit
The explained football electricity generator circuit was developed by me in response to the request sent by one of the readers Mr.Bright. Though I am not sure if the explained concept would actually give the intended results, it’s worth trying as it’s quite easy to understand and build. Designing the Generator There were three things that I had to consider while designing the […]
10 LED Simple Roulette Wheel Circuit Diagram
A very simple 10 LED roulette wheel circuit is shown here. pressing the button starts the LEDs in a rotational motion (sequencing) at full swing initially, and gradually slows down, until it stops to a particular, randomly selected LED. The randomness of the selection depends upon the time for which the push remains switched ON […]
5 Simple Fastest Finger First Circuits Explained
The 5 simple fastest finger first indicator circuits presented here can be used for indicating which candidate was the first to press the answer button out of the 4 participating candidates in a quiz contest. We all have probably seen the famous game show “who wants to be a millionaire” and many similar quiz shows, […]
Tennis Ball Throwing Machine Circuit
In article below explains the control circuit for an automatic tennis ball throwing machine, designed to throw a tennis ball through a mechanized catapult machine, controlled with powerful motors. In this article I have explained the motor control circuit which will toggle the catapult mechanism back and forth, with a 2 second time interval, while […]
Random LED Number Generator for Gambling Application
In this post I have explained a random LED number generator circuit consisting of a 4 x 5 LED matrix, numbered from 1 to 20. On pressing a push button these LEDs begin illuminating randomly, until finally a single LED corresponding to a specific number remains illuminated. Thus, this random LED number generator can be […]





