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Sometime lost pixels can be the result of bad FFC connections. It can be the solder connections or the cables themselves can develop gaps in their traces. Usually when I see that it's whole lines that are lost though and not just random pixels, but might be worth going over the cables to see...

Sounds like the best course of action. What kind of a test signal should I put up? A greyscale ramp or something? I assume I'm looking at the three cathodes to see how close they are to zero volts when 100% white is displayed, so maybe a grey ramp to white would give me a kind of stepped slope...

Thanks for the reply. I'm generally aware that the smearing is caused by pushing the cathodes too hard. This is all just academic tweaking to see what is possible. I certainly don't expect any miracles, but I'd like to learn more about the electronics and concepts by optimizing what I have to...

I wasn't at all sure about this idea. You're light years ahead of me with all this stuff, so I'm sorry if it seemed silly on my part. The issue I was trying to address is the typical Red smear you get with older tubes. My understanding is that the red phosphors often exhibit ghosting and...

Thanks for your insight. It sounds like after reading your explanation, I could easily substitute VPS10 for the existing VPS07T because the gain is set by the surrounding components and it is not fixed (and therefore the datasheet is telling me the maximum gain (22, 20) and not a fixed gain...

I was looking at the schematic yesterday, and I can't help wondering about the smearing/ghosting at higher contrast levels in higher resolutions. The main video amplifier IC of this monitor is the Sanyo VPS07T, which maxes out at 70MHz, and is generally only really happy up to 56kHz Horizontal...

Thanks. Yes, I have a 100x probe that I used for this purpose with my oscilloscope. I also have a good isolation transformer for my DUTs.

Understood. That might just be the case. I did go through the white balancing act, but I didn't start with the backgrounds all the way down like the service manual said. I think the backgrounds were probably in the middle and not the bottom of travel as SM wanted me to. I didn't realize that...

Thanks for mentioning it. I would have been worried about it otherwise. Actually, after checking all those caps and going over a couple spots on the D board, the instability seems to have decreased a lot. It's no longer breathing when I turn it on. I'm still getting some horizontal breathing...

Okay. I can check the capacitors. I'm assuming it's all those high voltage caps 408, 409, 412, 410, etc. This is the whole D board: The manual states that all called-out voltages are taken with a color bar signal, H:31.47 V:70.1, which is 640x400@70Hz, and that's exactly what I have taken...

Alright. I took a scope reading of the collector of Q403, which is where the chopped supply that is supposed to be 60.9VRMS. There is a waveform on the Service Manual that shows it's supposed to be 660Vpk, and it's more like 1.1kVpk! This seems very not good. I also took a snapshot of Q402's...

Okay. I think I found the issue. There's some problem with the 160V source. I see 155V on the 160V line. There must something blown up in there? This was measured on P903. I see the 24V dead-nuts on Pin 1, Pin 8 is 155V. I tested and replaced any of the bad electrolytics months ago, so it's...

It is interesting. Thanks for the insight. I replaced the 7812, and I indeed got back my 12V, so that's a win. 👍 I ran a couple of test patterns to see if I could spot anything unusual, and I noticed that it's not doing very well on the High Voltage regulation test. This is a test that flashes...

Yeah, it's not bad at all, but I do think there is still something a little odd going on. When I turn it on after it's been sitting, the horizontal width will bounce in and out a little bit until it warms up. I'm not totally sure what that's about, but I noticed awhile back that the 12V supply...

I had to go in and remove all the yoke wedges and start over. whoever replaced the tube did a really bad job of it and all the convergence adjustments and such were messed up. After doing beam landing, static convergence, dynamic convergence, white balance and geometry, it now looks pretty...

Finally got it back in the case, and I had a minor hiccup. One of the capacitors on the DA had broken a trace and it stopped working again. After three and half hours, I tracked down the problem and set it right again. When I finally got it in the case and looked at it straight on a desk, I...

Thanks! So I spent some time messing around with the controls and I also replaced IC303 and IC301 with NOS ICs and that cleaned it up a little bit more. Not 100% perfect, but very close to, to the point that I think it's convergence or it just needs a couple magnetic strips.

It was testing at 17V on the Base and 24V on the Collector. No, it did not. I decided to replace IC304 because I got a couple of them. D311 was not fitted from the factory. I actually purchased the exact diode (still available), but I didn't fit it because I thought they must have left it...

I found an area that seems off. Q310 has blown up three times now, and I thought it was because of something I did wrong, but now I'm starting to think it might be the result of something else. I found that the voltages on Q309 were too high. The Base and the Emitter are supposed to be around...

There's nothing that seems to make the sawtooth on the emitter of Q315 bigger. If I turn the Pin Up to the right, it will pull the square wave down a bit in a funny squiggly way, but it doesn't make it taller. The Side Pin controls don't seem to do much of anything at all. The only action I can...