I started reading this book and was reminiscing my college days when we had a great time at 'Electronics' Lectures which were fun. I recollect this very quote that had to be memorized for remembering the color codes of Resistors and Capacitors.
Bill Brown Realized Only Yesterday Good Boys Value Good Work (capital letters stand for colors: Black 0 Brown 1 Red 2 Orange 3 Yellow 4 Green 5 Blue 6 Violet 7 Grey 8 and White 9)
Some Definitions for the layman:
Microphone - A microphone is an electro-acoustic transducer. It converts acoustic energy (sound vibrations) into electrical energy (audio frequency electrical vibrations)
Radio Transmitter - produces radio frequency energy that is controlled by the intelligence to be transmitted.
Transmission Lines- is a device to transmit high frequency electromagnetic energy from a given source(generator) to the load(antenna)
Antenna is a device composed of a system of one or more linear conductors, the dimensions of which vary from a fraction to several wavelengths. The higher the frequency, the shorter is the required length of the antenna conductor
Multimeter - is an electronic instrument to measure voltages (ac and dc), currents (ac and dc) and resistances.
Television - is the art of transmission and reproduction of moving figures at a distance. The light intensities from the illuminated object are converted into the electrical fluctuations. These vibrations are called video signals after amplitude modulation are transmitted by the antenna. At the receiver, the signal after demodulation is applied to a device which reproduces the transmitted picture. The first part is known as iconoscope and the latter kinescope.
RADAR - is the abbreviation for Radio Detection and Ranging It is not a single instrument but includes various techniques. A short burst or pulse of electromagnetic radiation is transmitted from a highly directional antenna, when this transmitted radiation hits a distant target, a part of the radiation is reflected back and an echo pulse is picked by a receiver. The time interval between transmitted and echo pulses provides an accurate measure of the target distance. The function of the radar system is very precise, rapid and unaffected by darkness, clouds, fog, etc.
Electron Microscope - is a device to magnify minute objects similar to optical microscopes. A beam of electrons is employed instead if light rays because, i) Electrons have a wave nature, similar to light rays but of much shorter wavelength and ii) Electrons can be focused by electric and magnetic fields, very like rays which are focussed by glass lenses. The resolving power of the electron microscope can be greatly increased without decreasing perceptibility.
LASER - 'Light Amplification by Stimulated Emission of Radiation' - Applications:
1. A controlled laser beam is used in medical surgery e.g., photo-coagulator (treatment of detached retinas), dentistry (treatment of teeth), controlled dosages, destroying cancerous cells, tumours and skin scars)
2. The laser is used in Industry. e.g., in machining, welding and cutting operations
3. The laser beam is used in chemical applications, e.g., to hasten or initiate chemical reactions.
4. The laser beam has been widely used in communications between earth and satellites on account of narrow bandwidth, high intensity and high frequency
5. The laser beam is being developed in military to serve as a war weapon and as blind vision detectors for directing planes and missiles.
6. The monochromaticity of a laser is important in spectroscopy and photography
7. Laser Raman Spectroscopy has grown rapidly as some special effects such as resonance Raman effect, stimulated Raman effect, inverse Raman effect, hyper Raman scattering can be studied with the help of laser beams only.
8. Laser beams are used in holography, the three dimensional photographic process.
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