23-06-2012, 06:02 PM
ELECTRONICS
INTRO_TO_ELECTRONICS.PPT (Size: 99 KB / Downloads: 56)
HISTORY OF ELECTRONICS
IT CAN BE SAID THAT ELECTRONICS TOOK BIRTH IN 1897, WHEN A VACUUM DIODE WAS DEVELOPED BY J.A.FLEMING.
HOWEVER THE REAL BEGINNING WAS MADE IN 1906, WHEN LEE DE FOREST DEVELOPED THE VACUUM TRIODE.
WITHOUT THIS DEVICE, THE AMPLIFIERS i.e. THE HEART OF ALL ELECTRONICS GADJETS, WOULD NOT HAVE BEEN MADE POSSIBLE.
THE VACUUM TUBE DEVICES DOMINATED THE FIELD OF ELECTRONICS UNTIL THE END OF WORLD WAR II.
APPLICATIONS OF ELECTRONICS:
THE ELECTRONICS PLAYS AN IMPORTANT ROLE IN ALMOST EVERY SPHERE OF OUR LIFE.
IT HAS PENETRATED IN EVERY FIELD e.g. FROM AN ORDINARY WRIST WATCH TO SUPER COMPUTERS; FROM TELEPHONE REPEATERS BURIED DEEP UNDER SEA TO SPACESHIPS FAR OUT IN SPACE; FROM THE CONTROL OF MODERN HOUSEHOLD APPLIANCES TO THE CONTROL OF 400000 TONNE SUPERTANKER CARRYING CARGO ACROSS THE SEA.
COMMUNICATIONS AND ENTERTAINMENTS:
IN EARLIER STAGES, THE MAIN APPLICATION OF ELECTRONICS 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 HEINRICH HERTZ, A GERAMN PHYSICIST.
IN 1887, FIRST OF ALL, HE DEMONSTRATED THE EFFECT OF ELECTROMAGNETIC RADIATIONS THROUGH SPACE.
DEFENCE APPLICATIONS:
THE COMMUNICATION SYSTEM PLAYS AN IMPORTANT ROLE DURING THE WAR DAYS. THE SUCCESS OR DEFEAT OF A NATION LARGELY DEPENDS UPON THE RELIABILITY OF ITS COMMUNICATION SYSTEM. ALL THE MESSAGES ARE CONVEYED THROUGH COMMUNICATION SYSTEM.
THE OTHER IMPORTANT ELECTRONIC EQUIPMENT, USED DURING THE WAR DAYS IS RADAR(RADIO DETECTION AND RANGING).