# picture distortion on an older CRT TV **URL:** \ **Category:** Factual Questions\ **Created:** [March 12, 2012, 1:26am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507 "2012-03-12T01:26:28Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [March 12, 2012, 1:26am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507/1 "2012-03-12T01:26:28Z")
and older (standard def) CRT TV we have started having some sort of distortion in its picture not too long ago. It sort of looks like the interlaced fields aren’t “aligned” properly anymore, but the jagged edges seem like they’d be wider than a scanline. Here’s a photo of the condition: [http://home.comcast.net/~jz78817/stuff/crt.jpg](http://home.comcast.net/~jz78817/stuff/crt.jpg) any idea what’s going wonky? ---
**Author:** ![eldowan](https://avatars.discourse-cdn.com/v4/letter/e/848f3c/32.png) [@eldowan](https://boards.straightdope.com/u/eldowan)\ **Post date:** [March 12, 2012, 1:37am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507/2 "2012-03-12T01:37:44Z")
Agreed on the scanline point. Is the distortion across the entire screen? On display signal only, or does it include the OSD as well? Volume boxes? It’s kinda hard to tell in detail on my phone, ATM. It sorta looks like its not affecting the OSD as much, so i wonder if its the signal decoding. If the OSD is good, then i would rule out the raygun and phosphorus coating on the screen. Is there color distortion as well? Is it more prevelant on still/static images or in full motion? Have you tried degauss by chance? ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [March 12, 2012, 1:42am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507/3 "2012-03-12T01:42:33Z")
My first thought would be the source is messed up. Is this standard def cable? How does the signal get from the box to the TV? Can you try a different source? ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [March 12, 2012, 1:45am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507/4 "2012-03-12T01:45:11Z")
> [@eldowan](#): > > Agreed on the scanline point. > > Is the distortion across the entire screen? On display signal only, or does it include the OSD as well? Volume boxes? It’s kinda hard to tell in detail on my phone, ATM. > > It sorta looks like its not affecting the OSD as much, so i wonder if its the signal decoding. If the OSD is good, then i would rule out the raygun and phosphorus coating on the screen. > > Is there color distortion as well? Is it more prevelant on still/static images or in full motion? > Have you tried degauss by chance? it was hard to get a good photo, but it happens all over the screen, and OSD is affected too. the blue box I centered on is the OSD. Color seems OK. it’s most noticeable on the OSD and on-screen text because of the sharp color transitions. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [March 12, 2012, 2:00am UTC](https://boards.straightdope.com/t/picture-distortion-on-an-older-crt-tv/615507/5 "2012-03-12T02:00:58Z")
Probably the [sync separator](http://en.wikipedia.org/wiki/Analog_television#Sync_Separator)circuit is messed up. Not worth trying to fix it.