Vintage RCA Projector Big Screen

[JohnCT]

Originally Posted by stushug

I had a service guy come over this morning, charged me $50 to tell me it's not worth fixing. That was all I needed to hear. I re-started from scratch and re-did the whole process until I got the grid almost perfect. Now I have the picture centered horizontally and vertically. The problem now is that the left side of the screen is perfect but on the right side I can see red and blue bleeding off to the right. It gets worse as you look from the middle to the right side. From the middle to the left side I can't see any of the red and blue bleeding. The bleeding doesn't seem to show on the grid, though.

Can you take a photo of the convergence board?

Also, take a pic of the screen grid with the blue lens covered up. We'll work on the red first. I want to see if that TV has right side specific adjustments as well as global adjustments or only global width and linearity. I wish now I hadn't pitched that service manual.

John

EDIT: was the guy who charged you $50 an old timer, or a flat screen board jockey? I can converge that TV in 10 minutes as could most guys who lived those years in the trade.

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[stushug]

He was an old timer, he told me on the phone he is 77. That's the only reason I took a chance on having him come look at it. As soon as he got there I could tell he didn't have any intention of doing anything that might be involved. He tried to tell me that my convergence board was bad because one of the transistors was hotter than the others.

[stushug]

Here's a picture of the board, I circled the transistor that he claimed was the problem. I also attached a pic of the grid before I got it pretty well aligned.

[stushug]

Here's the grid with blue lens covered, and the convergence setup page from the manual. It's not that clear, I hope you can see how the red drifts off in the bottom right corner. I can't upload the manual, it's twice the size of the allowed size, but I could email it to you.

[JohnCT]

Originally Posted by stushug

Here's the grid with blue lens covered, and the convergence setup page from the manual. It's not that clear, I hope you can see how the red drifts off in the bottom right corner. I can't upload the manual, it's twice the size of the allowed size, but I could email it to you.

First, those transistors do run at different temperatures. The drivers for the green run cooler than the others because there is less inherent error to correct.

I would take a close look at the bottom of all the transistors on heat sinks and check for uncracked solder. If there is some, a bit of liquid flux and heat will reflow them nicely.

If your blue convergence shows similar convergence to the red, you're very close (and better than the old timer..)

This board has limited adjustments, so you won't get perfection out of it. A lot of boards of that era have twice the adjustments, so it's possible to get a really good convergence even at the far corners.

With regards to the red, see if there is a red horiz bow adjustment. If there is, adjust it so the red fringe is the same distance away from the green from top to bottom. After that, adjust the red horiz width and linearity to pull the red in. If it doesn't have red horiz bow, just adjust the red horiz lin and red horiz width to tuck in the red in the middle. The top and bottom corners won't be perfect, but it's the best we can do with what adjustments we have.

Can you take a pic of the controls or send just the part of the manual that shows the conv board? Email is delstv@aol.com

John

[stushug]

On the convergence board, the upper row of controls adjusts the R/B at the same time and the lower row adjusts the green. My biggest concern was that the left side of the grid is almost perfect but from the middle vertical line to the right side the grid gets progressively worse with the lower right corner being off the most. It doesn't show well in the pic, but the blue is also off, though not as much as the red. During my bad day off moving every adjustment I could find, (a lesson learned,) I also moved each lens in and out, which changes the overall size of each color. I think the red and blue may be slightly larger than the green, causing those last few vertical lines to end up just outside the green lines they should land on. Does that make any sense?
I emailed the convergence page from the manual.

[stushug]

I messed around with everything again today. I was able to clear up most of the problems with the alignment, I'd say on a scale 1 to 10 it's 8.5 or 9. That's way better than it's ever been and I even have the picture centered. I put the top and back covers back on and I'm going to use it as it is and see if if stays good. Thanks for all of the help from everyone!

[JohnCT]

Originally Posted by stushug

I messed around with everything again today. I was able to clear up most of the problems with the alignment, I'd say on a scale 1 to 10 it's 8.5 or 9. That's way better than it's ever been and I even have the picture centered. I put the top and back covers back on and I'm going to use it as it is and see if if stays good. Thanks for all of the help from everyone!

Unfortunately, that model doesn't have a very good convergence adjustment system. Earlier units had an adjustment for global geometric patterns (keystone, parabola etc.) and specific area adjustments like geometry for each color. I do recall seeing the later models that combined red and blue into one adjustment.

This later version was better in that the improvements in yoke winding (and I suspect maybe factory matching) made less adjustment necessary, but less adjustments mean you can't get it perfect either.

These weren't great at their very best, and I suspect you got it as about as good as a pro would get it by your description.

John

[Brady_14]

I just purchased one of these recently. it's not working currently, needs some repairs but, while it worked i loved the thing. Didn't really have a focus issue, but it wasn't really used regularly, so there aren't a ton of hours on the tubes. AFAIK it was put in a repair shop around the mid 1980s, had some capacitors replaced (evidence from tape overtop of the capacitors changed), and sat in a storage unit until i purchased it in june. Trying to find some help repairing something like this, becuase i tried digging into it, and it was more complicated than i thought it would be. so many boards, haha. At least the cables are labeled and not soldered onto the other boards.

[jbattles]

well whats its doing? show a picture of the screen, pic of chassis and someone can chime in and send you in the right direction. Service data might be hard to find on a almost 40 year old projection set.