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TV start up - need explanation, diagram of what starts TV

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rascabuche

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tv start up

can someone tell me how a tv start up after pushing the power buttyon on?can someone illustrate to me with a little digram where the voltages go to stary up the television. I know it has a flyback transformer, but i dont know if that starts the tv.

Thanks,

Rasc
 

Re: tv start up

Most of color TVs has Switch Mode power supplies built in. When the power switch is on this will power up the basic circuitry. Then the fly back starts to function and generate high voltages(EHT) to power up the TV tube. Then you see pictures on it.
 

Re: tv start up

A summarized version: (especially how image production is started after mains is connected through a power transistor & relay)

Here's the trick: When you switch on your set, a startup circuit pulses the horizontal oscillator. The startup circuit is like a defibrillator for a robot. In this case, the "robot" is the horizontal oscillator. The startup pulse pulses provides him with temporary power until his oscillations become self-sustaining.

Without a startup pulse, the horizontal oscillator is dead. Also, without horizontal oscillations, the horizontal output transistor can't provide drive current to the flyback. Of course, a flyback without drive means no power from scan-derived power supplies. Plain and simple: In a normal set, the startup pulse wakes up the entire circuit. In a moment, you have a picture.

Source: http://www.hawestv.com/mtv_FAQ/colrtelHowWksFAQ.htm
 

    rascabuche

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Re: tv start up

friends,
Thanks for the info.

Rasc
 

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