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Showing posts from June, 2012

Stuff that dreams are made of

Look up biographies of any of the famous scientists or engineers and you will invariably have come across a common theme: their dads made sure that had access to an encyclopedia. Having interacted with many accomplished academicians, scientists and engineers myself, I find this to be the trend even to this modern day: if the environment is conducive, people carry their dreams from childhood to adulthood and try their best to realize it. The dream imparts meaning to their lives, fuels them ahead and gives them something to believe it. And it is essential that you acquire this dream as early as possible in your life. I became an electronics engineer because I wanted to. I am not yet an expert and only time will tell how good I become at my job. But I love the feeling that you get when you get to do the things that you always wanted to do. I realized that one of the ways I can help kids achieve the same feeling later on in their lives is to help them acquire a dream. A dream in which t

Why is the transistor BC547 so-named?

BC547 is a general purpose NPN Transistor (datasheet here ) which us very popular among hobbyist and engineers alike. But why is it so named? The naming or more specifically “numbering” of most transistors can follow any of the three systems: 1. Pro-Electron (European) 2. Joint Electron Device Engineering Council (JEDEC) 3. Japanese Industrial Standard (JIS) BC547 is a name registered under the Pro-Electron numbering system. The Pro Electron system is the European type designation and registration system for active components, such as electronic tubes and cathode ray tubes, semiconductors, liquid crystal displays, sensor devices, etc. providing concise and unambiguous type designations. The system provides integrity of the designations, and creates transparent and unique product identification, thus preventing confusion in the market place. All Pro Electron type numbers consist of a prefix followed by a serial number. The prefix, generally two or three letters, cl

A simple thermopile

Here is a simple way of demonstrating seeback effect using common electronics lab materials: Cut out a square piece of single sided copper clad board Make vertical groves in it thereby separating the copper into isolated strips Take pieces of solder wire and solder each piece of solder wire on the non copper clad side of the PCB between the ends of two successive copper strip. (Look at the "Thermopile" Schematic here ) If the solder wire you have are thin, you can twist two lengths together to increase the effective thickness like I have done. Dunk one end into pure ice cold water and heat the other end and observe the voltage across the ends of the circuit using a multimeter.