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 […]
Electronics Theory
How RC Circuits Work
In an RC circuit, a combination or R (resistor) and C (capacitor) is used in specific configurations in order to regulate the flow of current, for implementing a desired condition. One of the main uses of a capacitor is in the form of a coupling unit which allows AC to pass but blocks DC. In […]
Diac – Working and Application Circuits
The diac is a two-terminal device having a combination of parallel-inverse semiconductor layers, which allows the device to be triggered through both directions regardless of the supply polarity. Diac Characteristics The characteristics of a typical diac can be seen in the following Figure, which distinctly reveals the presence of a breakover voltage in across both […]
Unijunction Transistor (UJT) – Comprehensive Tutorial
A unijunction transistor is a 3 terminal semiconductor device which is unlike a BJT has only a single pn junction. It is basically designed to be used as a single-stage oscillator circuit for generating pulsed signals suitable for digital-circuit applications. UJT Relaxation Oscillator Circuit The unijunction transistor could be typically wired in the form of […]
Solid State Relay (SSR) Circuit using MOSFETs
SSR or Solid state relays are high power electrical switches that work without involving mechanical contacts, instead they use solid state semiconductors like MOSFETs for switching an electrical load. SSRs can be used for operating high power loads, through a small input trigger voltage with negligible current. These devices can be used for operating high […]
Reed Switch – Working, Application Circuits
In this post I will comprehensively explain about reed switch functioning, and how to make simple reed switch circuits. What is Reed Switch Reed switch also called reed relay, is a low current magnetic switch with a concealed pair of contacts that close and open in response to magnetic field near it. The contacts are […]
