In this post I have explained the basic working concept of thermal scanners or contactless IR thermometers, and also learn how to make a practical DIY prototype of the unit without Arduino. In the post COVID-19 era, witnessing doctors holding a contactless temperature gun and pointing toward the forehead of a COVID-19 suspect is a […]
Newly Updated Circuit Projects:
Simple Triac Triggering Circuits Explained
In this post I have explained the fundamental methods of triggering a triac, and also discuss the right way to connect the terminals of a triac. Triacs are solid-state bidirectional thyristors that can switch across both the AC half cycles on a 120-volt or 240-volt Ac power system. A triac could be activated (switched on and […]
Understanding MOSFET Avalanche Rating, Testing and Protection
In this post I have explained MOSFET avalanche ratings, and learn how to understand this rating in the datasheet correctly, how the parameter is tested by the manufacturer, and measures to protect MOSFETs from this phenomenon. The avalanche parameter not only helps to verify the devices ruggedness, it additionally helps filtering out weaker MOSFETs or […]
High Stability of Crystals in Oscillator Circuits
The stability of good quality RC oscillators can be expected to be around 0.1%, while normally we can assume the stability of LC oscillators to be up to 0.01%. When a much higher level of stability is required, we have to use a crystal based oscillator circuit. The main reason why crystals are so important […]
Clipper and Clamper Circuits Explained
In this post I am going to explain clipper and clamper circuits. The clipper and clamper are called wave shaping circuits because they convert the incoming signal wave to another kind of useful wave. They are used widely in power supplies, filter circuits, RF transmitters / receivers, voltage suppressors, audio amplifiers and the list goes […]
What is a Gunn Diode? How it Works?
Gunn diodes are semiconductor devices which are used to generate low-power microwave signals in a simple and low-cost manner. These have been in use for more than 60 years now. Gunn diodes can work with frequencies ranging from a few gigahertz to over 100 GHz. It was first discovered by J. B. Gunn of IBM […]





