An LED music level indicator is a circuit that will respond to the connected music levels and illuminate a chain of LEDs sequentially in a push-pull switching manner, in accordance with the varying music intensity. Since the illumination level of the switching LED chain appear to extend forward and backward proportionately in response to the […]
Archives for 2011
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 […]
Making a Time Machine – Concept Explored
Wondering how to travel in time? Learn it with great Sir Stephen Hawking, according to whom time warp may be an option but seems pretty impractical, the reason being the feed back loop which will just oppose the feasibility of making a time machine and the concept using this theory. Are you intrigued by the […]
How to make a Transistor Latch Circuit
In this post I have explained how to make a simple transistor latch circuit using just two BJTs and a few resistors. Introduction A transistor latch is a circuit which latches ON with a permanent high output in response to a momentary input high signal, and continues to stay in this position as long as […]
220V Solid State Relay (SSR) Circuit using Triac and OptoCoupler
An AC mains solid state relay or SSR is a device which is used for switching heavy AC loads at mains level, through isolated minimal DC voltage triggers, without incorporating mechanical moving contacts. In this post I have explained how to construct a simple mains operated solid state relay or an SSR circuit using a […]
One Transistor Automatic Battery Charger Circuit
This one transistor cheap battery charger circuit is designed to automatically switch OFF the supply to the battery as soon as the battery has reached its full charge level. A very simple single transistor automatic battery charger circuit is I have I have explained in this article, which uses just a single transistor for the […]





