EEVblog 1527 - Toshiba T1000LE DOS Vintage Laptop Repair HELL

This Ebay Toshiba T1000LE vintage DOS In ROM laptop repair turned out looking promising until, well, it didn't...


00:00 - THE laptop that cointed the term Notebook, the Toshiba T1000 series
05:46 - It obsoleted the Tandy 100 and Tandy 200
07:00 - Powering up
10:16 - Opening up had a few issues - OOPS
12:12 - The first suspect
17:55 - Bad caps?
20:50 - Suspect process
23:18 - Backup battery SRAM problem
24:12 - Thermal camera
26:32 - Extra sneaky PSU
33:27 - Under the microscope, this looks BAD!
37:00 - Yuck!
44:28 - BUSTED

Other channels:

#ElectronicsCreators #Repair #vintage

[GadgetUK]

These old Toshibas are shockingly bad - both in layout / design and the caps and trace thickness on PSU section. I started looking at a T1200 (yet to revisit with microscope soon) and I spent hours messing around trying to get the PSU section up and running properly. I suspect I may not be able to fix it... Considering how old it is, I was shocked at the trace and via size on the T1200 PSU board (it has just one separate PSU board unlike the T1000). I can hardly see them with magnification...

[michaelcalvin]

45:06 - "People are probably screamin' at me!"
I was one of those people xD
I had planned on letting you know about the cracked caps (which I had thought were diodes) if you didn't notice them before the end of the video.

[CSTRSK]

On the Back side is a physical broken diode or some thing.
C517 below the coil between C520 and C521 40:45 found at 45:01 😅

[ernstoud]

I was product manager with Toshiba in The Netherlands from 1989 until 1994. Interesting times. So many revolutionary inventions; small harddisks, pcmcia, first color TFT (T4400 series), hefty competition with Compaq, dramatic price drops etc.
The sub battery is for “AutoResume”, i.e. instant power on, remember that MS-DOS had no support for standby.

[thowij]

I have a couple of these machines as well as a T1200, T1000 and a couple of T1000XE's.
It's a love-hate relationship. I love the look&feel and the history behind them but every single one you get has the same problem.
The Elna and NipponChemicon caps used in the DC-DC converters all just start leaking from the bottom and the electrolyte does the rest.
No way to judge it from the outside of the machine or even from the top of the board.
On top of that, what looks like minor damage may lead you down a very, very deep rabbit hole.

I've fixed all 3 of my T1000LE's and they still work after a couple of years.
In the mean time I've fixed, amongst others, two T1600 and reverse-engineered the PSU PCB's for them along the way.

Feel free to send me a message if you need any information or just want to exchange thoughts (see my YT community or about page).
I have 3 of these to check component values, etc. if need be.

I've spent countless hours searching the web and staring at these boards so I'd like to think I know a thing or two about them.

[ziginox]

The sub battery is a feature that laptops had up until the late Pentium days. You could put the machine in standby, then yoink the main battery and swap in a fresh one. The sub battery (called standby battery in other machines) would keep the RAM refreshed for the short time needed to swap main batteries out. They also sometimes keep the CMOS settings, but it's not uncommon for a computer to have a separate battery just for that.

[dombaker]

I had a T1100, and a T1200. The keyboard was lovely to use. The thing I remember the most was the smell that had something really special about it as it reminded me of the happy first contact with computers.

[sarah]

I'm also noticing under the marking R513 that there is another black component that has a decent crack through it as well

[johnsonlam]

Definite need to add jumpers, lot of work! C520 broken, if someone got a good one, please help to check the value.

[billpeiman]

I have incorporated OKI 80C55-2 and 80C88 in our products for 30 years; still use them today.

[jamesking]

Dave, C520 (large black SMD cap) on the underside looks like it has a large crack through it.

[anfa]

Regarding copper traces, use a thin tin-plated copper wire and solder it from point a, bend the wire along the trace, solder the wire in the trace towards point b. It will be nice that way.

[IanScottJohnston]

It's worth the time to repair for YT, always great to see a nice juicy repair.
PS. if you want to see a rabbit hole check my Keithley 2001 DMM vids. I needed a holiday afterwards!

[MartinE]

We had several hundred T1100+ dual floppy laptops for field engineer use in the late 1980’s, near zero failures of the units themselves but the mains to dc power supplies from Toshiba were notoriously bad, running hot and with thermal fuse failures. We gave up on Toshiba replacements and eventually designed and manufactured a new one in house.

[OneBiOzZ]

rip it all out and put a pi in there. Figuring out the keyboard might be a pain but it can probably just be wired to a USB keyboard controller directly. The display might need to be replaced if you dont want to go down the rabbit hole of figuring the display out
Might make a nice serial terminal

[hans]

T1000? Conner drive? Dude ya wasted perfectly good Terminator joks

[NikiBretschneider]

There is a lot of corrosion caused by leaked capacitors, which is pretty typical for caps from that era, especially if they are "high quality" brands. They leak out instead of drying out, so if they are not replaced (or removed) before they definitely fails, they cause a huge mess of electrolyte, corrosion and similar things on the PCB, which is typically non reparable issue. I prefer capacitors that dry out instead of leaking, which are typically the cheap ones. They are more often to fail, but also much easier to repair. In my opinion, that leakage caused a short between the windings of that big inductor (L501 or what), so I think this one should be at least rewound. Next thing are that broken SMT capacitors, which is in my opinion caused by slightly higher voltage like >7V on the 5V line (that capacitors are typically 6.3V), which, if occurred (and we know this happened), fried almost all TTL logic, so I think this device is completely nonrepairable. Which is something very typical for these old toshiba laptops.

And well, plastic housing of these devices was painted. It was a huge pain in the ass past then, because almost every repair resulted into some minor paint rip offs caused by bending or stretching that housing. Plastics are flexible, but the paint is not. That was a terrible idea, but, well, this was how things was made past then.

[KeritechElectronics]

T1000LE? A mimetic poly-alloy. None of that living tissue over a metal endoskeleton rubbish.
(I'm sorry Dave, I'm afraid I really had to drop some pop-culture references - but Dirty Harry is yours)
And hmm, seeing a Conner disk in a T-1000? Can't be a coincidence!

Lovely old laptop - shows how far we've gone since WayBackWhen! I hacked with some late '90s Toshiba Satellite, and a Thinkpad 380ED, but nothing that old.
Oh the mobo, a thing of beauty and a joy for ever. Too much rosin leftover for my taste though.
Unassuming CPU indeed. Who would have thought?
14:54 these xtals in a DIP package are a fascinating thing in itself, now that I've seen that in the Open Circuits book.
Electrolytic come-a-gutser, as always - what else would you expect? I would still bend the leads and put them through holes for extra mechanical rigidity.
Extreme discombobulation going on there on the backside! I wonder where this corrosion (hey now, hey now, now...) came from. Catch you later with this laptop, I hope! I'd love to see the launch.

[jamesmauer]

I waited to the end to see if you saw those cracked caps! Good luck with this one!

[changeagent]

I love remembering all the old systems I grew up with but I don't miss how slow everything was. 😄