Introduction
It can be said that electronics took birth in 1897, when a vacuum diode was developed by j a Fleming. However the real beginning I was made in 1906. When Lee de forest develop the vacuum triode without the device the amplifier i.e. the heart of all intricateand complex electronic gadgets would not have been made possible.the vacuum tube device dominated the field of electronics and till the end of World war II.
In 1948, transistor was invented by the three novel laurates John bardeen. Walter brattain and William shockley at Bell laboratory. This invention completely revolutionized the electronic industry and opened the floodgates to further development in electronics.Vijay nadikkum and a large number of such device where produce which exceeds the total number of vacuum base device produce prior to 1948.
The development in electronic device goes furtherand the first integrated circuit was appeared in the market during the early sixties. The stringent demand of space electronic resulted in further development in integrated circuit technology starting from small scale integrated circuit, then medium scale integrated circuit,large scale integrated circuit and now recently very large scale integrated circuit have been developed.
The technology of IC is seemingly perfected to its maximum. But are we sure? No!the electronic field in general and the semiconductor device field in particular are so dynamic and so fast changing that today concept may be absolute tomorrow.
Electronics
The word electronic is drive from electron which is present in all materials.the behaviour of an electron under different condition of externally applied field is study under electronic mechanic.
the branch of science and engineering which deals with the flow of electron through vacuum or gas or semiconductor is known as electronics.
in fact electronic is a branch which essentially deal with electronic devices and their utilisation. An electron device is a device in which conduction take place through a vacuum a gas or a semiconductor.
Application of electronics
The electronic play an important role in almost every spare of our life. It has penetrated in every field. Example from an ordinary wrist watch to supercomputer. From telephone repeaters buried deep under sea to the spaceship for out in space, from the control of modern household appliances to the control of 400000 tonne supertanker carrying cargo across the sea.
Electronics dealer in the micro and Milli range of voltage, current and power, but it control kilo and mega volts, ampere and watts.some of the important application of electronic in various fields are given:
Communication and entertainments
in earlier stage the mean application of electronic was in the field of telegraphy and telephony. This utilizes a pair of wires.the start of wireless transmission for radio communication can be taken from the work of Henry's hertz, a German physicist in 1887,first of all he demonstrated the effect of electromagnetic radiation through space.with the development in this field it is not possible to transmit any message from one place to another thousands of kilometres away.
Industrial applications
The automatic control circuit are used in very early in the industries now a days. These are used to control quality, thickness off job, cutting of job, moisture content in material, lightning system, sound system and automatic door openers there are so many other operation in the industry which are automatically controlled by electronic circuits.
Defence applications
The communication system play an important role during the war days.the success or defect of a nation largely depend upon the reliability of its communication system. All the message are conveyed through a communication system.
Application in medical science
various electronic machine equipment are used by the doctor in diagnosis and treatment of various disease. Some of the machine equipment are given below.
- Electron microscope to analyse blood etc.
- X ray for taking pictures of bone structure.
- Electrocardiograph to study the condition of heart.
- Oscilloscope are used as the display to monitor the heartbeat of the patient.
- Short wave diathermy units for healing sprain and fracture etc.
Application in automobiles
More and more electronic equipment used in car for charging of battery, power assist function, measuring gauze and monitoring and control of engine performance. The most important application in automobile is electronic ignition, which provide better timing of the ignition spark, especially at high speeds.
Digital electronics
the circuit for digital application operate with pulses of voltage of current a pulse wave form is either completely on or off because of the sudden changes in amplitude. In between values have no function. All the digital clock counter calculators computer are operated by this pulses.
Si units
In French, si stand for system international d units and is the modern form of metric system.this system was finally agreed upon at the 11th international conference of weight and measure 1960.si system possesses feature that make it logically superior to any other system and also more convenient as it coherent rational and comprehensive.a system of unit is said to be coherent if the product or question of any two unit quantities in the system is the unit of the resultant quantity without the introduction of any numerical factors.
the international system of unit is based on seven base unit with the unit symbol assigned to each of them as given in the table,
This is dummy text. It is not meant to be read. Accordingly, it is difficult to figure out when to end it. But then, this is dummy text. It is not meant to be read. Period.
If you have any doubts. Please let me know ConversionConversion EmoticonEmoticon