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Sony GDM-FW900 Monitor Brightness Problem

Hi All:

I was recently given a Sony GDM-FW900 widescreen monitor. It was in horrible condition as received. I went to great pains to clean up spilled beer and other vile stuff that was inside this monitor. To my suprise and delight, it actually powers up. However - There is a problem with it that I need help with . The screen is WAY over bright. Also, there are retrace ( term?) lines running diagonally down the screen about every two inches. It will display a windows desktop properly although out of focus a little bit. The additional brightness and lines are included with the desktop image. I would like to get this monitor running 100%. I can do some basic repairs myself, but will yield this job to a good tech if the required repair is highly specialized ( SM IC, reprogram, etc ). Can anybody help get me working in the right direction? Thanks for any replies.

Reply to
Bob Kos
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Is the Screen voltage set correctly?

Tom

Reply to
Tom MacIntyre

I don't know if the screen voltage is set correctly. I'm not familiar with that term. I presume that you are referring to the 'Focus' adjustments on the flyback? I carefully marked those and moved each a little to see if the condition got better or worsened. It didn't change much for better or worse, so I set them back where they were.

Reply to
Bob Kos

No, the screen is different, usually on the flyback, but I think on Sony monitors there is special software you need to use.

Tom

Reply to
Tom MacIntyre

Look here! Dani.

formatting link

There is a modification used on some Sony monitors, I have done it three times, with no problems. If your screen is too dark, then maybe your G2 is too low. try the "R459 fix"! Not sure if your model is the same. It's a 4 - 10 meg I think on the CRT board. You have to play around with the value, as the level of overall brightness varies. solder a 1 Megohm resistor piggyback on top of the one there sometimes works.

Reply to
ronoster

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Problem solved. I found a setting in the menu system called 'Image Restore'. This setting doesn't work until the monitor has been on & stabilized for a while. I selected this menu option and the monitor went to work. It corrected the overbright condition and retrace lines on its own!! The colors are very nice now! I'm happy!

Thanks to all who replied with help.

Reply to
Bob Kos

I've fixed countless large Sony monitors with that. Andy Cuffe

snipped-for-privacy@gmail.com

Reply to
Andy Cuffe

Any idea what the actual purpose of this menu selection is? The fact that it fixed my monitor is great, but I can't imagine a menu setting designed to compensate for screwed up components or anything like that. The manual is quiet regarding the use of this option. Any thoughts?

Reply to
Bob Kos

I believe it measures the CRT cathode current for each gun and adjusts them to the correct preset levels. It's similar to the AKB used in TVs, only it doesn't operate continuously. My only question is why the CRTs in these monitors get so much brighter with age.

The monitors made before they added the restore feature required either a DAS calibration, or a modification to reduce the G2 voltage. There are also a lot of 21" Sony monitors with a restore feature that doesn't work. Andy Cuffe

snipped-for-privacy@gmail.com

Reply to
Andy Cuffe

that

to

is

I'd like to try and find out more information as to how this feature should be PROPERLY used. If you know of any good sources of info, please send me in the right direction. I'll continue to Google on it.

Thanks again.

Reply to
Bob Kos

Did you try the manual? I'm pretty sure all it's supposed to do is compensate for aging of the CRT and electronics. It allows the monitor to maintain accurate color reproduction over its entire life. Monitors without this feature gradually lose proper gray scale tracking and the guns age unevenly.

Andy Cuffe

snipped-for-privacy@gmail.com

Reply to
Andy Cuffe

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