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Discussion Starter #1
hi what are a few of the most common symptoms of transformer problems? thanks for any help.
 

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The most common symptom in a Hitachi would be shutdown, which is far more likely to be something else. High voltage that is off or focus problems can be other symptoms. Bad flybacks are rather rare in Hitachi sets, however.

You would likely get more useful information if you were to post your model and symptoms, along with any troubleshooting you have done and why you might be suspecting a bad flyback.
 

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46f510 when first turned on the picture will flash very quickly between dim, bright. center will jump out of focus quickly then flash back. in service crossthatch, lines will be blurry then quickly jump up and down changing from blurry to sharp very quickly. slight static crackle from flyback, when displaying different dve test patterns, flyback lightly squeels at different pitches and volumes depending on what pattern is showing. you can feel static charge while getting near flyback. thanks icaillo
 

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Is the drive to the flyback varying? B+ stable? If it is then you might have a bad flyback. My first thought would be a bad cap or a bad solder joint. When a flybak fails it is usually not intermittent like this, but it is possible.

If the center only is changing in focus then it is not likely a flyback problem, but a deflection or dynamic focus problem. The flyback would affect focus over the whole picture, typically.
 

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46f510 while doing service convergence crossthatch, at first the center will be sharp and in focus, and the outsides will be blurry. as time goes on it the center will gradually become blurry as the edges get sharp. does this sound like dynamic focus transformer? when veiwing tv it will do the same thing. thanks for your help
 

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Discussion Starter #6
dynamic focus?

46f510 while doing service convergence crossthatch, at first the center will be sharp and in focus, and the outsides will be blurry. as time goes on it the center will gradually become blurry as the edges get sharp. does this sound like dynamic focus transformer? when veiwing tv it will do the same thing. thanks for your help
 

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Re: dynamic focus?

Sounds more like a cap if it is changing.
 

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Re: dynamic focus?

any cap around there or through experience are you led to common culprits. YOu must remove to test I believe. is radio shack quality sufficient. if so i will go ahead and swap them all out since i have to take them out anyways. thanks
 

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Re: dynamic focus?

There are too many possibilities in the power supply, dynaminc focus, and high voltage control. Some troubleshooting and study of the circuit designs would be needed to proceed.

Your threads were merged. Please do not start multiple threads to discuss the same problem.
 
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