10 amazing facts you might not know about television

Written by Irene Revallio

Byrepparttar timerepparttar 142148 typical U.S. youth has reached eighteen years of age they would have spent about 25000 hours watching tv. This means they would have actually spent more time watching televison than learning at school. The 1st colour television transmission occurred in John Logie Bairds English studio back in 1928.This transmission showed some blue and red scarves and a UK policeman's hat. Also shown was a mixed bunch of flowers, a guy poking his tongue out andrepparttar 142149 smouldering end of a cigarette. The first ever TV advert in history lasted twenty seconds and was for a clock manufactured by a corporation called Bulova. This company also manufacturedrepparttar 142150 1st timepiece that went into space. The commercial was seen in July 1941 and went out during a game being played byrepparttar 142151 Brooklyn Dodgers andrepparttar 142152 Philadelphia Phillies. The famous revolving globe that is utilized byrepparttar 142153 NBC news series spent many years turning inrepparttar 142154 wrong direction. In 1984 this was eventually found and on January 2nd this was put right and nowrepparttar 142155 globe is turning correctly. Way back in 1950 only 10 percent of U.S. households had a television in their possession. By 1960 this had changed to an unbeleivable 90 percent whilst today it is 99 percent with fifty four percent of U.S youngsters having one in their bedroom. Now more of us have tv's than we do a phone. The highest ever fee given to do a television advertisement was $2,000,000 per thirty seconds of time. This was paid by advertisers to run their adds duringrepparttar 142156 very last American screening ofrepparttar 142157 popular comedy series friends. The show was aired by American TV company NBC on May 6 2004 and lasted for a whole hour.

Testing Flyback Transformer-How to test and when to replace it

Written by Jestine Yong

Nowadays, more and more monitor comes in with flyback transformers problems. Testing flyback transformers are not difficult if you carefully followrepparttar instruction. In many cases,repparttar 141800 flyback transformer can become short circuit after using not more than 2 years. This is partly due to bad design and low quality materials used during manufactures flyback transformer. The question is what kind of problems can be found in a flyback transformer and how to test and when to replace it. Here is an explanation that will help you to identify many flyback transformer problems. There are nine common problems can be found in a flyback transformer. a) A shorted turned inrepparttar 141801 primary winding. b) An open or shorted internal capacitor in secondary section. c) Flyback Transformer becomes bulged or cracked. d) External arcing to ground. e) Internal arcing between windings. f) Shorted internal high voltage diode in secondary winding. g) Breakdown in focus / screen voltage divider causing blur display. h) Flyback Transformer breakdown at full operating voltage (breakdown when under load). i) Short circuit between primary and secondary winding.

Testing flyback transformer will be base on (a) and (b) since problem (c) is visible while problem (d) and (e) can be detected by hearingrepparttar 141802 arcing sound generated byrepparttar 141803 flyback transformer. Problem (f) can be checked with multimeter set torepparttar 141804 highest range measured from anode to ABL pin while (g) can be solved by adding a new monitor blur buster (For 14' & 15' monitor only.) Problem (h) can only be tested by substituting a known good similar Flyback Transformer. Different monitor have different type of flyback transformer design. Problem (i) can be checked using an ohm meter measuring between primary and secondary winding. A shorted turned or open in secondary winding is very uncommon.

What type of symptoms will appear if there is a shorted turned in primary winding? a) No display (No high voltage). b) Power blink. c) B+ voltage drop. d) Horizontal output transistor will get very hot and later become shorted. e) Along B+ line components will spoilt. Example:- secondary diode UF5404 and B+ FET IRF630. f) Sometimes it will causerepparttar 141805 power section to blow.

What type of symptoms will appear if a capacitor is open or shorted in a flyback transformer?

Capacitor shorted

a. No display (No high voltage). b. B+ voltage drop. c. Secondary diode (UF5404) will burned or shorted. d. Horizontal output transistor will get shorted. e. Power blink. f. Sometimes power section will blow, for example: Raffles 15 inch monitor. g. Power section shut down for example: Compaq V55, Samtron 4bi monitor. h. Sometimesrepparttar 141806 automatic brightness limiter (ABL) circuitry components will get burned. This circuit is usually located besiderepparttar 141807 flyback transformer. For example: LG520si

Capacitor open

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