Gentlemen,

If anyone has come across a spare YA board, please let me know.

Jean might still be able to fix the one we've sent him but I'd like to have an alternative in the unlikely case he can't fix.

Also, anyone with a whole G90 for sale for parts, please contact me.

Cheers

I will have a scrap G90 in about 10 days. Unless it's absolutely mint, I'll be parting the whole working set out.

Jean might still be able to fix the one we've sent him but I'd like to have an alternative in the unlikely case he can't fix I'm not optimistic Oliver since your board exhibs the same failure that I've got on one of my old G90 (needed Sony servicing in San Jose). I will confirm this diagnostic soon. Thanks to be patient ;)

John

John,

Please post all your findings even if you can't fix it. Does anyone know what Sony is capable of doing different when repairing these things? I mean, we have some VERY capable and knowledgeable people here trying to repair the boards. Does Sony swap out the board with a new one?

Thanks!

Doc

John,

Please post all your findings even if you can't fix it. Does anyone know what Sony is capable of doing different when repairing these things? I mean, we have some VERY capable and knowledgeable people here trying to repair the boards. Does Sony swap out the board with a new one?

Thanks!

Doc

No more new YA boards available from Sony. From what I understand there are some proprietory chips on the board and these are the cause of this failure. Sony are happy to replace these components on your card and charge you the cost of a new board, which currently is listed at ~$1800.
John can you let us know what symptoms this pj is exhibiting. Is this the problem that Terry reported causing the 3 tubes to lose the spot kill capability resulting in nuked tubes?

That is indeed the problem. Sony won't sell the chips required to repair the unit. Removing the chips needs someone skilled at changing SMT chips, but if you can't get the chips, you're effed. To be polite..;)

No more new YA boards available from Sony. From what I understand there are some proprietory chips on the board and these are the cause of this failure. Sony are happy to replace these components on your card and charge you the cost of a new board, which currently is listed at ~$1800.
John can you let us know what symptoms this pj is exhibiting. Is this the problem that Terry reported causing the 3 tubes to lose the spot kill capability resulting in nuked tubes?

As I reported in the thread about the G90 that had a spot kill failure, the failure was in the PA board NOT the YA board as was first told to me. In the PA board failing intermitantly (and I was able to reproduce the failure) when it happened the protect circuit for scan fail was not engaging the way it was supposed to thereby burning the tube. It is interesting to note that I could get the PA board to fail with the same error code fairly regularly.......but not every failure lead to spot fail.

Terry

Thanks Terry. So we'll wait to hear from John as to what symptoms the YA board failure was exhibiting.
OT but any word from Mike as to when the G90 mods will be available? Seems that the project has come to a standstill, as we haven't had any updates.

Thnaks Terrry. So we'll wait to hear from John as to what symptoms the YA board failure was exhibiting.
OT but any word from Mike as to when the G90 mods will be available? Seems that the project has come to a standstill, as we haven't had any updates.
There was a second G90 that I got that had spot burn that had a problem with the YA board. By the time I got it it was stuck in a red 88 mode (micro not booting up) and I found the problem to be a shorted buffer chip that was holding the micro from booting. I fixed that but not that YA board seems to want a firmware upload but won't accept it. What caused the spot burn on this PJ I am not sure. Previous owner tried to change the Dallas chip and may have caused the problem with his inexperience.

Terry

OT but any word from Mike as to when the G90 mods will be available? Seems that the project has come to a standstill, as we haven't had any updates.

I'll be posting on this this coming week. Everything is still go for the G90 mods, it's just that they were on hold because I first needed to repair a YA board in order to work on another issue with the G90. That issue is a slight streaking problem. So for now, I'll just have to move forward with things as they are, and maybe someday get back to the other issue. Because I don't have a complete and working test G90 to take things to the next level.

I was also hoping to do some screenshots showing the performance differences, but that's being hindered due to the space I have in my shop.

I'll get back to this tomorrow, and we'll start whatever process we need to move this forward.

Thanks Terry. So we'll wait to hear from John as to what symptoms the YA board failure was exhibiting.John can you let us know what symptoms this pj is exhibiting. Is this the problem that Terry reported causing the 3 tubes to lose the spot kill capability resulting in nuked tubes?Hello Lewis,
Oliver's customer defective YA board exibit the same failure I've got in january 2007 when I bought my second G90 unit from Curt Palme. All the story is explained in here : http://www.avsforum.com/avs-vb/showthread.php?t=735051
To sum-up the story :
The symptoms are shaking image geometry/brigthness/contrast/... since wrong digital potentiometer values feeded from YA to BA/DD/DE/DF boards through I²C serial lines. Since I chase this failure for a long time, I discovered that this was cause by a Sony brand IC that I was unable to find as standalone part. I was forced to send the board to Sony Repair center at San Jose to let them replace this Sony chip themselves. This costed me almost the same price as a brand new YA board :mad: (that is no more available from Sony)

As said by Terry, this failure has nothing to do with spot burn.

John

the gentleman who had the spot burn problem ...

he pulled the YA board while the unit was still powered (in standby)
his first reaction when i asked him if he'd removed the power cord was "why? its was in standby"... doh!


that's what caused the spot burn :(