View Full Version : Sony KV-3000R greyscale


freakaftr8
06-22-2010, 05:03 PM
Hey guys,
I should probably know this, but on my set I notice that when I first power it up and for about 3 to 5 minutes after powering the set I notice that the greyscale is a hint red. After the 5 minutes it looks neutral. I have seen this on some other sets as well before. Maybe I should probe the drives on the CRT and see if I get a slight voltage change during warm up? Or is it a CRT issue.

Note: I have already cleaned the screen and drive pots and aligned greyscale after about an hour of the set powered up.

Shawn

ChrisW6ATV
06-22-2010, 11:05 PM
Shawn-

Based on my experience with a lot of Sony CRTs, it is probably a less-than-perfect CRT, unless the set is super-sharp and bright as soon as you turn it on. Possibly, weak electrolytic caps might affect the color as well, especially if the CRT is nice and bright when first powered up. Do you have an ESR meter for checking caps?

freakaftr8
06-23-2010, 12:01 AM
Chris the CRT is sharp, a lil dim at first, but brightenes up ofer a period of 3 minutes or less. yes i have an ESR meter. Im figuring on checking more caps in the drive circuits if it seems to get worse. I don't use it much at all considering what a 820DB22 goes for these days and thats if I can even get my hands on a good CRT. The set is plenty easy on the eyes off as well as on.

Shawn

ChrisW6ATV
06-28-2010, 09:38 PM
Shawn-

If the CRT is brighter after 2-3 minutes than it is after 20 seconds, then it probably is getting a bit weak. Your plan to minimize use sounds like a good one. I don't think caps are going to be related to the color issue.

freakaftr8
06-28-2010, 11:57 PM
The odd thing is that there is still a stripe down the very left side of the raster that is darker than the rest of the raster. You can really see it on a black background.

zenithfan1
06-29-2010, 12:00 AM
Isn't that a cap going bad somewhere in the Horiz. section? I remember that being a cause for a dark left side but I could be wrong........

freakaftr8
06-29-2010, 12:16 AM
I replaced a cap on the CRT neck for the luminence. the smear and the dark left got better, the smear is gone, but it's still a hair dark. Im thinking that it is a cap still, when the crt is powered up, it looks like the contrast has been turned all the way down, 30 seconds it gets brighter, and after a few, if I had a black raster, it's usually reddish tinted, then it finally after like 5 minutes the red background starts to level out to a nice greyscale.