Rear projection TV repair.

[Philster]

I have a Hitachi rear 61" rear projection HDTV that is seven years old. It looks like one of the convergence output IC's is defective.

Thompson Electronics on E. Main St. is the factory service center. Has anyone had any experience with them?

I have them comming out Wednesday to repair the TV.

[festivus]

Hey, how did this go? I'm having a convergence issue at the bottom and the top corners of my screen on my philips. I just sent a repair request to Thompson.

I did some digging online to see if I could fix this myself but it looks to be beyond me. Still, I don't want to spend a ton of money to repair a set that I bought in 2002 or 2003.

[Philster]

They replaced the bad output IC with a newer version. He also replaced the other one which was still working just in case it was near the end of life. Cheaper than making a second trip later. He cleaned the lenses and re-aligned the converganve. I was very satisfied with the work he did. I cost me $397.00 and the picture looks great. Cheaper than a new TV.

[festivus]

My set has adjustments for red and blue convergence. None for green. Green looks to be the problem. I can adjust the red and blue to align with green. I finally figured out how to do that. I have to keep tapping my remote buttons instead of holding them down. Makes the color great but the picture bends at the bottom middle and top corners.

For $397, I may just live with the slight bending for a while. But thanks for letting me know what they typically charge.

[snodgrass23]

My set has adjustments for red and blue convergence. None for green. Green looks to be the problem. I can adjust the red and blue to align with green. I finally figured out how to do that. I have to keep tapping my remote buttons instead of holding them down. Makes the color great but the picture bends at the bottom middle and top corners.

For $397, I may just live with the slight bending for a while. But thanks for letting me know what they typically charge.

Green is generally used as the "central" color. It is "aimed" at the center, physically with a CRT setup, and the other two colors are aligned to it. A lot of the time, any controls for the green is hidden in the service menus so that users don't accidentally mess up this "baseline color". There should also be adjustments in the service menu to fix the "bowing" (used to be call pincushion adjustments on old CRT units, not sure if it still is).

[festivus]

Thanks, snodgrass. I found a post on another forum advising how I can get to this service menu. I'll probably see what I can do tonight.

[festivus]

Update: I got in the service menu and had an option under convergence to set to factory defaults. I figured why not do that? I did it and the picture looks perfect. I don't know how long it will last but it sure looks good now.

Well, the convergence wasn't quite right and I had to go in to the user menu to adjust the multipoint convergence. After doing that it looks really good. And as of this morning it still looked pretty good. Fingers crossed...

[festivus]

My convergence is off again and I can't get the green back to where it should be. I found a convergence board online for $80-$85. And I found some instructions for doing the work.

Anyone else ever do this? From what I've read, the most difficult part is labeling all of the connections so they can be correctly reattached to the new board.

Also, and I'll show that I'm not an electrical engineer here, does a typical convergence board contain ALL of the necessary ICs, resistors, etc.?

[snodgrass23]

I would think it would be a plug and play. I've switched boards (and tubes) on my front projection CRT and it looks scarier than it is. Just take your time and you should be fine.

[festivus]

Thanks. I've been reading that one must be careful to get the correct board. Both in terms of the one for your model and the correct board (convergence vs other). I'll probably find a dealer that I can call to make that I get the right one.

[snodgrass23]

Assuming you know what board to pull, it should have a part number stamped on the circuit board. It will likely only fit in one spot as well.

[festivus]

You sound like you know a lot about this, snodgrass. So, can you check out this link and let me know which of these parts is the convergence board? I don't want to tear apart the set until I have the new part and am ready to fix it. Thanks again.

http://www.encompassparts.com/models/?NAP55PP9502

I was going to guess this one but I wanted to be sure.

313503710081 *HDR* CRT BD

[snodgrass23]

Hard to say for sure since I'm not familiar with that model. I looked up some info on that part number (313503710081) and it looks like that is the driver board for the tubes. There would be one attached to the back of each of your tubes. I'm not sure if that would affect your convergence, though. It would likely show up in a tube not working very well or at all, though I guess it's possible it could affect the geometry of the output of the affected tube.

[festivus]

Thanks for your help. Seems that this might be more difficult than I first thought, at least for a novice like me. A repair guy on another forum wrote that he never replaces philips boards because of the difficulty in getting the correct one. He'll repair the board instead replacing ICs and/or resistors. I don't have soldering and testing equipment so I didn't want to go that route even though there is a lot of good instructional material online.

I think I'll stick it out until this TV gets so bad that it's unwatchable. Then it will be time for an LCD or Plasma. Thanks again.

[festivus]

Well, my TV has held up pretty well but now it's getting really bad. A couple of days ago the green was way off and flickering badly. Funny thing is that it improved last night and became somewhat watchable, after warming up for a few hours.

Since it looks like the repair might be more than I can handle myself and will cost too much for a pro to do it I may be looking to unload the set and upgrade to an LCD or Plasma. Even though I don't really have the money right now.

Does anyone know of the best way to get rid of a set that simply needs a little bit of repair work? Any local shops buy them? I was thinking of running a pickup-only ebay ad. Thoughts?