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Sony J21MF1 - Picture is too dark

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New Member
Dear All my friends

I found a very old TV from my mom's place and when I looked it the flyback was blown up . So, I found the model number of the flyback and replaced the used one, just borrow it from my friend who repair TV it is - "811" . so it's working again. however, the brightness seems very low on this unit and I tried few settings on service mode and finally did a factory default on all settings. now the brightness seems even worse. when I check G2 voltage(1000v) around 900 and 200V seems 190 v of the CRT board seems low. I downloaded the diagram but I believe the flyback is not the correct one. Do you think is this issue with Flyback or other electronics

Please let me know your valuable answer.


Nigel Goodwin

Super Moderator
Most Helpful Member
Have you tried adjusting the G2 voltage?, usually with a pot built-in the transformer.

I would suspect that it may well just be that the CRT is worn out?.


New Member
Have you tried cleaning the glass screen with window cleaner yet?

Really... try cleaning the glass.

Aside from that it sounds like a low voltage issue, I'd check all of the capacitors that are in that circuit.
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