In this project I will show how to construct an air pollution meter using MQ-135 sensor and arduino. The pollution level in the air is indicated by series of 12 LED. If higher the number of LEDs glows, the higher the pollution content in the air and vice versa. Overview This project can prove […]
LED
“WELCOME” LED Display Circuit
In this post I have explained how to make a chasing “WELCOME” display circuit sign board, which illuminates each alphabet sequentially until all the 7 alphabets are lit and then the whole display shuts off, the cycle continues permanently as long as the circuit is powered. Overview I have already discussed a similar concept explaining […]
Sunrise Sunset Simulator LED Circuit
In this post I have explained how to make a sunrise/sunset simulator circuit using LEDs and just a couple of BJTs. The idea was requested by Mr. Jerry Circuit Objectives and Requirements The Design As proposed, a simple sunrise and sunset simulator circuit can be implemented using the circuit shown in the following diagram: The […]
How to Add a Dimmer Facility to a LED Bulb
In this article I have explained how to make an LED dimmer circuit for enabling a dimming facility to any mains operated LEDs bulb. Update: [Using Capacitors, it Works] If you think PWM dimming control might not work for commercial LED bulbs, then the best method is to use series capacitors, which might just do […]
SCR Shunt Circuit for Protecting LED Drivers
The post presents an effective method for protecting capacitive LED driver circuits through an SCR shunt regulator circuit and explains how it can prevent filter capacitors from blowing of and LEDs from getting destroyed. The remedy was requested by Mr. Max Payne. Protecting High Watt LEDs Please suggest regarding 3W, 5W LED bulb circuit design fault. […]
Illuminating an LED using Wireless Power Transmission
In this post I have explained how to illuminate an LED using wireless power transmission. Wireless Power Technology Wireless power is an emerging technology in this present world. But the stunning fact is that it’s a century old concept. This concept was emerged by Nikola Tesla. Charging batteries through wireless power is used in many […]





