CurtPalme.com Home Theater Forum

[matt697845]

Hello all, a few months ago I posted about acquiring 2 Sony G90's. Although they will probably be in storage for about a year due to current living situation, I would like to get the Dallas chips on one or both of them replaced ASAP. It appears that one of the YA boards has the dreaded IC421 failure (shaking image when navigating the menu). Where is the YA board and how do I remove it? Basically what I'm looking for at this point is a reputable person on this forum to whom I can mail the boards to, copy and replace the Dallas chip on the good board, and confirm on the other board whether it is indeed a bad IC421, or something else, at a fair price. I'm not looking to replace it yet due to cost.

Thanks!

[Curt Palme]

No need to change the Dallas chip now if you're not using them. The YA board is the one under the RGB input board.

Craig Rounds or myself can test them. PM pr email me.

[Curt Palme]

No need to change the Dallas chip now if you're not using them. The YA board is the one under the RGB input board.

Craig Rounds or myself can test them. PM pr email me.

[mc86]

I don't think I'll get in trouble with showing you where/how to remove the YA board, so here are some pics I took from a machine I parted-out to help pay for a fraction of my HT equipment.

cheers,
Matt

[matt697845]

Thanks for the useful pictures!

Regarding the Dallas chips, I read on this forum that the battery in them is only reliable for about 10 years, after then they can fail at any time, loosing all setting info and possibly risk spot burning/destroying the tubes. Since it contains a battery responsible for keeping the setting info stored, its constantly being consumed, even when not in use, correct? And since they are both probably over 10 years old they could fail at any moment, and at the least loose all setting and serial information permanently, right? Am I misunderstanding what I read somewhere?

@Curt, PM sent

[CIR Engineering]

I would recommend new Dallas chips right away. If you send me the boards or Dallas chips I can copy the original data and transfer it to new Dallas chips. I'd also be happy to look at your problematic YA board, though it does sound like a dead IC421 for which there is no fix. If you are planning on using both G90's, i do have one good YA board in stock that I would be willing to sell because I think I have enough spares right now for my clients.

craigr

[Curt Palme]

the only reason I said not to bother at this point is that if the sets are going to sit there for a year, why waste that year of the Dallas chip? Craig can transfer the base information over, I can too, but I never bother, as that way the next customer knows that he's got a new Dallas chip with between 12-40 hours of runtime that I put on the G90s I sell.

Up to you, nothing wrong with changing them right now either.

[Curt Palme]

the only reason I said not to bother at this point is that if the sets are going to sit there for a year, why waste that year of the Dallas chip? Craig can transfer the base information over, I can too, but I never bother, as that way the next customer knows that he's got a new Dallas chip with between 12-40 hours of runtime that I put on the G90s I sell.

Up to you, nothing wrong with changing them right now either.

[bobcollins12]

Looking to solve a menu problem with my G90. Horizontal jittery movement of characters - jerky movement slightly to the left and then back. Unstable. All other PJ functions seem normal. Corrected the problem briefly while navigating the menu for a few minutes (changed contrast and brightness briefly and back). But it re-appeared the next time I powered up the PJ. I noticed a reference to an IC421 in this post. Could that be the problem? Could it be caused by anything else??
I also saw you may have a YA board for sale. Would that solve the problem... and how much is it?
I do have a Dallas chip I have been contemplating swapping out along with the EPROM programmer device for copying the data. Just been putting it off. Busy with other stuff. And - I'm a little nervous about actually doing it. Seems so many things could go wrong. (But I do think I understand the process well enough). Could you take care of the Dallas chip swap-out and solve the menu problem at the same time? My G-90 is about 11-12 years in service. Don't know when it came off the assembly line. Has worked flawlessly all that time. I just re-did the entire set-up myself when I put in a digital board about a year ago. It looks great. (I had William Phelps do the first one around '03). Just one more question. I'm curious how common this menu problem is. Never heard of it until I did a little research here. Thanks for your time. Appreciate any advice you might have.
Bob

[CIR Engineering]

[bobcollins12]

Craigr,
I really appreciate you taking the time to answer. I feel a little relieved that it's not that chip that seems to cause all the trouble.
My menu jitter problem may be intermittent also. Just discovered it recently and it became stable again after a few minutes of navigating around the menus - specifically the brightness and contrast. But - it was back the very next time the PJ was powered up - and still not resolved as of now.
Maybe it would be best to wait and observe for a while. If it's definitely persistent and won't go away anymore I'll be more than happy to send the boards to you. It's great that somebody actually knows how to solve things like this.
I'm not entirely all thumbs when it comes to electronics, but I don't trust my soldering abilities, and I hear these boards don't like being mistreated. Speaking of which, how is the best way to send them with no chance of damage during shipping...static electricity, etc. Use a lot of bubble wrap?
Quickly, on another topic, I am using memory #14 for analog and #17 for digital inputs. Both are "protected". I have #14 stored in the service block. (I just changed/updated the #14 data to better fit the digital input needs - while using a digital input... test screen patterns, etc.). If the Dallas chip battery quit, I'm assuming neither memory would be available in the user block, but #14 would not be lost. I'm guessing I would have to load it manually every time I used the projector (or would that be automatic?). Not the end of the world but a little extra trouble. To use Input B (Digital), however would be another story... I guess, would require entering all the numbers I've written down for the whole process to complete the set-up adjustments, and only then could I use the Projector for digital viewing. I've thoroughly read the dealer installation manual, but it's very confusing in this area. Still, it obviously seems a good idea to replace the chip before it fails. I just dont' want to be caught "fixing something that ain't broke". Know what I mean?
Side note - BTW, I just checked - the menu is fine with both analog and digital input...(for now). It wasn't yesterday.
Thanks,
Bob

[CIR Engineering]

[bobcollins12]

OK. I just got through reading all the info you sent. I appreciate your thoroughness. You've scared me sufficiently into taking some action. I do have a blank Dallas chip purchased about a year ago (it's still in the original packaging) and the eprom programmer for swapping memories over. Unless you scream at me not to do it myself I think I'll give it a try. According to all I've read on the subject, this doesn't involve any soldering and any other chip replacements. Just removing the Dallas Chip off the board, swapping memories and replacing with the new one...right? I understand it just needs to be lifted up, unplugged - not unsoldered. I do understand the anti-static requirements. My only fear is the same as when one works on a car...there's always something unexpected that wants to go wrong.
I printed out several posts from a while back about the procedure. Be glad to accept any advice or new info you want to pass along. Certainly if all else fails, I'll be sending the boards to you to do it right. You never said what the costs would be...?
Please don't think I don't trust your abilities - or info. I know I have very limited knowledge on the subject, but I do have a question based on something I read a year or two ago. I may even be remembering it wrong. But I was under the impression that the service memory was stored on another chip besides the Dallas chip, one that was located right next to it. Is that not the case? If that was so, the service memory would still be intact if the Dallas chip went bad. That's why I thought there would be something left to at least run the PJ with until the chip was replaced. If that's not the case, it seems the picture is more dire than I had imagined.
I guess I would be considered impertinent if I were to suggest - Why in the world would they make something so expensive in such a manner that it could be made completely unusable or unstable by a component that was so difficult or dangerous to fix or protect against failure?? But I guess the same goes for the infamous IC421.
Another misconception I might have is that the chip would last quite a lot longer if power was never interrupted to the projector. I'm going under the assumption that the battery would not have to work anywhere near as hard (thus saving energy potential) if it was rarely called upon to do anything. But...maybe it just wears down no matter what, thus, the "ten years".
Anyway, let me know what you think. I don't want to do anything stupid or foolish...(It has happened before).
Sounds like you do a general swap-out of parts on the boards that might have a tendency to fail over time while you are doing the other required work - capacitors, etc. Let me know what the whole thing would cost...and about how long it would take.
Thanks again,
Bob

[CIR Engineering]

[quote="bobcollins12"]OK. I just got through reading all the info you sent. I appreciate your thoroughness. You've scared me sufficiently into taking some action. I do have a blank Dallas chip purchased about a year ago (it's still in the original packaging) and the eprom programmer for swapping memories over. Unless you scream at me not to do it myself I think I'll give it a try. According to all I've read on the subject, this doesn't involve any soldering and any other chip replacements. Just removing the Dallas Chip off the board, swapping memories and replacing with the new one...right? I understand it just needs to be lifted up, unplugged - not unsoldered. I do understand the anti-static requirements. My only fear is the same as when one works on a car...there's always something unexpected that wants to go wrong.
I printed out several posts from a while back about the procedure. Be glad to accept any advice or new info you want to pass along. Certainly if all else fails, I'll be sending the boards to you to do it right. You never said what the costs would be...?9/quote]
If you have the hardware to make the copy you can probably do it yourself. What I would suggest is trying to write all FF to your new chip first before inserting your original chip. Your primary risk is scrambling the data on your original Dallas at which point it will be lost. If you write blank data to your new chip first you will be able to test your hardware and verify that you have the voltages, chip part number , etc set correctly.

When you pull the original out of the socket use something non-conductive. I have seen Dallas chips get their data scrambled when pins are crossed.

If you need prices on any of my work the best thing to do is email. I don't usually put prices on public forums.

[bobcollins12]

Hi,
I started writing then it just went away. If you get an unfinished message - that's why. Anyway, continuing...
Thanks again for your insights. Especially the one about being careful about not shorting the chip when removing. Good advice.
I will send you an e-mail about pricing, etc. Now that I've completed my "5" required posts, I can do that. I know you've been around for a long time. Obviously, I'm new. But I'd like to play devil's advocate for a moment - not to dispute your knowledge, but to wrap my head around something that doesn't make sense to me. Referencing some of the posts you refer to about where data is stored: on pages 130 - 132 of the Installation Manual it discusses Memory Blocks and their use. Specifically, it says that the Service Block backs up data that is stored in the User Block. It's not logical to me for the designers to store the back-up in the same place as the primary data. After all, isn't that the purpose of a back up - to make something available that has been otherwise lost...? This data should not go on the same chip. It's just so elegant:

User Block Data - IC333
Service Block Data - IC334
Firmware - IC234

This is what I've seen in many places on the system design. They all seemed to be so sure of their 'facts'. Perhaps there's a Sony tech sheet somewhere that says exactly what's where. I'd love to see it if you have one.

Anyway, why back up something in the same place as the primary info??
Now, I can take you at your word based on much greater experience that both data blocks are in the same place, but can't you see why an engineer would question that. As recently as 2011 there were several PJ owners that sounded like they knew what was going on; they believed those three lines above were fact. Taking this a little further, on page 131 there's a flow chart that just screams that the User block and the Service block are not in the same place. OK, I understand that they still could be (physically) but why would they do that? Further, on the next page, 132, we are advised (recommended) to store adjustment data that's in the User Block to the Service Block...with the specific purpose of being able to "easily reset the projector to the previously adjusted conditions". That would not be possible if that memory was stored in the same place. So, what would be the purpose, i.e., why bother - why go to the trouble of doing what they "recommend". The whole RESET procedure seems useless if it depends on one chip not failing...and it is specifically the one that apparently is most prone to failure, and the one that as you said is..."supposed to be maintained by a professional who knows to change the Dallas chips on a cycle". OK, 'nuff said. It's a case of it is what it is. If everything is indeed stored in one place as you say and vulnerable to being lost all at once, it's just a stupid design, and I just don't get it.
I'm a former airline pilot and I can tell you for a fact that none of the many back-up systems we had on our planes were put in a place where if the primary system failed it would take out the back-up system as well. Thank God none of the Boeing engineers were that idiotic.
For what it's worth I do remember reading somewhere about a guy who lost his Dallas chip, then couldn't restart the projector. All kinds of error codes. He installed a new Dallas chip. He then had to re-flash the firmware to get it going again - probably in the emergency mode. Did that and after recalling the Service Block data all his settings were still there - even though they should have been lost with the chip's demise. It seems that data had to have been stored somewhere else or it would have gone away with the old chip that failed. I don't know - it's possible I don't remember the story right.
Sorry I got off on a bit of a rant. I really do appreciate the info. And I will take it as fact unless something changes. As I said the manual is quite confusing in places. I'm just doing my best to make sense of it.
Honestly, I don't know if I can figure out how to set up this EPROM programmer. It's not one of the automatic ones. I need to know the dip switch settings and there are several jumpers on the board. I don't see any info on how to set them. The on-line instructions seem to go on forever. Maybe just the small section on EPROM programming is all I need to read. I downloaded the latest software, but it too is confusing. Maybe I should un-retire and go back to flying for a living. Thanks again for your help. Really - wrap the board in aluminum foil - that won't hurt it? I looked today and didn't see any anti-static bags for mailing. If you can e-mail cost information, send to bobcollins12@yahoo.com.
Bob

[CIR Engineering]

[Spanky Ham]

I have mentioned this before, but a friend who does a lot of shipping for his business told me to use shredded newspaper. His claims went to almost zero after switching.

[bobcollins12]

I understand your point completely that you don't want to argue a point you know to be true from experience. My point simply is that I don't have the knowledge - or the experience. That's why I ask questions. And as you can see if the manual says something it doesn't mean, how am I to know what to believe. I do still say what they did doesn't make sense.
Yes, I understand the chip has to come out to swap it with the new one. The one I have was ordered about a year and a half ago. I've just been busy and a little scared to mess with it...head in the sand, I guess. It's date shows 2011, 39th week and it should have the newer battery system that isn't activated until it's put into service. Thanks for the offer. Believe me, you'll see both chips in the mail soon if I run into trouble. I'm with you - rather keep the board out of the mail unless necessary. The menu instability has gone away for now. We'll see if it returns. And - I think I may have this programmer figured out after a little research and reading. Just need to know how to set everything properly. It doesn't help that the guys explaining its functions don't speak understandable English. Sorry to have taken up so much of your time. You've been very helpful. Thanks.

[CIR Engineering]