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No picture on my Dell 790 monitor (17

The monitor picture and Eht died. Only the green led still on the front.
Tube heaters still on and I can get a picture for about 3 minutes from absolutely cold then EHT dies and will not come back with turning set on/off. Picture returns for 3 minutes when switched back on a couple of days later. I have no schematic for this model.
Any help will be appreciated. Tom.

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  • TOMBLOKE Oct 28, 2008

    Hi guys, thanks for the response to my email regarding the Dell 790 17" monitor. I would have understood that my description that the eht had dissapeared, tube heaters still on and indeed the model number, would have been enough to indicate that it was a shadow mask tube not an LCD display. Your 'help' comments to me indicated that you understood the display to be an LCD.

    I am an electronics engineer but do not have a schematic for this model. I was hoping that some experienced person who was familiar with this model may have seen this fault and could steer me in the right direction. If you could email me the schematic I would be very greatful.

    Regards, Tom.

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Tom,
What you've got it a busted backlight inverter... need to replaced a new one or repaired it. To repaired, if you are lucky just replaced a couple of faulty capacitors in the power supply w/ built-in inverter... Good lucks, have nice day!

Posted on Oct 23, 2008

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