I got a used 21" Dell UltraScan P1110 (Trinitron) yesterday, and the image on it was beautiful until I accidentally hit the factory default reset button. After that, the baseline brightness is very high; even at "zero" brightness, it's nowhere near the black point.
I've toyed with all of the OSD features (none of which seem to affect brightness) and researched this question, and it seems to me that most people's solution is some kind of electrical modification. But is that really necessary? Isn't there something I can do to turn its baseline brightness back down?
This monitor does not seem to have a 'service mode'; I've tried several different documented approaches to entering it, and none of them lead to a password propmt.
My motivation for this enterprise is that the brightness was correctly tuned before. Surely it must have gotten that way somehow? How do I get it back there?
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If I understand correctly, you're referring to the 'expert' colour temperature settings. I've fiddled all around with those, but all they seem to do is affect colour. Background brightness subsists at an absurdly high level. I'm quite certain the solution lies elsewhere.
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Try using the colour calibrate which you can only do after the unit has been on for 30 minutes.
if this does not work then try the following.
If you turn down all 3 backgrounds by equal amounts the the colour temperature should remain the same but reduce the brightness level.
If this does not solve your problem the only resort is too take it to a Sony repair agent and have them set it up on the DAS software.
Pressing restore has called up the factory settings, the reason it is now too bright is either the factory setting for brightness has been corrupted or the monitor had been set up by someone else using the expert mode to make the picture darker.
Rich
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Well, I've turned down the three RGB gains and that did have a slight downward effect on brightness, but nothing worth mentioning. It's still absurdly bright.
Surely there's got to be a way to sort this out without finding a Sony repair agent! The shop from which I got the monitor almost certainly did not have that done, and I doubt the original user of the monitor did either. It all seems very improbable.
Where does one find a Sony repair agent, anyhow? How does one look that sort of thing up? The Sony website leaves me utterly bewildered.
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Hi it is not the gains that need turning down, the gain is akin to the contrast for each colur where the backgrounds are the equivelent to the brightness for each colour.
Some where in the postings on this forum a guy called "Cid" says that this problem is usually caused by component failure in the G2 circuit but as the cost of monitors is now so low no one has delved that deep to find which component causes this problem.
Rich
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Yeah, I realise now that the biases is what I had turned down, not the gains. Thank you for that clarification nevertheless.
There has got to be an easier way to sort this out. When I got the monitor two days ago the brightness was at a perfect black point. It doesn't seem to me that circuit/component problems would permit that, but rather that they would foster a chronic, pervasive problem. It was fine prior to my hitting the settings reset button; I should be able to get it back to how it was before without making any electrical justifications.
I finally found a copy of the Dell DAS software and several variations on that theme, but unfortunately all of them require a HASP dongle.
There has got to be some way.
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I am happy to report that I have fixed my brightness problem on my Dell UltraScan P1110 (Sony Trinitron). I decided to go ahead and replace a resistor, as recommended ubiquitously online, and it worked. Essentially, I followed this procedure:
Basically, replacing the 10 meg resistor at junction R459 on the controller sorts the problem and gets low brightness back down to a suitable black level. Somewhat counterintuitively, the lower the resistance is, the lower the brightness (the circuit of which R459 is part provides positive feedback to some regulator, I think; it's not directly responsible for brightness).
That page recommends something in the 4.7 meg - 6.8 meg range, so we installed a 6.8 meg resistor. This is because my baseline brightness level wasn't really "too bright"; if it were superbright, a more radical solution (e.g. 4.7 meg) would have been in order. Also, the page does not mention it, but other sites mention that the resistors need to be rated for at least 0.5 W. This is crucial if you want to avoid it burning up. Radio Shack carries resistors in the 4.7 - 6.8 range, but only rated at 0.25 W, so I had to order some from DigiKey that fit the bill.
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Many thanks for your post. I'm having the same problem, so I thought I'd try your solution, but I don't know anything about electronics and soldering.
I'd like to order the same resistor you used from Digi-Key, but I don't know exactly what I'm looking for. Can you provide a link, or more detailed specifications?
Many thanks in advance for your advice.
Cheers,
Matt Stuehler
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I've soldered 5.1 MOhm resistor instead of 10 MOhm.
Now brightness level is pretty good, but there's another problem: EVERYTHIG BECAME VERY RED !!!
"Color Return" function didn't help.
I've lowered red bias to zero, but greys are still reddish.
Brightness controll affects only red brightness (when I increase brightness, picture becomes red, and when decrease - it becomes green-blue).
Help me, please, to fix this bug.
P.S. sorry for my bad english.
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