Jittering pixels on a CRT monitor - Page 1
Forum section: electronics / repair

author: rancer4
author_rank: Newbie
timestamp: December 18, 2020, 01:34:31 am
content: Around every winter, my desktop CRT I got a few years ago, would start jittering the pixels on the screen. It usually happened around the time the heat started kicking on,that and my monitor being in a kind of corner alone, building up heat more than usual. Everything would be fine tho if i cooled off my room by opening the window.Well this year about the same time, I was moving my monitor and I accidentally set it down too hard or something, and then when the heat kicked on like a day or two later, I started getting jittering pixels. But it was more than usual. I tried to cool off my room and pull the CRT back away from the wall, but it hasn't stopped the pixels from doing this. And for the past week or so, it's just been getting a little bit worse and worse it seems.It just looks like on the screen, like some of the pixels are going in and out, or even dodging side to side maybe, like sort of wavy. I took a microscope and got a video of the pixels up close.Does anybody know what I could maybe do to get this fixed or whats going on with it? i called a tv repair shop and they offered to re-cap it, then i looked that up and it is just the answer to solving 90% of the problems with them. I wondered tho really how the shop could figure out which caps i needed or if he could find a cap set for this monitor.this is an optiquest q115. 21 inch. i run at 1600x1280 @76hz. the monitor owner manual shows this monitor is build to perfectly handle that, thats how I figured out the refresh rate, whatever the math problem it is you do with the information it gives.I got this monitor off of a photograph shop. Also when I got the monitor, there was what appeared after closer inspection and sometimes for what reason I dont know, if its the colors showing, there seems to be like, what appears to be a water drop that slid down the screen. this line, will move side to side a bit as the colors change or scenes change on my computer screen. it doesnt change anything with a different videocard.Heres the videohttps://streamable.com/47xjjbanyone got any idea what could be doing these things? thats the magnifier against the screen, but not near the "water tear" thing, just over differtn spots, some are what looks like text jittering some other parts parts of the screen that seem to be looking good.Before I taek it to a repair shop for something that might not be able to get fixed or maybe something else, just so I can get an idea before i throw money at this. Id like to keep it because its a high enough of a resolution and refresh rate that I can use it. and the brightness is still good.thanks

author: RoGeorge
author_rank: Super Contributor
timestamp: December 18, 2020, 01:46:49 am
content: Replace all the electrolytic capacitors.It doesn't worth wasting the time to identify which ones are still good. Soon, most probably the still good ones will fail, too, so just replace ALL of them. Replacing is much easier then testing them, and they are very cheap, about a few bucks al together.

author: wilfred
author_rank: Super Contributor
timestamp: December 18, 2020, 01:51:21 am
content: I had something similar but not with a CRT monitor. If I flexed the cable a bit it would go away. But it would soon start again. I eventually tried a new cable and it solved the problem. I'd try swapping out the cable as a first quick check to at least eliminate it as a possibility. Maybe try another PC or video card if you have something at hand.

author: BrianHG
author_rank: Super Contributor
timestamp: December 18, 2020, 02:04:50 am
content: Quote from: rancer4 on December 18, 2020, 01:34:31 amIs this a wobbling of the image in the corners?Try a lower res mode at 90hz or 120hz, or the current mode @ 60hz and see if it disappears.If it does, you may have 60hz magnetic field injection through the yoke since high current power consumption of electric heating in your neighborhood or city can generate a massive magnetic field if you live close to a large outdoor transformer or power distribution cables/transformer station. I used to have this problem at my old residence where I lived a block away from high tension lines with a booster station 3 blocks away.This is a limitation of CRTs who don't have either adequate magnetic shielding.You choice is 75hz/100hz modes if you live in a 50hz mains nation, or 90hz/120hz if you live in a 60hz mains nation. 85Hz shouldn't wobble as much.

author: rancer4
author_rank: Newbie
timestamp: December 18, 2020, 02:31:53 am
content: thanks. I think I'll get the CRT to the repair man, he told me he could get it done in a week, and recap the whole thing for around 100 bucks. Ill try to get it out tomorrow, so that means i gotta lug one of these older, smaller crts out from under the house out. this thing compared to the gateway 19 inch i got under the house this thing weighs i would say 40-50 pounds while it weighs maybe 20 or 25 pounds. this tings gotta be at least 50-60 pounds. i was glad to got it.ive never had a jittering problem except when it was warm before, all summer it would be fine even. unless the room got real hot but if i was there id cool it down. I kind of knew something like this might come up. the jittering is just all over randomnly, up and down the screen everywhere all sides, anywhere. i was thinking the water streak might be the phosporus but, idk. maybe the recap will magically fix that too. thatd be pretty good.

author: RoGeorge
author_rank: Super Contributor
timestamp: December 18, 2020, 02:37:08 am
content: For $100 you can probably find to buy a perfectly working second hand CRT or LCD. If you go for an LCD TV with a monitor input instead of buying a PC monitor, you might find a brand new TV for $100.

author: BrianHG
author_rank: Super Contributor
timestamp: December 18, 2020, 03:10:34 am
content: Quote from: RoGeorge on December 18, 2020, 02:37:08 amThe color quality wont be the same. (So long as the re-capping doesn't mess something else up.)However, the 'optiquest q115' is an OK quality CRT, but I wouldn't expect the focus and convergence and color to match that of a top notch desktop CRT, but it the color itself should roast a 100$ LCD if the monitor hasn't been abused and the video card is that of the glory days when the quality of the analog RGB output was taken care of.I know I have yet to see any LCD come anywhere near my Mitsubishi Diamond Pro 2070SB, and I keep it in top shape and I am now sad that I sold 2 of the original 3 I had. I guess I need to wait for affordable 1000nit AMOLED desktop monitors which wont burn in pixels or dim/limit/protect the display contrast when everything has a 100% white display. I thought display tech would have already reached this point, but I am sadden that I have to wait now for micro-led and it's big $$$ before I can get desktop screens with unlimited true 4000nits with infinity:1 contrast on each pixel.

author: rancer4
author_rank: Newbie
timestamp: December 18, 2020, 03:32:57 am
content: it is a 980 ti video card with a internal ramdac.i just cant stand and when i first seen lcd i couldnt stand them, i can tell the ghosting from any lcd, after 3 days or so, i get a headache or a dull feeling looking at a led screen. i wouldnt even call lcds monitors, screens is a better technical term for it. monitors are meant to show moving pictures in a timing we wont get headaches from. i used a active adapter for digital to analog on one videocard and when i got the analog out videocard after, i could tell the difference in the pause, it was like a 2 year headache disappeared. the cheap one i had wasn't very "instant".I willlearn to invent crts before i use an lcd for a viewing screen on active picture im looking at. i dont think movie theatres would ever use anything but a light emitter to display movies on. if they did it wouldnt look too good