Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Solid State CRT Televisions

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #16  
Old 02-20-2016, 11:15 AM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
I finally ordered a kit off eBay today. I guess we'll see toward the end of next week how making these adjustments affects the convergence.
Reply With Quote
  #17  
Old 02-20-2016, 05:52 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Well, now I have a bigger incentive to get this thing adjusted properly, as my favorite CRT computer monitor, my Samsung Syncmaster 17GL, has just bitten the dust. The image on it went REALLY narrow and unstable today. I unhooked it, took it apart, re-soldered a couple of bad-looking joints on the flyback, and put it back together, but the situation only improved by the instability going away. The picture is much too narrow to be usable on it now. Unfortunately, though I've been able to find the schematics for the Samsung, they are VERY complex, and I'm having a hard time even finding which part of the circuit I think I should be looking at, so I think I'm just going to consider it a loss and focus on making this CompuAdd monitor looking as good as I can instead.
Reply With Quote
  #18  
Old 02-24-2016, 04:57 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Aw man, I got the alignment kit in, picked the closest fit, and tried to give that inductor at the back of the yoke a turn... It's cemented in place, so it's not going anywhere. In fact, the alignment tool (I had my pick of slightly too small or slightly too big) just started slipping around inside the inductor core after I applied a certain amount of force. I guess my last shot before trying to break the yoke free and move it actually would be re-capping this thing now.
Reply With Quote
  #19  
Old 02-27-2016, 11:18 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Actually, the more I use this, and the more I look at all the little distortions on the screen, the more I'm suspecting that the yoke has deformed, possibly due to heat or something. It's certainly still glued in place where the three wedges are, but that doesn't mean it hasn't warped in the spaces between them. I might still re-cap it, just to try to give it some extra longevity, but I don't think I can expect an electrical fix for the convergence issues.
Reply With Quote
  #20  
Old 02-28-2016, 11:53 AM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Hmm, I've found someone apparently selling a new CRT that matches the one in this monitor. I've e-mailed them to ask if the yoke is attached (they show a picture of a CRT with yoke attached, but have a note saying it may not represent the actual item). If it is, it may potentially solve two problems for me, one being the deformed yoke (if that actually is what's causing my convergence issues) and the other being the small abrasion on the face of the CRT. It's a pity it's as expensive as it is, but considering I've been looking up new-old-stock CRT monitors and most of them sell for about twice as much as this tube, I guess it's not too bad a deal.
Reply With Quote
Audiokarma
  #21  
Old 02-28-2016, 12:34 PM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 4,752
"may not represent the actual item"

Personally, I would not buy unless the seller provides a picture of the actual item, as well as verifying it's the right one.
__________________
www.bretl.com
Old TV literature, New York World's Fair, and other miscellany
Reply With Quote
  #22  
Old 02-28-2016, 02:14 PM
MRX37 MRX37 is offline
VideoKarma Member
 
Join Date: Aug 2005
Posts: 1,489
Another option if all else fails are believe it or not, pieces of refrigerator magnets taped to the corners of the CRT back. It takes some fiddling with size pieces and positioning but it can help.
Reply With Quote
  #23  
Old 02-28-2016, 02:51 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Quote:
Originally Posted by MRX37 View Post
Another option if all else fails are believe it or not, pieces of refrigerator magnets taped to the corners of the CRT back. It takes some fiddling with size pieces and positioning but it can help.
Yeah, I remember when I took apart the 32" Trinitron TV I had a few years ago I saw that it had magnets glued to the back of the CRT for that purpose. Usually that's only necessary on larger CRTs, though, which is what makes me think something more is wrong with this monitor.

I have a short strip of refrigerator magnet material that I tried positioning on the back of this CRT, but I didn't see any positive effects from it, at least not the way I was trying to use it.
Reply With Quote
  #24  
Old 02-28-2016, 04:09 PM
Chip Chester Chip Chester is offline
VideoKarma Member
 
Join Date: Apr 2012
Posts: 621
Have you made the rounds of your local tech buddies, recycling businesses, etc. to see if someone has a decent complete CRT monitor to just give away? It's likely only the better ones were kept around over the years...

Chip
Reply With Quote
  #25  
Old 02-28-2016, 04:11 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
No, but I want this one in particular because it's the same brand as the computer I'm using it with.
Reply With Quote
Audiokarma
  #26  
Old 02-29-2016, 12:24 AM
wkand wkand is offline
VideoKarma Member
 
Join Date: Oct 2005
Location: Everett WA
Posts: 248
CRT Monitor Convergence

Maybe someone mentioned it, but reading the entire thread, I did not see mention of any setup key or menus. I have never see a CRT monitor that relied entirely on internal adjustments for convergence, brightness, contrast, etc.
Reply With Quote
  #27  
Old 02-29-2016, 05:36 AM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Quote:
Originally Posted by wkand View Post
Maybe someone mentioned it, but reading the entire thread, I did not see mention of any setup key or menus. I have never see a CRT monitor that relied entirely on internal adjustments for convergence, brightness, contrast, etc.
This is a 1992 monitor, it's too old for that. All the screen size, position, pincushion, etc are all done with individual potentiometers.
Reply With Quote
  #28  
Old 03-01-2016, 08:01 AM
kf4rca kf4rca is offline
VideoKarma Member
 
Join Date: Feb 2015
Posts: 252
Samsung Syncmaster

I'd try to get your Syncmaster going if at all possible. The Syncmaster is like the Sony Multiscan which is like the NEC Multisync.
Unlike most monitors that are fixed frequency types the Syncmaster is a variable frequency type. It locks to whatever is given it.
If you ever get a Sun Microsystems computer, you will need the Syncmaster.
__________________
Reply With Quote
  #29  
Old 03-01-2016, 10:25 AM
andy's Avatar
andy andy is offline
VideoKarma Member
 
Join Date: Jul 2002
Location: Austin, TX
Posts: 3,996
Have you tried repositioning the yoke? 90% of the dynamic convergence is handled by tilting the front of the yoke. Sometimes the yoke gradually slides back and droops down over the years. The rubber wedges that hold the yoke in position can also move, or fall out. Check out the service manual to any TV with an in-line CRT for some idea of how to adjust the convergence.

Are you sure the CRT is original? One thing that will cause serious convergence problems is trying to use a CRT with an incompatible yoke. You'll end up with the red and blue rasters being either too big, or too small compared to the green.
__________________
Wanted list:
RCA CTC-5
RCA CTC19 or 27
Sony KV-7010U
Reply With Quote
  #30  
Old 03-01-2016, 04:58 PM
jmetal88 jmetal88 is offline
VideoKarma Member
 
Join Date: Jan 2008
Location: Derby, KS
Posts: 249
Quote:
Originally Posted by kf4rca View Post
I'd try to get your Syncmaster going if at all possible. The Syncmaster is like the Sony Multiscan which is like the NEC Multisync.
Unlike most monitors that are fixed frequency types the Syncmaster is a variable frequency type. It locks to whatever is given it.
If you ever get a Sun Microsystems computer, you will need the Syncmaster.
I already gave away the Syncmaster. I was NOT AT ALL interested in trying to troubleshoot the horizontal circuitry on that considering how complex it was.
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 01:04 AM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
ęCopyright 2012 VideoKarma.org, All rights reserved.