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NFG Forums => RGB + Video Discussions => Topic started by: vkp_ashley on February 18, 2008, 11:51:16 AM

Title: D for Dead pixel
Post by: vkp_ashley on February 18, 2008, 11:51:16 AM
OK here's the story. I finally bought a Commodore 1084 monitor, I opened it up to make adjustments to the h-size, v-size, colors and focus, my normal new old monitor procedure, and tested it out. My LM1881 is currently on the fritz right now, somethings wrong with it, but I was able to verify good RGB quality. I didn't notice anything wrong until I watched a DVD via S-Video. And BAM, it's right there!

(http://img134.imageshack.us/img134/2809/sheetary7.jpg)

There's a Black dot on sheeta's face. It's probably kinda hard to notice it from the picture, but it's there.

I know the monitor is about 20 years old, and that I should thank my lucky stars that this is the only dead pixel there is, but I'm just too nit-picky when it comes to overall picture quality.

I googled around to see if it's possible to give life back to dead pixels, but It seems that once they're dead, they stay dead, at least on CRTs anyway.

Oh well, better luck next monitor.
Title: Re: D for Dead pixel
Post by: blackevilweredragon on February 18, 2008, 01:09:58 PM
CRT's don't get dead pixels.

It's either 1 of 2 things.

1.  Defect in shadowmask during manufacturing.
2.  Burn.
Title: Re: D for Dead pixel
Post by: vkp_ashley on February 18, 2008, 03:02:17 PM
You know what, your right. It's either missing phosphor material or an obstruction in the shadow mask.

Thanks for pointing that out. Reading about how a CRT is built helps in understanding.
Title: Re: D for Dead pixel
Post by: Endymion on February 19, 2008, 01:55:45 AM
I have a 1084 that had the same deal, just appears to be a little dot somewhere in the screen. There's really not anything you can do except try not to look at it.
Title: Re: D for Dead pixel
Post by: l_oliveira on February 26, 2008, 01:18:46 AM
When you turn the thing off it shoots a strong beam into the center of the CRT and that's how the black dot is made.
I'm pretty sure there's a circuit to prevent it, but if some electrolythic capacitor in the said protection circuit is worn out it doesn't do it's job and the screen center get burnt.