Hyundai plasma HY4210 buzz no picture

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Well. This might be the ending post to this thred.
This evening I got the Y-SUS board up and running.
You know, the problem was an unstable Vsetup.
The problem was a faulty TL431A in the Vsetup DC/DC which made the regulation disappear. Replaced this and trimmed Vsetup at 215V and the set performs brilliant again.
Of course, as usual, I'm a little worried about the hybrid temp of this undersized heatsink. Bad design practice but smart to limit lifetime of things......

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Please, may anyone give me some input to this.
I also intend to leave out the +5V to the Y-SUS board.
Anyone tried this?

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Is it safe to power up a Y-SUS board on the testbench?
I just want to test the DC/DC packs. But I don't know if something may dislike this kind of operation.

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Latest news.
The problem with too low -Ve and -Vy were caused by bad DC/DC packs on Y-SUS board. Changed the Y-SUS board and got these voltages up and running at spec. (-35V and -65V).
Of course something else isn't going my way. The DC/DC converter for Vsetup should regulate at 215V, but this is jumping up and down from 150-315V. This in turn makes the screen change brightness up and down accordingly.
At some point it went down to zero aswell, which makes the screen go black.
I used this Y-SUS in another plasma a while ago, and the screen suddenly went out, and I didn't know why. Now I know, it was caused by the Vsetup DC/DC regulator.
So, speaking about repairing the DC/DC, I changed the 4 pin regulator, three electrolytes, checking diodes, etc etc, but it continues unstable operation.

Is the unstable Vsetup caused by the DC/DC or can it actually be some other problem on the V-SUS board?

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Did some additional work on the Hyundai plasma this evening. Not very successful though...
As I told above the screen is full of sparks, mainly red. Colours are not natural so I began consulting panel manual to trim the Y-SUS board DC/DC packs correctly. The sticker on the panel gives the voltages.
I trim Vsetup to 215VDC. (I noted that a higher voltage like 230VDC will reduce the sparks a bit)
I trim Vscw to 115VDC.
I try to trim -Ve to -35V but it won't reach more than -32V.
I try to trim -Vy to -65V but it won't reach more than -28V.
Appearently something is bad here, and probably the reason for the strange colours and sparks visible.
Could a bad panel affect the negative voltages in this way? Or must the failure be isolated to Y-SUS board only.
And further, I note that one of the buffer IC's on the upper Y-buffer board gets much warmer than the rest of the drivers. So, probably another bad bufferboard aswell?
I disconnected this buffer board from Y-SUS but the negative voltages stay the same.
So, could the low -Ve and -Vy explain the behaviour of the panel?

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

definately be VERY careful on adjustments.

I turned a pot a little bit far on a 42 hitachi once causing it blow out the entire IPM, the ER and SUS was built into 1 IPM i believe. heard a loud buzz-saw sound, 2 seconds later, POWWWWWW gone.

What adjustment did you do then? Turning VS above spec perhaps?

[mbates14]

Re: Hyundai plasma HY4210 buzz no picture

definately be VERY careful on adjustments.

I turned a pot a little bit far on a 42 hitachi once causing it blow out the entire IPM, the ER and SUS was built into 1 IPM i believe. heard a loud buzz-saw sound, 2 seconds later, POWWWWWW gone.

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

I've trimmed VA and VS exactly according to panel. VS 189V and VA 65V. Sparkles!
Wiz, I read in an earlier post about you telling as panel ages, it may require another setting of VS and VA. Is it generally necessary to increase the voltages then?
Hypothetical, if I can't get rid of the sparkles, may this indicate a bad panel?

You're right Bill, it's a LG 42V5000 panel.

[Wizard]

Re: Hyundai plasma HY4210 buzz no picture

What what. waking up... Okay.

The adjustments is only on the power supply or such that is for Va and Vs only.

Tweak each one at a time and view the picture bit by bit till sparkles disappears, can go either way. Take care with voltages, they bite and can be lethal.

Cheers, Wizard

[PlainBill]

Re: Hyundai plasma HY4210 buzz no picture

Changed the Y-buffers. Noticed one of the IC's had a small damage on top.
After this the picture is back BUT something isn't OK. Don't know if this involves trimming the Y-SUS board or Z-SUS. The Z-SUS board was changed.
The problem is that the picture has a lot of sparks (especially red) and the colours in the picture are not natural.
Took a picture of the sparks but it's not possible to see so didn't attach it.
I saw a trimmer on Z board but didn't dare to touch it, does it require trimming?

Arghh!!!!

Sorry, I had to get that out of my system. Congratulations on getting it working. I hope you still have some hair left.

I've forgotten the brand of the panel (LG?), but here's a short summary of what has to be done.

1. Read the voltages on the label on the back of the plasma panel. Some of these are generated by the power supply. Adjust them. Some are set on the Y-Sus card. Set those next IF you can find the information. Last, adjust the voltages on the Z-sus card. Either the Service Manual or a 'Quick set up Guide' should help.

Do NOT tweak any pots 'just to see if that helps'. Per Wizard, that can result in the quick demise of the panel.

2. If the sparks are still present, either hope Wizard show up with advice or dig through his old posts on plasma TVs. Within the past year he helped someone with this problem do the adjustment to reduce the sparkles. IIRC, it requires careful tweaking.

PlainBill

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Changed the Y-buffers. Noticed one of the IC's had a small damage on top.
After this the picture is back BUT something isn't OK. Don't know if this involves trimming the Y-SUS board or Z-SUS. The Z-SUS board was changed.
The problem is that the picture has a lot of sparks (especially red) and the colours in the picture are not natural.
Took a picture of the sparks but it's not possible to see so didn't attach it.
I saw a trimmer on Z board but didn't dare to touch it, does it require trimming?

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Thanks for your info. I haven't tried other buffers yet, will do asap.
I did another weird (?) experiment earlier today with this set. I hooked up another plasma TV (Another LG with the same sort of panel) and connected the LVDS cable from that one to the Hyundai. Still no picture.
Don't know if this is possible to succedd though.

[mbates14]

Re: Hyundai plasma HY4210 buzz no picture

there were fets on the buffer boards for god knows what reason.

But All i was saying is the bars are because of the address y-scan missing/broken.

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Aint it the truith. ive pounded my head in the wall over this goofy toshiba. that uses the PDP50X3 series panel/chassis, and parts are crazy expensive.

I rebuilt the YPPD Hybrid-IC IPM and got it up and running. then i got the same exact bars you were having. turns out, the y-scan signal was missing becuase mosfets blew on the buffers, so instead of the address period being able to address the individual Y pixels, it addressed the entire row, no way for the individual pixels to be selected. I replaced mosfets and got it goi ng for a little bit, but eventually failed again.

the person just bought a new TV, so im stuck with this PDP50X3 Panel and parts. the panel is good. but the rest of it, not so good.

So i am out there looking for a prime candidate for a panel swap, like trying to find a TV with a PDP50X3 in it with a busted panel. perfect candidate. Problem is, I dont know of a way to find out what TVs and models of TVs that used the PDP50X3

Do you mean the fets on the Y-SUS board? Or the Y-buffer boards?
I changed the Y-SUS and the bars went away, but still no picture.

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Since I don't know if the SSB works, couldn't find how to activate (if there are any) testmode on control board, I'll hook up another plasma (LG MZ-42PZ44) with its SSB and just wire the LVDS cable to the Hyundai and see what happens.

[mbates14]

Re: Hyundai plasma HY4210 buzz no picture

Yea ive done that once before on a couple of other sets and sometimes the results are inconclusive.

However, i havent tried it for this set. YET... so i may just get to googling and see what turns up.

[PlainBill]

Re: Hyundai plasma HY4210 buzz no picture

Aint it the truith. ive pounded my head in the wall over this goofy toshiba. that uses the PDP50X3 series panel/chassis, and parts are crazy expensive.

I rebuilt the YPPD Hybrid-IC IPM and got it up and running. then i got the same exact bars you were having. turns out, the y-scan signal was missing becuase mosfets blew on the buffers, so instead of the address period being able to address the individual Y pixels, it addressed the entire row, no way for the individual pixels to be selected. I replaced mosfets and got it goi ng for a little bit, but eventually failed again.

the person just bought a new TV, so im stuck with this PDP50X3 Panel and parts. the panel is good. but the rest of it, not so good.

So i am out there looking for a prime candidate for a panel swap, like trying to find a TV with a PDP50X3 in it with a busted panel. perfect candidate. Problem is, I dont know of a way to find out what TVs and models of TVs that used the PDP50X3

Google may be your friend. A few minutes searching and I found suggestions that LG Electronics, Vizio, Toshiba, Audiovox, and Akai all used that panel.

One trick I use is to search for sub assemblies - Y-Sus and Z-Sus typically - and see what brands and models pop up.

PlainBill

[mbates14]

Re: Hyundai plasma HY4210 buzz no picture

Aint it the truith. ive pounded my head in the wall over this goofy toshiba. that uses the PDP50X3 series panel/chassis, and parts are crazy expensive.

I rebuilt the YPPD Hybrid-IC IPM and got it up and running. then i got the same exact bars you were having. turns out, the y-scan signal was missing becuase mosfets blew on the buffers, so instead of the address period being able to address the individual Y pixels, it addressed the entire row, no way for the individual pixels to be selected. I replaced mosfets and got it goi ng for a little bit, but eventually failed again.

the person just bought a new TV, so im stuck with this PDP50X3 Panel and parts. the panel is good. but the rest of it, not so good.

So i am out there looking for a prime candidate for a panel swap, like trying to find a TV with a PDP50X3 in it with a busted panel. perfect candidate. Problem is, I dont know of a way to find out what TVs and models of TVs that used the PDP50X3

[PlainBill]

Re: Hyundai plasma HY4210 buzz no picture

Great! I'm quite amazed how much info there actually is, provided by the manufacturers. Somehow it feels their intensions were quite good in making it possible to repair those animals. It's a pity that spareparts is often no longer available short after production termination.

A lot of information is available. There are also a lot of gaps that can be quite frustrating.

Spare parts are an ongoing problem. I don't know what the situation is like in Australia, but here is the US carrying an inventory of spare parts has serious tax implications. I believe the situation is something like this: A Z-sustain for a 42" LG plasma costs $35 each (parts and labor) to build in a production run of 1000. LG sells them as part of a panel assembly, and marks up them to $50, assuming they will have to replace some that fail in the first year. They also make them available as spares for $150 each. The TV manufacturers mark them up to $295 each. So when LG Electronics of America has 100 Z-sustains sitting in their California warehouse, those cards cost less than $5000 total to build and ship to the US. But they show on their books as a taxable asset worth $29,500.

At the time the TV was being built the panel design group was already working on the next generation of panel that is easier to manufacture, lighter, brighter, and uses less power, and needs a new Z-Sustain. So ther is no point in continuing roduction of the old cards.

At some point the bean (rice) counters at LG say they can't afford to keep the spares on hand (remember, they are paying taxes on every one sitting in the warehouse). They will use some guesswork to estimate how many will be needed, based on the rate of failure seen so far. And they will dump the excess cards on the surplus market for less than $70 each.

PlainBill

[PowerAmpFreak]

Re: Hyundai plasma HY4210 buzz no picture

Great! I'm quite amazed how much info there actually is, provided by the manufacturers. Somehow it feels their intensions were quite good in making it possible to repair those animals. It's a pity that spareparts is often no longer available short after production termination.