Picked up a bahemoth plasma TV not too long ago and just now getting around to looking at it.
No picture but you hear the TV static (white noise) playing loud and clear.
The back was already taken off (and no screws were provided) as the previous owner had already taken a look.
But it seems they didn't get too far and just left it.
When I first took a look I was amazed at how pristine the inside looked.
Its as if the TV had been in a time capsule.
Caps looked like they were just pulled off the self.
Copper coils had no sign of corrosion on them whatsoever.
Not a speck of dust.
Very beautiful.
I tested for VS and VA and saw nothing.
A cursory look over all the boards did not reveal anything at all.
On the power supply everything was getting voltage except the sustains.
I pulled the PS off and took a look at in on my bench.
None of the fets were shorted and all of the solder joints were perfect.
As if this TV had never been turned on.
I put the PS back in and went to look for a service manual which I found with ease online.
On page 51 there were was a quick troubleshooting guide on how to interpret the LED status lights on the I/O board but I found it sort of confusing on what the lights meant.
In fact, the light pattern I was getting was not actually described in the guide.
Power supplies of today won't even power on if they detect a fault or short but this one seems to supply power to all systems except the panel so it stands to reason that the issue was with the panel or its boards.
I disconnected the sustains and powered the TV up but the power supply didn't power up at all.
I reconnected the sustains but pulled off the bottom buffer and got half a picture.
I then replaced the bottom buffer and removed the top one.
No picture.
So my issue is with my bottom buffer.
I took it to the bench and tested it for shorts.
I found one at the very end.
As you can see here the driver bubble up a little and this is where the short comes from.
I then realized that this driver looks different than the others.
It didn't have the protective gel around its pins and there was flux on the board which was uncharacteristic for such a pristine TV.
This TV has been worked on and these chips have been replaced once before.
The markings on the original and replacement drivers are the same (TI SN755866).
The soldering job looked descent (or at least better than I can currently do).
I am happy to have diagnosed the issue but now I am at a crossroads on what to do.
I could order the driver and try my hand at soldering flat ICs as I sourly need the practice but then what.
I feel this TV needs to be put out to pasture.
Its VERY heavy for a 55 inch television (130 lbs or 59kg), barely qualifies as HD at 1366 x 768 resolution and I came with no accessories like the stand, remote, etc.
That being said I have a bit of nostalgia for Hitachi plasma TVs.
My first real TV purchase was a Hitachi Director's Series P60X901 60-inch plasma HDTV.
Its still going strong at my mother's house and has given us very little problems (except a PS replacement a long time ago) and has outlasted several newer more advanced successors to the living room TV stand.
Haha
So what do you guys think should be done with these TVs as we get them?
No picture but you hear the TV static (white noise) playing loud and clear.
The back was already taken off (and no screws were provided) as the previous owner had already taken a look.
But it seems they didn't get too far and just left it.
When I first took a look I was amazed at how pristine the inside looked.
Its as if the TV had been in a time capsule.
Caps looked like they were just pulled off the self.
Copper coils had no sign of corrosion on them whatsoever.
Not a speck of dust.
Very beautiful.
I tested for VS and VA and saw nothing.
A cursory look over all the boards did not reveal anything at all.
On the power supply everything was getting voltage except the sustains.
I pulled the PS off and took a look at in on my bench.
None of the fets were shorted and all of the solder joints were perfect.
As if this TV had never been turned on.
I put the PS back in and went to look for a service manual which I found with ease online.
On page 51 there were was a quick troubleshooting guide on how to interpret the LED status lights on the I/O board but I found it sort of confusing on what the lights meant.
In fact, the light pattern I was getting was not actually described in the guide.
Power supplies of today won't even power on if they detect a fault or short but this one seems to supply power to all systems except the panel so it stands to reason that the issue was with the panel or its boards.
I disconnected the sustains and powered the TV up but the power supply didn't power up at all.
I reconnected the sustains but pulled off the bottom buffer and got half a picture.
I then replaced the bottom buffer and removed the top one.
No picture.
So my issue is with my bottom buffer.
I took it to the bench and tested it for shorts.
I found one at the very end.
As you can see here the driver bubble up a little and this is where the short comes from.
I then realized that this driver looks different than the others.
It didn't have the protective gel around its pins and there was flux on the board which was uncharacteristic for such a pristine TV.
This TV has been worked on and these chips have been replaced once before.
The markings on the original and replacement drivers are the same (TI SN755866).
The soldering job looked descent (or at least better than I can currently do).
I am happy to have diagnosed the issue but now I am at a crossroads on what to do.
I could order the driver and try my hand at soldering flat ICs as I sourly need the practice but then what.
I feel this TV needs to be put out to pasture.
Its VERY heavy for a 55 inch television (130 lbs or 59kg), barely qualifies as HD at 1366 x 768 resolution and I came with no accessories like the stand, remote, etc.
That being said I have a bit of nostalgia for Hitachi plasma TVs.
My first real TV purchase was a Hitachi Director's Series P60X901 60-inch plasma HDTV.
Its still going strong at my mother's house and has given us very little problems (except a PS replacement a long time ago) and has outlasted several newer more advanced successors to the living room TV stand.
Haha
So what do you guys think should be done with these TVs as we get them?
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