[Gadzie]

Ok, first of all, I would like to thank all the supporters of this forum and contributers. Without you folks, I would still be banging away at google for answers.

Convergence issue is fixed thanks to 2, STK394-160 IC's and 6 new 1.8 ohm 1w resistors from NTE. Thanks to HBF Electronics for their help. (Also, their online ordering system isn't secure and as a computer professional, I wouldn't advise using this method to order parts from anyone like this)

To the new problem and probably present when I started this project as it was on the side of the road with a "Free" sign attached to it.

PS3 attached to the TV with Component cables, 1080i works with minor glitching at the top half of the set. Small lines on the left and right about an inch wide and a small amount of flickering on the entire top half of the screen. 720p will not work properly and nor will 480p. The entire screen appears out of sync. Tested ANT 1 and ANT 2 inputs and I get the same result. As lcaillo suggested, I did go over the signal/conv board to the best of my ability. I saw some normal wear and tear on the board or so it appeared. The board itself has 3 other boards that do directly connect to it.

Now, like I said, this problem is something I remember from before I started this repair and im pretty sure I didn't cause this. If anyone can help, I would appreciate it. I can provide pics and also have the repair manual for this model.

Gadz

 

[lcaillo]

It sounds like a very common problem on the hyper module. Change all of the 10uF and 22uF surface mount polar electrolytics, resolder the oscillators, and test all of the remaining polar electrolytic caps for ESR.

 

[Gadzie]

Ok, so after some research and head banging.. The hyper module I have in this model tv doesn't appear to belong in this tv.. The specs in the manual call for a PD0264A and the board I pulled out has a (C) written above the PD0264 along with a (C) written to the left of the connector. MVPU13 is what is showing on top of the unit itself.

What now?

 

[lcaillo]

Had it ben changed before? The difference is likely not significant. It could have been a production change or the module may have been rebuilt already.

 

[Gadzie]

So, after some searching on the net, I found a guy about an hour away that had a 50hx81 he want to get rid of. I decided that the differences between the models weren't significant enough to not warrant going and getting this tv. The TV powers on and the red light stays solid but, no video at all. I found after leaving it on for a bit, it actually shut itself off. Now, the covergence IC's I had put in the first TV, I took out and put them in the 50hx81 and I tested all the resistors and fuses. I checked for burn marks or any obvious signs for damage. When the set comes on, the tubes have a dim orange glow. I have parts to swap between the units to get atleast one running now. So, any suggestions on where to go from here?

The unit doesn't display anything, menu included. The unit does have audio coming out.

 

[lcaillo]

Where to go from here is basic troubleshooting. There are many things to check, starting with the power supplies, sweep circuits, and high voltage. Most common in these is likely bad solder connections in the vertical output circuit or a bad vertical output IC. That is just a guess, however. As you have learned, not every problem is a matter of changing convergence chips. Before changing parts, it is advisable to be sure that you know what the problem actually is. Step by step troubleshooting is beyond the scope of this forum. If you would like to learn more about TV repair in general, look to the vast amount of information in the sci.electronics.repair FAQ by Sam Goldwasser.

 

[Gadzie]

Thanks. Based on the extent of convergence IC's that need replacing, I made the initiative to do so, since the part I had was superior to the stk392-110 that was installed in the unit to begin with. I'll do more research and post my findings. Always good to know someone is willing to point you in the right direction.

 

[Gadzie]

You know, I started reading and some of the parts as they are described reminds of a line from "Spaceballs". The sweeps, the creeps, and the bleeps."

Are their any other books or sites that you might recommend? I am always interested in furthering my knowledge into electronics.

 

[lcaillo]

http://www.hometheatershack.com/for...ps-service-manuals-assorted-useful-links.html

 

[Gadzie]

Thanks, I'll make sure I dig a bit deeper into these forums before asking questions like that again.

 

[lcaillo]

If you find some good resources that are not included in my links please let me know. There are many, and what I have listed is just a tiny sampling of what is out there.

 

[Gadzie]

I found the schematics for this particular model. I'm reposting this http://www.schematicsforfree.com/ for anyone that is looking for the Service Manual, Owners Manual, or Schematics for the 50H81 or 50HX81.

 

[mikey219]

So, after some searching on the net, I found a guy about an hour away that had a 50hx81 he want to get rid of. I decided that the differences between the models weren't significant enough to not warrant going and getting this tv. The TV powers on and the red light stays solid but, no video at all. I found after leaving it on for a bit, it actually shut itself off. Now, the covergence IC's I had put in the first TV, I took out and put them in the 50hx81 and I tested all the resistors and fuses. I checked for burn marks or any obvious signs for damage. When the set comes on, the tubes have a dim orange glow. I have parts to swap between the units to get atleast one running now. So, any suggestions on where to go from here?

The unit doesn't display anything, menu included. The unit does have audio coming out.

For what its worth: I tried to repair my hyperboard myself and screwed it up. After reinstalling it I had the same symptons that you described above. Remove that hyperboard from the signal board then see if you get anything on the screen. If you do, you're hyperboard is bad. Good luck!

 

[Gadzie]

Thanks Mikey for the info. Since I had 2 units that were very similiar, I took the first hyper board from the unit that was displaying video, but had signal issues and put it in the unit that no video and found that it in fact was the problem. I wonder why a third party hasn't started manufacturing these boards again.. They could make some money.. With some reference material on the net, I am going to attempt the repair myself and I will let you know how it goes. There are some very informative videos on Surface mount soldering on Youtube and they also go over desoldering these types of things as well.

 

[lcaillo]

PTS has rebuilt these boards for years. It is unlikely that anyone could make a profit making new ones. The cost would be too high and the variations in different models would require too many different versions.

Most of the hyper boards can be fixed by replacing the 10uF and 22uF polar electrolytic capacitors. Some require more caps to be replaced (recommend ESR testing all of them), some boards need the oscillators resoldered, and some have problems in other components that are not practical to troubleshoot and repair.

 

[mikey219]

Thanks Mikey for the info. Since I had 2 units that were very similiar, I took the first hyper board from the unit that was displaying video, but had signal issues and put it in the unit that no video and found that it in fact was the problem. I wonder why a third party hasn't started manufacturing these boards again.. They could make some money.. With some reference material on the net, I am going to attempt the repair myself and I will let you know how it goes. There are some very informative videos on Surface mount soldering on Youtube and they also go over desoldering these types of things as well.

Gadzie, please be extra careful working on those caps. I've been soldering for years and I had a hell of a time. Bad eyesight and the shakes. I lifted three traces off. If I had to do it over I would just send my board to Ken on ebay and let him do it for $75. (do a search on ebay for hyperboard ).I believe he changes every cap on that board. Here are a couple of links to a discussion about this topic. Good luck!
http://www.techlore.com/forum/thread/15237/Toshiba--Model4283--picture-is-zig-zag./?page=3
http://www.dshosu.com/how-to-fix-toshiba-rear-projection-hdtv-wavy-lines/

 

[lcaillo]

Lots of techs just cut the caps off with a pair of diagonal cutters then remove the leads. This keeps you from stressing the traces.

I prefer to add some fresh solder which helps to loosen the joints.

 

[mikey219]

Lots of techs just cut the caps off with a pair of diagonal cutters then remove the leads. This keeps you from stressing the traces.

I prefer to add some fresh solder which helps to loosen the joints.

Thats a great suggestion. wish I would of thought of that!

 

[Gadzie]

UPDATE..

Ok, so, I had Ken fix the boards and 1 hyper module displays 1080i properly and not 480i or 480p and intermittently the other inputs work properly. The other does all 3 confidently (component input).. but through the other inputs the screen appears scrambled.. Based on what I have read on Hyper module issues, it appears as though they weren't fixed properly.. Any opinions?

 

[mikey219]

UPDATE..

Ok, so, I had Ken fix the boards and 1 hyper module displays 1080i properly and not 480i or 480p and intermittently the other inputs work properly. The other does all 3 confidently (component input).. but through the other inputs the screen appears scrambled.. Based on what I have read on Hyper module issues, it appears as though they weren't fixed properly.. Any opinions?

Gadzie, Your description above is very hard to read and understand. I find it hard to believe that Ken didn't "fix" it properly. He just replaced all the caps. It sounds like you have other issues. Just go over your
circuit boards again and make sure you have everything plugged back in properly. If that don't work ,If you re-write your above description of your problem in a clearer and orderly fashion maybe Icaillo can point you in a better direction. Good luck!