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Toshiba PF picture centering

JunitoNo1 said:
Ok, so checking pin 16, the highest voltage reading I got was 3.3v, most of the time fluttering around 2.1v or so. Not so steady hands. When grounded, it did hit zero.

So, what could be the cause of that leg not getting enough juice? Would it be the resistors? Or something else?
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Can you check pins 15, 14 in a similar manner.

Pins 16, 15 ,14 are all used for the remote control board. I believe all those pins should be pulled up to 5v.


I 'think' the connection is as follows:

(Remote-41) pulled up via RA14
(Remote-40) pulled up via RA12
(Remote-39) pulled up via RA10

The resistors with the purple and gold stripe are the pull up resistors I believe. You should read ~5V on RA14, RA12, RA10 to ground.
You should also read ~5v on the MCU pins that those resistors are pulling up (MCU pin 14,15,16)
 
dewmansnk said:
Can you check pins 15, 14 in a similar manner.

Pins 16, 15 ,14 are all used for the remote control board. I believe all those pins should be pulled up to 5v.


I 'think' the connection is as follows:

(Remote-41) pulled up via RA14
(Remote-40) pulled up via RA12
(Remote-39) pulled up via RA10

The resistors with the purple and gold stripe are the pull up resistors I believe. You should read ~5V on RA14, RA12, RA10 to ground.
You should also read ~5v on the MCU pins that those resistors are pulling up (MCU pin 14,15,16)
Click to expand...
My mistake. I was measuring in AC. When checked in DC, the measurements are as such:

No remote board attatched

Pin 14: 5v
Pin 15: 5v
Pin 16: 5v
RA10: 5v
RA12: 5v
RA14: 5v

With the remote board attatched
Pin 14: 5v
Pin 15: 5v
Pin 16: 4.65v
RA10: 5v
RA12: 4.8v
RA14: 4.65v - 5v (depending on what leg im checking)
 
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Yep that all looks spot on, which is somewhat disappointing as it is indicating the issue is with the MCU itself. Not sure where else to go with troubleshooting this. One thing I will note, that when I select the 'Reset' option - I have to highlight the option, then hit the up + down + func buttons all at the same time (just mash all the buttons) for the reset to actually happen. However with an intermittent/faulty down input, not sure how it would work in your case.
 
dewmansnk said:
Yep that all looks spot on, which is somewhat disappointing as it is indicating the issue is with the MCU itself. Not sure where else to go with troubleshooting this. One thing I will note, that when I select the 'Reset' option - I have to highlight the option, then hit the up + down + func buttons all at the same time (just mash all the buttons) for the reset to actually happen. However with an intermittent/faulty down input, not sure how it would work in your case.
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Well, this sucks. I'm guessing I can't just hot swap that MCU either, right?

I've got new resistors coming in, so I was planning on swapping those in, anyways.

I may just look for a replacement chassis in the meantime.
 
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Does anyone know if that MCU has anything flashed on it? Can it just be swapped with an identical chip?
 
dewmansnk said:
https://www.arcade-projects.com/threads/toshiba-pf-d29c051-firmware-dump.17109/

The TL;DR

The MCU has a programmed ROM from the factory. There are One Time Program versions of the MCU that could in theory be programmed as a replacement. I had tried to dump the existing MCU and have not had much luck. So far we are at a dead end.
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So I'm rechecking the resistors and mcu after installing the extended remote board (which didn't correct the down issue).

The resistors 10, 12, and 14 and reading different values.

Board plugged in:
10= 5v
12= 4.88v
14= 4.65v

Possibly a resistor issue, then? If these are pull ups, then I should see 5v across all of them, right.
20210731_230423.jpg

I'm measuring from the gold strip to ground on the frame of the monitor, if that makes a difference.

I do have replacement resistors on hand, but they're slightly physically larger in size.
 
I reflowed some solder for the suspect points, but no dice.

I'm probably gonna ship the board out to someone with more expertise on this in hopes of success, and also attempt to find a spare for purchase.

I took more detailed photos of the traces. Pin 40 leads to MCU 15, which I'm reading 5v on with and without the remote board attatched.
20210806_151559.jpg
 
So I shipped the board out to someone one to get a deeper diagnosis and attempt a repair.

I've also found a replacement board, a PB9929 that I'mlooking to buy. All variants of this board are compatible with the D29C051 monitor, right? If so, will any extra cabling be needed? Or is it all plug and play?
 
JunitoNo1 said:
All variants of this board are compatible with the D29C051 monitor, right? If so, will any extra cabling be needed? Or is it all plug and play?
Click to expand...

Yes, all are compatible. It will be plug and play.
 
More questions develop.

So I sent out my chassis for recapping and a better once over by an expert. I also order a pb9229 chassis as a spare.

In the meantime while I waited, I thought to myself, I do have a display with a vga input, so I can just play on that.

So I load up Fist and I see this,
20210816_033718.jpg


The screen is shifted even here. Now, some games are loading dead center of this monitor, but others are shifted to the left, like the CRT.

So I still suspect an issue with the chassis, as I still had no control on the remote board, but this just caused me more confusion 😐
 
Good news and bad news.

Bad news first:
The board I shipped out was lost by UPS.

Good news:
I got a spare p9229 board today and it fixed all my issues.

All that remains now is to correct the colors now, but unfortunately the cabling for the remote board was lost with the shipment, so I'll have to make my own.
 

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JunitoNo1 said:
Good news and bad news.

Bad news first:
The board I shipped out was lost by UPS.

Good news:
I got a spare p9229 board today and it fixed all my issues.

All that remains now is to correct the colors now, but unfortunately the cabling for the remote board was lost with the shipment, so I'll have to make my own.
Click to expand...
Crazy update!

After a solid year from the last posting, I just got a call from Sharp Image Repair in Vegas notifying me that my chassis has been repaired and is ready to ship back to me. After 11 months of being lost, the package somehow found its way back into transit and landed on SIR doorstep at the beginning of this month.

WOW.

So, the issue was a culmination of cold solder joints, failing resistors, and (primarily) a faulty MCU. With all that repaired/replaced and new caps installed, the chassis is ready to go.
 
JunitoNo1 said:
Crazy update!

So, the issue was a culmination of cold solder joints, failing resistors, and (primarily) a faulty MCU. With all that repaired/replaced and new caps installed, the chassis is ready to go.
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Hi! :)

they changed the MCU =O ?

Do you know which resistances have been changed ?

Because it can give me a clue for mine which still has its problem of setting memory ;(

Thanks ;)
 
chacal231077 said:
Hi! :)

they changed the MCU =O ?

Do you know which resistances have been changed ?

Because it can give me a clue for mine which still has its problem of setting memory ;(

Thanks ;)
Click to expand...
Yea, told me they swapped in a spare for the MCU, and the resistors that were changed were RA11-RA15, possibly some more besides those.

You can change settings, but are those changes not saved between power cycles?
 
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