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Revlac

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Joined: 31/12/2016
Location: Australia
Posts: 1128

Posted: 10:02am 02 Jun 2024

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This TV has been running great for a long time, until a day ago when the picture went notably dark, could still see it but its a bit of a strain on the eyes to keep watching, messing around with brightness and colour settings made no difference.

Time to open it up, see whats going on, I realise most people would probably throw it away and buy another, I would rather not add to the E-Waste pile without at least trying something.

The guts of it, well there isn't that much these days, powered it on and could see a dull glow in the plastic lugs on the back of the display and around the back light wires red and white, tested the voltage on the terminal with the red and white wires plugged in on standby it was about 10v, turned the display on and the voltage was about 20v Turned the TV off, removed the connector and turned the TV on again and measured the voltage at the pins, 63v and falling, plugged the back light in again and a bright flash from the back light then dull again.

Ok the power supply is unstable, WHY? those 2 capacitors 35v 330uF look stuffed, lets fix that with a replacement....well thought I had some but not easy to find the exact ones, so found 35v 470uF and a 35v 220uF not exact but worth a try, so put them in.

Plugged the power back in and turned the TV on, the back light was full brightness again.....Good.
There are some other parts on the circuit board that have been a bit hot but probably ok for a bit longer.

So its working again don't know for how long until some other part of it sh$ts itself, still it was worth the small effort and time spent fixing it.

Thought this might help someone out there.

Cheers Aaron
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Ziki_the
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Joined: 13/04/2023
Location: Yugoslavia
Posts: 39

Posted: 08:02pm 02 Jun 2024

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Great job..
If it is still open then, you can decrease current for led's by 25-30%.
Removing some of current resistors or change divider. Depends of driver for led.
If it's closed then just enjoy.

Pozdrav iz Srbije

Revlac

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Joined: 31/12/2016
Location: Australia
Posts: 1128

Posted: 11:15am 03 Jun 2024

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Hi, thanks I might have a look next time I have it apart, at the moment it is closed so will enjoy it.

Cheers Aaron
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