Horizontal lines on a Philips 50pf9830a plasma

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Customer says the magic sparkles were always there and he's not worried about it and he's happy with the fix, so it looks like this beast is finally done!

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

I should add that when we bought the Y upper and lower buffers, we also bought Y-Sustain, just in case there was more wrong with that current Y-Sustain than the blown capacitor that I replaced. I'm wondering if there was more wrong with it and maybe we should be using the replacement Y-Sustain. It's bit of work now to switch it out and I just wanted some suggestions on what you guys think might be causing the sparkles. From what we can tell, just the upper left side of the screen (maybe the upper half, starting at the middle, going up, but just on the very left hand side....) I can show pics if you guys want to see it.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Ah shit. I'm sorry to bother you guys again. I got the new tuner board installed and it fixed the tuner issue. Now that we got a picture on the screen, we notice sparklies. Just in the upper left hand corner though. They're very noticeable when there's a darker scene.

I've been reading how to fix these. We've double checked the voltages that we could find on the sticker / power supply board. The Y-Sustain is a Samung board, so maybe there's some pots that can be adjusted, but it'd be a guessing game, we can't find a service manual for this TV or that Samsung Y-Sustain board.

Any suggestions on how to fix the sparklies? Thanks!

[freakaftr8]

Re: Horizontal lines on a Philips 50pf9830a plasma

Good deal. You're welcome

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

I just noticed that little mess up is only noticeable if you're looking from the top of the TV down, like standing over it. You can see a couple lines going across, just in that one little area. Not sure if that's one of those top buffer boards (like the E buffer board), or what, but I don't think it's a big problem and I'll probably just not worry about that, unless you guys think I should.

Thanks soooooo much for the bad Y-Buffer suggestions! That really was the problem and I wasted a lot of time testing other components (X-Sustain, IPMs, Y-Sustain). Some of the time wasn't really wasted I guess. Adjusting the voltages was important. I went through with the new buffers and made sure they were all adjusted. There's a few I can't find pots for, like Vg (I think). 12V is off a bit and I can adjust that, just not with the TV on, which makes it really hard to fine tune. Should I worry about that?

I also now need to replace the main logic board, the one where the tuner doesn't work. There's a board under that with a blinking LED and a couple solid LEDs. I think the blinking LED is telling me the logic board has an issue. I'm just hoping it's the logic board (with the tuner) and not the board underneath it.

Thanks for the help!!!!!!!

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Okay, freakaftr8, the y-buffers came today and I just put them in. It's almost fixed. It greatly improved it, but there's one group that's still a little off, on one of the sides though, not really the whole way across the TV. When my wife comes home, I'll get more pictures and double check all the voltages and stuff.

But it really seems like it was the Y-Buffers. Maybe I should put the original X-Sustain board back in, seeing how that wasn't bad at all. I wonder if there's still more wrong with the Y-Sustain, besides that bad cap, that might be causing the little bit of lines.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Looks like bad buffer boards to me. I just deal with this on a 50 inch Philips. Top buffer boards loading down the system. It may have destroyed the lower already because they're connected in series buy a white clip period I'd swap out both buffer boards. The Tell-Tale sign is that the middle that screen is still okay

I just want to make sure you didn't miss the post where I said I found a bad capacitor on the Y-Sustain. I replaced it but nothing at all changed. Because the Y-buffers are fed by the Y-Sustain, is it possible that there's just more wrong with the Y-Sustain, like that voltage regulator that looked burned, that might be causing this?

What's a white clip? Both buffer boards are really expensive. ShopJimmy didn't have them instock but if they did, they would have been around 190$ (without shipping) I think. The Y-Sustain is 24$ (free shipping).

None of the ICs on the buffers appear to be damaged (ie, no holes, no missing tops, etc). I wish I could find away to verify that the Y-Sustain was working correctly before replacing those buffers.

[freakaftr8]

Re: Horizontal lines on a Philips 50pf9830a plasma

Looks like bad buffer boards to me. I just deal with this on a 50 inch Philips. Top buffer boards loading down the system. It may have destroyed the lower already because they're connected in series buy a white clip period I'd swap out both buffer boards. The Tell-Tale sign is that the middle that screen is still okay

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

We went through and adjusted the rest of the settings based on the sticker using the test points we found. Ve was off by 10VDC or so. Now everything's within a .1VDC or .2VDC. There's a 12V test point we found that reads 11.93VDC. We found a pot for it, but didn't know if we should adjust it.

One thing I want to point out. On the Y-sustain board, the one that had the bad capacitor, there's six connections. On the screen, my wife noticed there's six bars that seem to line up with those connections. The third one down has no horizontal lines at all. We unplugged the top most connector and turned on the TV and it kills the top most picture, but also removes the lines.

To me, this says those Y-Buffers (scan drives I think they're called) and / or the Y-Sustain is the problem, after all, the Y-Sustain did have a bad capacitor. What do you guys think?

Thanks for the help guys.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

The new X-Sustain came today and I installed it. Same issue. I hit menu, I see all the horizontal lines. Before I installed, I checked the continuity of the IPMs on the new X-Sustain and the old one, they were the same. To me, this said it wasn't the IPMs.

I'm going to wait until my wife gets home to see if there's voltage going to the new X-Sustain. Last time, measuring at the connector on the PSU that goes to the X-Sustain, I didn't get anything. I did find some test points for the signals though (ie, Ve). Is there a chance that the power supply might be bad or if something like Ve is really off (ie, 100VDC instead of 90VDC), could that cause these lines?

I want my wife here incase I do something stupid by mistake and get hurt.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Reece can you link that video i have got a scope too now so be handy to see the procedure etc.

I believe the service manual I uploaded has the procedure, at least for that Samsung X-SUS. If I remember correctly, you remove one of the ribbon cables from the side and check it. One thing that might be of interest, in the service manual, they show a waveform of how it's supposed to look. There's probably a good chance that waveform might be unique to that Samsung board. So, for example, with another board (maybe a Pansonic), the procedure and waveform might be totally different.

[vinceroger69]

Re: Horizontal lines on a Philips 50pf9830a plasma

I do have a scope. You know a lot more about plasmas than I do. I was just trying to verify there wasn't more wrong while waiting for the new Xsus board to come.

Thanks for the help. It's supposed to be here on Friday, but because of the storm, it might be a bit late.

Hopefully the replacement board will fix the issue but we have been seeing a lot of threads where replacement boards are turning up faulty, so if reece can link that video it may help in your repair just incase the replacement dosnt fix the issue.

[vinceroger69]

Re: Horizontal lines on a Philips 50pf9830a plasma

Bit of faff this is, the Xmain seems to be the issue. You have a scope right ? If so will link thread so you can set it up to trigger sustain waveforms that should be generated by the Xmain.

Reece can you link that video i have got a scope too now so be handy to see the procedure etc.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Bit of faff this is, the Xmain seems to be the issue. You have a scope right ? If so will link thread so you can set it up to trigger sustain waveforms that should be generated by the Xmain.

I do have a scope. You know a lot more about plasmas than I do. I was just trying to verify there wasn't more wrong while waiting for the new Xsus board to come.

Thanks for the help. It's supposed to be here on Friday, but because of the storm, it might be a bit late.

[ReeceyBurger123]

Re: Horizontal lines on a Philips 50pf9830a plasma

Bit of faff this is, the Xmain seems to be the issue. You have a scope right ? If so will link thread so you can set it up to trigger sustain waveforms that should be generated by the Xmain.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

I must have been doing something wrong here, because I'm looking at the PSU and I see two very large caps. The positives are connected together, and I follow the trace, it goes to the Vs on the connector for the Y-SUS and then goes directly to the Vs on the connector for the X-SUS. If the Y-SUS has a voltage reading for the Vs signal, the X-SUS has to have one. They appear to all share a common ground (to me, it looks like there's just a very big ground plane that almost everything uses for ground).

Gonna start pulling some components and testing them. Maybe there really is something broken on the X-SUS that's just breaking the loop, so the electricity can't make it back. That would explain the no voltage readings on the X-SUS connector, wouldn't it?

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

did you say you had found a bad resistor on the psu in one of your previous posts?

I did say that, but I'm not 100% sure it was a correct statement. I've now pulled the psu and am getting ready to pull that resistor to check out of circuit. I noticed there's some rust on the legs and was thinking maybe that was affecting my reading. It's weird though, there's a test point for Ve right near that connector, and that test point shows voltage, but when I put the red probe in the Ve pin on the connector, I don't get anything. I made 100% certain I was touching the metal that goes around the wire. I used a screw for ground. For the Y-SUS board, that screw worked. Maybe the X-SUS needs a different reference for ground though?

I dunno. I'll let you know what I find out. I'm also going to pull a capacitor that's very close to the connector. I can see the traces going to the connector from the cap. I'll check that cap to make sure it's good. I found more fuses too. Red round ones, they look a bit like short electrolytic caps, but they're actually fuses. I didn't pull any, but I tested the continuity across them (in-circuit) and they all read 0.000 ohm resistance, so I'm thinking they're good.

[vinceroger69]

Re: Horizontal lines on a Philips 50pf9830a plasma

did you say you had found a bad resistor on the psu in one of your previous posts?

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

Guys, I know I don't know a lot about plasmas, but I really don't think it's a blown IPM on the X-SUS board. There's two IPMs on the X-SUS. I went through with a DMM set to continuity and measured the resistance between all the pins on each chip. Both chips show the same continuity for each pin sets. There's only a couple pins that on one side that measure 0.000 resistance with a pin on the other side, but on both IPMs, they measure the same. So unless both chips blew, I don't think the IPMs are bad. I think it's something with the power supply.

[Spork Schivago]

Re: Horizontal lines on a Philips 50pf9830a plasma

The X-SUS board's PBA number is LJ92-01045A. Maybe I can just find a schematic for that board...