In this post I have explained a simple automatic PIR controlled ceiling fan circuit for school college use, which responds and switches ON only in the presence of a human (students) in the classroom. The idea was requested by Mr. Souren Bhattacharya. Technical Specifications I am, souren bhattacharya, a high school teacher in west bengal. […]
Newly Updated Circuit Projects:
Ultrasonic Smart Automatic ON/OFF Switch Circuit
In this article we are going to build a smart automatic ON/OFF switch using Arduino, which can turn on or off gadgets automatically by sensing the presence of human nearby through the concept of ultrasonic. We are going to use ultrasonic module and Arduino to sense the presence of human which activates the gadgets such […]
Ultrasonic Pest Repellent Circuit
The explained Ultrasonic Pest repeller is a device that generates ultrasound or a very high frequency noise in the range of over 20 kHz which becomes useful for repelling or scaring away animals like stray dogs, cats, mice bats, etc. This becomes possible since these animals are able to easily detect the frequencies at this […]
Ultrasonic Detector Circuit [Extend your Ear’s Sensitivity]
The ultrasonic detector or receiver circuit will be able to detect all those high frequency sounds that are beyond the hearing capacity of humans. The units will be able to hear all those frequencies that are perhaps only audible to some animals like dogs, cats and bats. The ultrasonic receiver circuit can be used for […]
How Switch Mode Power Supply (SMPS) Circuits Work
SMPS is the acronym of the word Switch Mode Power Supply. The name clearly suggests that the concept has something or entirely to do with pulses or switching of the employed devices. I have explained how SMPS adapters work for converting mains voltage to a lower DC voltage. Advantage of SMPS Topology In SMPS adapters […]
Cheapest SMPS Circuit Using MJE13005
The explained circuit in this article is probably the simplest and the cheapest, since it employs minimum number of components and the making of the circuit is very straightforward. Circuit Operation Generally SMPS topology involves some fixed standard stages and criteria. Thgey may be listed in the following manner: The first stage which is the […]





