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Toshiba T1200 schematic

Yes I'm afraid I'll have to source a mainboard as well

I've really done EXTENSIVE research , but because of really minimal NiCD leaks on top of the bus controller, it seems some tracks are either shorted or behave completely wrong, I also believe part of the problem is UNDER those smds, and I think it's hopeless (but see below)

The board looks clean visually, but even after multiple washes, there is something wrong in something that can't be seen even with my microscope.

Some tracks look more green than gold (under the varnish), which doesn't seem right.
It's really a vicious fault, that really can't be seen, but it's dead (reports "NO KEYBOARD" error all the time, frustrating because apart from that it boots and works...).
But no keyboard :(

I'm giving up.

I will keep it for parts,
 
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Another question is

Now that toshiba is officially defunct,

Is there really no way to source technical doc from them/former employees or something ?

In order for us entusiasts to keep their systems alive, we really would need schematic of their vintage systems, and I don't see why they couldn't share that info after 40 years for systems like 8088 laptops :(
If we don't put our hands on schematics now, they'll more than likely be lost forever (if not already the case)

Is there anyone who would be able to contact some former employee, or technician, or anyone that could maybe help raise the issue to whoever now owns the intellectual property of former toshiba ?

On my side, I've just emailed some press person at Dynabook.

I could probably fix my T1100 motherboard if I had a T1100 schematic. Same for that other guys with his T1200 problem.
T3200 would also be nice.
Anything below Pentium for example...
 
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Have you tried an external keyboard or another keyboard cable ?
As for the schematics, you'd have trouble getting them for most modern laptops. All the design sheets and schematics for your T1200 will
be long gone and destroyed along with the systems they were designed on. Why would Toshiba bother archiving them and then making
them available for free for anyone who asked. There are probably only a dozen or so people who actually own a T1200 now.
It's not that difficult to reverse engineer the circuit yourself, but it's also no fun task. The problem is not having the schematics, it's
not having the discontinued components and IC's. Toshiba used their own Microcontroller ic's for the power management and
controllers which communicate with the BIOS and ROM.

All I can suggest is do more checks around the board with your meter. From my experience you will fix one fault only to find more
and more faults will eventually surface.
 
Regarding the schematics, I think that Toshiba beeing Japanese (especially those vintage models) there is no doubt their document management is flawless and that these schematics are easy to find if someone with the rights credentials starts to look for them, for us, vintage afficionados.

I don't see a reason why they wouldn't, the problem is really finding an insider to start with.
I got no answer back from Toshiba America PR contact, which is no surprise, I would have preferred that they at least answer with a "no".
I believe it would be much easier going thru a former employee that probably has a copy of old things rotting in a drawer.

Regarding the repair process you are absolutely right, most repairs end up finding multiple problems, I keep telling that to people who want me to fix their old Sega Genesis or Lynx because I have the right equipment... They seem to believe everything is as simple as in youtube videos, that I'll desolder two capacitors and it'll magically work again, that's not how it works as most of us know (and few youtubers show.)

Caring about vintage laptops is even more difficult (I think) for the reason you stated, heavy use of customs ICs and single ICs doing a lot of things.

I'll continue to harass Toshiba or their affiliated companies :)
 
Caring about vintage laptops is even more difficult (I think) for the reason you stated, heavy use of customs ICs and single ICs doing a lot of things.

I'll continue to harass Toshiba or their affiliated companies :)

Well even with the schematics for the power and logic boards, you are going to have a very tough time finding replacement screens for these kind of laptops.
The screens are not easily repaired, the power boards can be bypassed and re-wired quite easily. I've decided to retro fit more modern boards and easily available
VGA panels from old monitors into some of older laptops that I have. Most of the screens I replace the invertor and failing tubes with LED strips. For the boards I use
those mini AIO dos systems and custom wire all the ports to the original ports. This way I get to use a more modern reliable system in the original retro case.
The old laptop cases are huge in comparison to the AIO boards with lots of space left for the Arduino PS2 keyboard controllers which I use to interface the old ribbon
cables from the original keyboard. Looks messy with all the re-wiring but with the case closed it looks real nice. The T1200 has a very nice ALPS keyboard and
is great to use. Unfortunately I don't have the pleasure of the blue on white screen anymore, so the 256 colour TFT panel I retro fitted will have to do for now :)

You can pick the AIO dos system boards from a great seller in germany on ebay:
https://www.ebay.co.uk/itm/17-43CM-TFT-with-Integrated-1000MHz-Computer-Mini-PC-Silent-12V-NT-Ms-dos-M1/312576885910

I will probably post a topic with some photos later this year when I can recover from all the binge drinking from last year :)
 
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I'm sorry for bumping an old thread - but I've recently picked up a T1200 with a broken power-supply.

The previous owner attempted a repair himself and removed a few caps - before realising the repair was beyond his tools and ability. Unfortunately, this has left me without knowing the values of capacitors I need to fit in their place. I have noted someone in this thread mentioned the value of the two SMD tantalums - but no mention of the other capacitors.

I'm hoping someone might have recorded the values of each of the capacitors, so I can source and fit the correct parts.
 
I'm sorry for bumping an old thread - but I've recently picked up a T1200 with a broken power-supply.

The previous owner attempted a repair himself and removed a few caps - before realising the repair was beyond his tools and ability. Unfortunately, this has left me without knowing the values of capacitors I need to fit in their place. I have noted someone in this thread mentioned the value of the two SMD tantalums - but no mention of the other capacitors.

I'm hoping someone might have recorded the values of each of the capacitors, so I can source and fit the correct parts.
C1-1800uf 10v
C2-1800uf 10v
C3-470uf 25v
C4-150uf 35v
C5-470uf 25v
C6-10uf 25v
C7-470uf 25v
?C8?-220uf 25v (one between C4 and C7)
 

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Ah! Excellent. I can get those caps ordered without even opening mine up.
I just received my uncle's old T1200 that he used in college (and I used in high school for a short bit in the mid 00's since I was fascinated with old computers at the time) and it almost powers up, screen flashes, lights go, it tries and then fails (it was working fine about 5 years ago, last time it was powered up, so I thought nothing about plugging it in and turning it on). Going to start with the caps and internal batteries and go from there.
 
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