sony problems


  #1  
Old 05-24-04, 06:52 PM
djhuff33
Visiting Guest
Posts: n/a
sony problems

I have a sony 27" Trinitron model kv-27s36. It was working fine. This morning I turned it on and the picture was scrunched on the top half of the screen. After a minute or two it went to full screen picture, then back to half screen. After two times of the the picture screen went black. Sound works and changes channels fine, just no picture.
 
  #2  
Old 05-24-04, 09:02 PM
jughead's Avatar
Member
Join Date: Oct 2003
Location: Davenport, Iowa
Posts: 597
Likes: 0
Received 0 Likes on 0 Posts
You didn't say if the screen went to half in the vertical or horizontal. Sounds more like the horizontal as you seem to have lost the picture (and HV) so it's time to look at the horizontal output or horizontal output driver transistor. One, or both, of them are probably shorted and will need to be replaced. At least that's the guess I'd make with the information that's been presented.
 
  #3  
Old 05-25-04, 03:33 PM
djhuff33
Visiting Guest
Posts: n/a
sorry, it went horizontal. Do you have any idea which ones control the horizontal?
 
  #4  
Old 05-26-04, 02:28 PM
jughead's Avatar
Member
Join Date: Oct 2003
Location: Davenport, Iowa
Posts: 597
Likes: 0
Received 0 Likes on 0 Posts
After rereading your orgional post I got the idea that the problems are vertical in nature. Sounds like the vertical output and/or driver transistors have shorted. That would most likely cause the picture to go out as well because the horizontal and high voltage supplies would go dead because of a short in the vertical section. Unless you are comfortable tearing your TV set apart and finding & replacing the output transistors it's time for a new TV set. Usually an older set isn't worth repairing because the cost of doing that is a significant percentage of the new cost, especially if you can't do it yourself.
 
  #5  
Old 05-27-04, 09:45 AM
D
Member
Join Date: May 2003
Posts: 134
Likes: 0
Received 0 Likes on 0 Posts
Non sense. This set doesn’t use vertical transistors. It uses an IC. This is a quick and cheap (no parts) repair. If you can solder, you can fix it. You can find help with specific instructions out there but the rules of the board prevents posting any web sites.

Dakota
 
  #6  
Old 05-27-04, 03:44 PM
djhuff33
Visiting Guest
Posts: n/a
I do some work on old computers, so soldering my not be that much trouble. The biggest trouble is which ones sre bad. I have puchased a new set already, but I would like to try to fix the set! Any advise would be great.
 
  #7  
Old 05-28-04, 01:36 AM
jughead's Avatar
Member
Join Date: Oct 2003
Location: Davenport, Iowa
Posts: 597
Likes: 0
Received 0 Likes on 0 Posts
The assumptions that the probem is easy to fix and is a "no parts" repair my be a bit optimistic. I'd like to have dakota's crystal ball. I didn't consult a service manual for the TV so the remark about the IC may, indeed, be correct. However ICs don't usually "just" go bad without other issues being involved. There could be additional power supply problems of perhaps a shorted deflection coil that caused the problem with the IC in the first place. If you wish to take a shot at fixing the set then open it up. You will probably find a small diagram pasted somewhere inside that will give you the location and fuction of the various ICs. You will have to remove the circuit board by disconnecting a lot of wires. The task will then be to locate the vertical deflection IC (assuming that it's the REAL cause of the problem), get the number, order the part, and replace it without tearing something else up. You can then put the TV back together and give it a try. If it still doesn't work you can repeat the process as often as necessary until you get tired of the whole thing, you get the set fixed, or you run out of money. Before you start the adventure I would invest in a SAMS photofacts manual first. That manual for your TV should still be available on the internet. All I can say is that I worked on my own Sony about a year ago and it was a royal pain because I don't have the shop or equipment anymore to deal with such things or maybe I'm just getting too old.
 
  #8  
Old 05-28-04, 05:40 AM
D
Member
Join Date: May 2003
Posts: 134
Likes: 0
Received 0 Likes on 0 Posts
My optimism is based on 28 years of working on Sony tvs. Plus you won't find any diagrams inside the set. Your problem is common and in most cases do not need any parts. We have helped many people fix their own tv. So you can decide for yourself.

Dakota
 
  #9  
Old 05-28-04, 07:26 AM
S
Banned. Rule And/Or Policy Violation
Join Date: Nov 2002
Location: Atlanta, Ga
Posts: 2,691
Likes: 0
Received 0 Likes on 0 Posts
Dakota, feel free to post a direct link to a manual or list in the post (not just a www.somesite.com, but a direct link please.)

I don't know enough about TV's to know who's right or wrong, but either way, let's make sure we keep it friendly - Thanks guys

Good luck, djhuff33!
 
  #10  
Old 06-17-04, 07:24 PM
djhuff33
Visiting Guest
Posts: n/a
Well I pulled the set apart last Friday. Boy do they get dusty! Carefully pulled the wire clips off and did a simple clean up. Didn't see anything bad. Put the set back together and it worked for about 6 days. It went out this morning-same problem as before. Any help out there?
 
  #11  
Old 06-19-04, 05:12 AM
jughead's Avatar
Member
Join Date: Oct 2003
Location: Davenport, Iowa
Posts: 597
Likes: 0
Received 0 Likes on 0 Posts
Sony TV's are known to have problems with cold solder joints. You might try removing the main circuit board and resoldering the joints in and around the horizontal deflection section. You might get lucky.
 
  #12  
Old 07-19-04, 07:22 PM
Kambiz_r
Visiting Guest
Posts: n/a
Question I have the same problem!

Did you get any luck with ur tv?
I have the same problem.
 
  #13  
Old 08-02-04, 11:17 PM
AricCougar
Visiting Guest
Posts: n/a
Exclamation Same Problem

Yes... I'm curious how it worked out. I just began having the same problem too, with a very similar (but expensive) Sony model. The sides occasionally (a few times an hour) flicker in, deforming the screen temporarily... much more so until it heats up, then much less. They bend in more at the top than bottom, and a bit more on the left side of the screen than the right. I was worried that this may have something more physical than electronic since i have placed the center channel speaker resting atop the tube for the last 7 years, and there IS a nearly noticeable bulge in the hard plastic on middle left side of the TV that i have not figured out its cause or source.

But it seems to be a vertical deflection problem -- at least the outward problematic result mirrors the descriptions above.

I'm a recently graduated Electronics Engineer with hundreds of lab hour-time, so i wish to fix it myself. Is it more appropriate to start a new link for my issue or continue it within this thread? Thanks.

- Aric
 

Last edited by AricCougar; 08-05-04 at 11:25 AM.
  #14  
Old 08-03-04, 01:38 PM
threesheds
Visiting Guest
Posts: n/a
Still discussing who's the cleverest and who has the best view of the trade eh! It was this that put a a polite bloke such as myself off posting a few months back. I found I was beginning to take part!
 
  #15  
Old 08-03-04, 06:10 PM
Kambiz_r
Visiting Guest
Posts: n/a
Red face I fixed it :D

I have resoldered all joints around Vertical and Horizontal transistors, and it's working perfectly now... thanks to jughead's tip.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: