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

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Service manual:
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
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#ElectronicsCreators #Repair #vintage

Hi, it's Vintage Computer Repair time. I've got a Bobby Dazzler for you today. It's the classic Toshiba T1000 Series This is the T1000 Le Oh, it's a thing of beauty. A joy for ever.

We're talking 1990 vintage. so we're talking 33 years old and look at this bad boy. It's got a 640 by 400. uh CGA display with blue backlighting.

Look at that blue backing on it. It just looks absolutely gorgeous. Look at it. Ah That's a thing of beauty.

A joy forever. It really is. Oh fantastic. Anyway, 80c 86r processor running at 9.54 megahertz? Yes, it was uh turbo? thank you very much.

Um, it's got one Meg of uh, memory. it's got as you uh saw on the side. three and a half inch out 720 okay floppy and it comes with a 20 meg hard drive. So this was a serious bit of Kit back in 1990.

Everyone lusted after this one. It was so in incredibly popular the Toshiba T1000 series of laptops. But what sets are the T1000 apart from the others is that this actually has dos in ROM. It's got MS-DOS 3.03 or optionally uh, MS-DOS 4 in ROM so socketed in ROM so it turns on Boom instantly.

Just like that. you didn't have to load dos from the floppies or the hard drive which took uh time and you know space as well and you're limited 20 meg hard drive. So the 1000 series both the T-1000 the T-1000 Le which we've got here and the T-1000se as well. They were all dos in ROM but this isn't the original.

uh Game Change Intoshiba. uh 1000 series. It actually started with the T1100 in 1985 which had a retail price of 1900 bucks and that was MS-DOS 2.11 and 80c88 uh processor so that you know half R star 8-bit uh, buying eight 16-bit jobby run at 4.7 and it had a smaller screen of 640 by 200. So the screen was, you know, not as high as this 1100, but in 1985 that was the world's first dos laptop you know and it was absolutely game changing.

but it didn't have DOS in ROM you had to load Uh dos from the three and a half inch floppy Drive no hard drive back then and then. In 1987 they released the T1200 which is an 80c 86 running at 9.5 megahertz. so basically the same as here and it had 20 meg hard drive but it didn't have DOS in ROM and then the same year 87 they released the original white T1000 dos in ROM But as I said, no hard drive that didn't come along until the Uh 1000 Se. but that didn't have a hard drive that didn't come along until 1990 until they released the T1000 Le if you wanted dos in ROM and that hard drive and the T-1000se came along in 1989.

Practically identical to this my with DOs in ROM but it didn't have a hard drive and as was common back in the day, you actually had a legend uh, overlay a replaceable legend for your function keys here. And this one actually came with a Word Perfect uh, 5.1 overlay. Look at that. Oh Bobby Dazzler.

Hands up if you use Wordperfect 5.1 yeah, I did. Anyway, so it's got indicators for power speed, caps lock, uh, overlay, num lock as well because it had the numerical uh keypad here. Of course you couldn't physically uh, have that separate, but this was a pretty nice layout. uh, keyboard at the time.

You know it's got the arrow keys in the arrangement that you'd find it today in home and page up, page down. and it should. You know it really is a very nice layout that you wouldn't be, uh, unfamiliar with that today. So on the side here, we have a reset hole.

Then that looks like the hard drive access. You have to unscrew that on the back here. We've got an expansion header and this one is in awesome condition. Check it out! It's very common to find these.

These Days Missing the covers and things like that because they could easily break off. But anyway, uh, expansion header. We've got Dcn. Then we've got serial and parallel.

but that's all this one did not have. uh, the internal modem. Other models I did have that. not sure if it was a retrofit for this one or not.

not sure. And if you want to see my initial uh reaction video unboxing this uh, when I got it from eBay you can find that as an exclusive over on my Odyssey Channel I'll link it down below and then we have a very nice removable battery here. Check that out so it's a Nike head. None of that nickel metal hydride at rubbish.

Uh, 2200 milliamp hour? Um, so yeah, this has gone the way of the dodo. You could possibly repack that if you could get it apart, but uh, looks fairly well. uh, sealed. But yeah, this is in fantastic condition.

Look, there's absolutely no corrosion anywhere. There's no discoloring apart from maybe a slight discoloring on that. Yes, my camera is uh, color balance. so this is very active accurate color that you're seeing here on camera.

and yeah, it just it's in really first class condition. Apart from this which I noted in my uh, unboxing video, there's a little chip on here and I did actually make that worse by rubbing it, almost as if it's like where it's painted or something. I don't know what the deal is I don't want to go any further on that. If you know, leave it in the comments down below.

and yes, I did get the original Toshiba carry bag for it. Um, and I did get some floppies as well. So if we can get this thing working now, we should be able to do something. But anyway, check it out.

Made in the United States of America So you've got to remember how groundbreaking this 1100 series was back in uh the mid, uh to late 80s. I mean really the only other competition was like the Tandy 100 which you've seen videos on and also this Tandy 200 I don't think I've done a video on this I'll leave it in the comments if you want to see a tear down. but of course this was you know the Tandy 100 and 200 with the bigger screen here was an absolute Workhorse Um, you know for any uh, journalist writer, you know anyone who goes on the road um you know this was the computer of choice. but you know once uh Toshiba released this 1000 uh series and especially like Doss in Rama booted instantly.

It was just the duck's guts. It was dos compatible and it just it was way more powerful and you know it's ah, there was just no contest. Uh yeah, the game was up. um for the Tandy uh and other uh laptops once this came out.

Anyway, this is supposed to be not working. Um and here's the power adapter that came with the 12 volts 1.7 amps. It is uh Universal voltage so I can just uh IEC uh straight in so we can actually plug this in the back and let's have a squares and confirm that it does doesn't power up what's going on? Yeah, trust me it did do something in the previous video. the unboxing video oh I have re-measured I am getting 12 volts out of that uh plug pack, but it was actually flashing.

Oh, there we go and now it is I Don't know why it didn't before. uh, it's flashing the DC in and according to the service manual, yes, you can get the service manual. uh for this I do believe that is uh, like low voltage or something like that. So possibly uh, the plug pack is, uh, dropping under load is.

However, the plug packs are Cactus or um, maybe if I simply remove. let's see if there's a load caused by the battery here. Will that fix it? Let me. Presumably, it works without the battery plugged in.

Let's just see if the battery loads it down or not. No, it seems to be seems to be doing this There we go at night flashing the same thing so it ain't the battery loading it down. Okay, we'll power it from an external power supply 1.7 amp current limit. it's drawing 80 milliamps and there's our fleshy flash.

Takes a while to come in. So and I've tried another plug pack as well and it just doesn't work so it doesn't doesn't seem to start up, doesn't do anything. So yeah, something's wrong. Ski, let's crack her open.

First of all, two screws gets that off and yep, there's the uh that looks like an additional battery interface or a uh, or possibly the motor. Yeah, yeah, the modem uh option down there. So it did actually have battery one and Battery two indicators on the front so it looks like you could actually put a second battery which isn't the same physical size as this one by the looks of it. So that's a bit of poor engineering.

Um, is it not? I Don't want? like Why? You know? if you're gonna do this, why wouldn't you like? Because well, you needed the extra modem interface. but I don't know. you could have engineered that somehow. Like obvious like the pin spacing is totally different.

So yeah, I don't know what they're thinking. there sell more accessories. I Also forgot to show you the expansion memory interface as well. So let's like you can put a card.

No, it was none of that Pcmcia rubbish and that was a custom uh Joby So I think expand up to like five Meg or something. which is pretty kick up. Anyway, if you serial number aficionados, there you go. uh, tier one system unit.

The power supply is dated uh, 1990. so yeah I believe uh, it's at least 90 vintage and there's a little uh dos speaker on it. but yeah it. I don't think it had any sort of like sound extra sound card capability.

No, that's Sound Blaster rubbish. And there's your hard drive. Check it out, it's probably still got someone's stuff on it. Um, that is a completely custom interface I Wonder what uh, type of drive it is? There's no weight in that.

Ah, all the Connor fan boys go wild. Hands up if you had a Connor back in the day made in Singapore all the best hard drives were made in Singapore Um, a CP 2024. Yeah, so I assume that's a 20 Mega jobby because that's what. uh came standard with.

it. Probably still works Okay, you know the tolerancing's in these there were, you know, fairly large. So I think like I've powered up hard drives that are, you know, 30 plus years old? No problems. Okay, you're supposed to take out these three screws and the keyboard is just supposed to lift off.

but it, uh, it doesn't. and I can't find a clip under here? don't know what's going on? Yeah, Unfortunately, even using my plastic spudger tool here. um, more of this. Yeah, it's just painted.

Um so it just flakes off. That's a real shame. It was in perfect condition. Ah, it's all starting to flake off.

Um I swear I'm not being brutal to this thing. Um, and this is supposed to just lift off. I've read the service manual and everything. Well, that was one heck of a fight.

and uh, there's the there's the damage to it. although. um, yeah, as I said, I wasn't that brutal. but I did have to be a bit more forceful.

Turns out, look, there are two plastic catches under there and I could not manipulate them like any other way. I just really had to get in there and Slide the uh spudger. But anyway, there you go. We're in there you go.

Keyboard's out and ta-da wow look at that. Toshiba custom A6 Nice. Three of them actually. Um, it is one the processor um is that our socketed ROM is that our Dos in ROM perhaps? um that looks like it's in a surface mount socket? Yes, I'm not sure which one's the processor, but anyway, um, day codes are 26 week 1990 so yeah, ladder half of 1990 build.

There's our one Meg of memory on board and there's the expansion uh, socket there. so there must be another like surface mount connector on the bottom here which you plug your card into. but there's the expansion headers over there and two 10 pin dip Parts What the heck are they? We have a power supply over here. It does have an intelligent power supply in quote marks so uh yeah, look at those.

um I like the fact that those caps they're Nippon chemicons. but I think as a matter of course. um, this is a switching Joby obviously. but as a matter of course, um yeah.

I'd be uh, sucking all those out and the good thing is you can get these out without taking the board out. You've got to assume that there's something, uh, wrong with the switch mode power supply, but uh, how it flashes that let like you know one like a supervisor in there. you know, is it? that? is it that over there? I Don't know. Anyway, what is interesting is this long battery here says a sub battery.

What's a sub battery? Um I I Don't know. It looks like they've got like multiple Um N cells in there. It looks like they've got five like end cells all in series. It's what's a sub battery.

What does that do? Oh does that? Oh, does that um like keep it in Ram or something when you do like a soft power off or something. Does that keep the ram alive? Then it boots up to its previous state and it keeps it there when you're like and you can change the batteries and stuff. I I Don't know. Well, I totally missed it.

There's the CPU down there. very unassuming. Um, but there it is. Um 80c, 86, um Dash two.

So that's actually made by Okie So there you go. Our Oaky must have. uh Intel must have licensed to Okie I Don't think I've ever seen an Okie uh, 80c or in Intel anything. Um, so anyway, that's very interesting and what we've got here.

these three are actually our Gatorade So they're not completely custom logic. They just you know and design it and then burn it into a standardized gate array. but effect. You know it becomes a custom chip, but it's not fully custom from the ground up.

Anyway, this is the I O R controller. This is the memory and bus and this one's what's called a super integration chip which uh, you know, combines all the IBM PC functionality and all the rest of it. but uh, but it is uh, decently reduced uh component count for 1990. You can see that you know like a third of the board over here is like just you know, power supply and other you know, a miscellaneous housekeeping stuff.

and yes, this is uh, confirmed to be the bias ROM so you could actually uh, change that if you wanted to and this is actually the backup SRAM So I'd say that's what this, uh, backup, uh bet this sub battery is for it's back in uh that up? yeah I can't think of anything else it's doing. and these two chips here I Couldn't see the numbers before but you can see these are actually uh, crystal oscillators. So there you go: 19 Meg and 14.7 Meg And I've done a video on my old Tandy 1000. I'll link it in if I can remember it.

it's where I designed a turbo board for the Tandy 1000 and I was basically I Believe this is for the clock. uh, the bus, uh clock and the uh cycles and stuff and you had to get the correct cycle. So anyway, I'll link in that video of how I designed that uh turbo board back in the day anyway. I Am totally suspecting these bad boys here.

so I'm gonna get that that out. Is that just stuck? Oh yeah. I think that's just stuck on there. and I'm going to get all those caps out and uh, measure them well.

Unfortunately I don't actually have a schematic for this and it doesn't have voltage test points in the Uh service manual. It's pretty good service manual, but you know it's not. Uh, it's not the duck's guts though. Anyway, let's measure some stuff here.

Three Volts. Whoop. Well, seven point. what.

Jumping between three and seven? What? Two? 1.8 1.7 What's going on Way? Whoa. Nope. Nope. This is where you've got to manually range the thing.

12 volts. Okay, that's our input. Why was it varying before you saw it? That was just nuts. Let's go back to.

Auto Range No, you saw it. That was like flickering all over the place. No, sorry. the LCD sucksy.

I think maybe I wasn't piercing the it does looks like to be a lot of oxidization on those joints. so I'm thinking that might have been it. Anyway, Um, there's our input there. So our 12 volts.

Um, by the way, the leads they can actually like they can actually briefly get it to like light up those and I hear a I hear the floppy. Kind of like trying to start up, but now there's a 5 volt rail. Okay, so that could be is that I can't read that from here, but that's uh, probably a little, uh, a 78 lo5 or something. There's an input fuse there.

Anyway, we're getting that 12 volts in. Let's see what we're getting out, shall we? Well, there's your problem. I Really need to hold those there and press the power button? Oops. No leads turned off.

Now it does that. I'm not sure what the deal is. Oh, it's cycling as leads are fishy flashing and I can hear the floppy cycling. so it's doing all sorts of weird stuff.

Wow, that's not a happy camper. See why? Is my input back to 2.73 I Said well, that's obviously not the direct input. So yeah, that's one sick puppy. I Was wondering why these caps weren't coming out easily.

Should have just been able to heat up both pads and lift. But it turns out that the, uh, there is actually a right angle. Um, the pin actually goes right angle through a hole in there. so that makes it rather annoying.

Well, you know your capacitors are kamagatsa. When in auto mode, your LCR meter can't even detect that it's a capacitor. So yeah, there's your problem even though ironically, it was a long life and uh yeah, this is actually up. Elna on a Joby Fantastic.

Um, but yeah, that one's completely coming. guts if I force it into capacitance mode. Yeah, three. Mike Um, that's supposed to be 220.

Oops. Anyway, um yeah, this one did measure low in circuit. Yes, it does have that uniquely horrible vintage solder smell. Oh wow, that is.

Oh yeah, it's something to behold. Well, that one's measuring 196. Ohms. um I I think that's a problem? Um, well, all of these Ulna ones have failed.

So all these Brown illness, um, this one is a marked as 120 mic. It's actually measuring a hundred. so I like you would just replace it as a matter of course. Um, these ones are these Rubicon Uh, Jobbies seem to be fine, but yeah, you might replace them if you need to.

So all those um, illness ones I've replaced. but I also replace the two end ones which uh, still seem to measure uh fine. what brand were they they were Rubicon uh, Jobbies. but I replaced them all.

Um, didn't have only had the one appropriate uh through-hole but uh, surface mount is just fine and dandy. Make sure I've got all the polarity correct. Um, thankfully the PCB designer has put all the positive on the top side here. so positive, positive, positive, positive, positive, positive and of course a trap Fair rate young players with SMD electrodes like this.

The black mark on the side here is actually negative. It seems obvious, but the actual mark on, say an SMD tantalum for example is actually positive. So very different. Uh, you can come at gutsa there I didn't have 120 microfarad so I've put in 100 mic but that should be just fine.

And if you just want to know um how I suspected those electrodes, Well, they're 30 plus years old. Electrolytics of course have an electrolyte. It's a wet electrolyte in there and it dries out in or it could leak out. You know, leaky caps are for example.

but just you know, 30 years, right? They can just completely dry out. And these caps, you? would? You know it's almost Universal that you would recap old uh products like this just as a matter of course. And because they were so easy to measure, didn't and you can measure them. you know, relatively okay in most circumstances.

in Circuit: I've done a video video on measuring caps in circuit I have to link that in one in and I knew that it looked like a couple of them were dodgy. So or most of all of those um Elna brand uh ones were dodgy so it took them out. and yeah, sure enough, they verified. Um, they were dodgy now I wouldn't suspect like the switching uh, transistors in here because like we're not talking about a really high-powered thing here so there's not going to be huge thermal stresses on the uh, you know, on the switching regulators and stuff.

So it's sort of like I wouldn't bother like getting this oscilloscope out to like probe switching waveforms and stuff. Um, you know, first pass is just to. you know, if you find dead electros, you replace them, then you re-power it up. and uh, before you go any further and uh, probe stuff.

So let's go. Uh, don't have the battery, don't have the hard drive. Ah. Power Power Speed.

Uh, no. Well, there's a flashing. Is it supposed to do that? Is that normal? I Don't No, Yay! There we go. Power Speed Overlay: Red Green Not sure if you're seeing that.

I'm not sure if that's normal. It doesn't seem normal not seeing anything up. Yeah, no, it's just sort of like resetting itself. Nah, the floppy is doing some seeking and but it should boot up to that dos in ROM And I'm not seeing anything on the screen.

So so we're getting diddly squat. So I'm not not liking that. That power speed thing is. let's measure the values that we actually get now across there.

five volts. That sounds good. So you're looking for five twelve. You know that that'd be our input.

Uh, what? This is our thous Big thousand Mike Jobby. Okay, two, One point. Well, ten, one, eight, eight. There's no.

okay, No, there's something something jumping around there on that. Don't like the look of that at all. That's neg. negative, negative.

Definitely don't like. The look of that negative on your cap isn't good. It's only half a volt. 1.65 No negative? 0.1 No, no, we've definitely got about 9.3 Dunno, yeah, no, we've got more power supply issues that doesn't sound right.

so I wouldn't go tracing, chasing anything processor wise or scream wise. No, that's obviously the power supplies aren't doing the business. Don I Saw something on the screen I saw something green. came on solid for a second.

I I swear there was something on the screen. Yeah, like it flickered to life so it looks like the screen is doing stuff. It looked like it had some sort of text, but the contrast could have been like way off. I don't think I'm going to be able to get that again.

What I've done is probed the backup uh, battery SRAM here figuring it should have five volts on it and check it out. It actually has seven volts on it. Ah I checked the data sheet. No, it's five volts.

Um, that's bad. Oh look, oh all those lights were on there and it just went I don't know what it did there, but it was not seven volts anymore. It's now 4.9 volts and I can measure that on say another memory over here. Oh I was getting no, that's down to 3.6 now.

Uh, it was fired before. Um and yeah. so I What? what? All right, something smells. So I'm gonna lick my finger.

use my thermal thermal camera. Hello, that's warm. Oh that's that. That's very warm.

I Don't think it should be that warm. Okay, let's get out the real thermal camera. You can see that. Uh, sure enough, the inductor there is quite warm.

That's 38. Power it up again, but there is. This is one sick puppy I Can tell you so I'm gonna quickly heat up any quicker I think it's got a that seems okay at the moment I Mean it's warm, but not not critically hot so. but I think it gets into some some well.

there we go. Did it? No, that was the camera recalibrating itself. Not yet there. We go there.

we go. It's run away. It's run away. 50.

Yep. 70. Yep. Yep.

65. Yep, it's running away. It gets into something. some sort of mode.

that, uh, transistor just uh. it's a fit because it's got a gate drain Source there and uh yeah should not get that high when it's not heat. Sun So given that that uh red DC in light wasn't coming on, manual says it's supposed to come on When you plug in the adapter, here's the adapter on the back. I've flipped up the back.

um, it was very easy. just uh undo. uh. five screws on there I got nickel screen in uh, case here and DC in Jack This goes over to here.

Aha, more electrolytics. So yeah. I Didn't expect that because there is no schematic for this thing. There is no power supply block diagram.

It just talks about like you know, checking uh, cables and you know stuff like that. Um in its uh, a DC troubleshooting? uh procedure. So yeah. well.

we've got another switching board here. So yeah, looks like we'll have to recap all those as well. They're probably Gonski are they? Elders Tell you what? I Do like the attention to detail here. it's just taking out the screws on the board and you'll note that this bit of metal uh here which is insulated they've gone to all the effort is uh, just held in with that screw and that's just bent over after assembly to, um, just keep the cables in place and they've got another one over here as well so you can just bend that um and just stops the cables getting caught when you're assembling the unit.

Very nice touch. So wow, it's another complete switching regulator in here and that is chocolate block. that's oh, it does The Uh does the battery as well. and uh, this goes over here to the Uh that'd be for the backlight.

uh for the screen I would say because that's going off into the hinge mechanism there. So and this is the cable of this is the DC output cable ones that actually goes over to the main board that we saw there. So and that's got all the indicators as well. There you go.

that's all. your indicator driver. Wow, look at that. Yeah, could be something.

Kamagats are on there. Well these caps actually measure in circuit. AK they're all uh 220 mic 25 volts. These two are in parallel here.

I have actually uh, was actually able to buzz those out and they are in parallel so that's why I was reading uh, double and you know this one reads yeah, they they read reasonable. So I don't think like you know you might want to replace them as a matter of course. but as an immediate uh haha gotcha nut. Well good luck trying to figure out how any of this uh power supply Works We've got these uh two boards here and there's a big board to board header there so that plugs in there like that and then this has its own two separate cables coming out here.

one says uh, charger and the other is lead. Okay, lead's pretty obvious I guess but uh, once. So I guess the leads are driven from. oh from this side of the board are they that seems uh, curious because there's only a Lm324 on here which is a comparator quad comparator of course and that'll that will be doing.

uh, some you know, limit voltage? uh, you know comparison and uh, stuff like that so you know if you're under voltage then that's I Don't know how they're flashing the lead because there's no triple five on there. Maybe no. I don't even have a transistor flasher I Don't think. but yeah, these two boards, they're interconnected so we've got it.

just says charge over here this uh Power connector that goes off to the power switch on the uh top of the unit. So yeah, there's the bottom of that. I've got a couple of diodes under there, a whole bunch of surface mount stuff there. and no, you cannot get a schematic for these things.

You can't even get a block diagram. And as I said, the service manual doesn't even have like typical test voltages or test procedures. There's your switching controller. It's all pretty.

uh, bog standard. Um, you know, a couple of mosfets. um here. and yes, I've measured these three caps here and they're all like absolutely bang on.

Um, like these two are in parallel. So I'm measuring 440 mic I'm measuring 220 mic here, almost bang on in circuit. so I don't even think I'd waste my time trying to. you know, look, there could be like a ripple issue or something like that, but that's you know from, you know, High ESR and or something like that, perhaps.

but no, I wouldn't like to, uh, bet anything on that at this stage. So what I'm going to go around and do is just measure uh, the mosfets. See if any of the mosfets are shorter. like just you know, check, uh, drain and sauce for example.

And then we've got the ones down here as well. and there is a apparently I didn't. The only thing I can get from the manual is that there's minus nine volts and minus 22 volt supplies in addition to the 5 volt and 12 volt suppliers. But how that all manifests itself between this switching stuff here.

this switching stuff on here which locally feeds back up its own clacker and everything and like I don't I I don't know and this is supposed to be the charger uh board So you know, like you could maybe disconnect the charger board perhaps because that's only charging the battery but you can't because that's where the DC power comes in. So the DC power comes in over to this charger board in quote marks. um but then you've got all these pins going over to here and then like how does it does that or I'd have to buzz out like all these pins on here and figure out like is this how they're getting power over to this board or is it this one here? um and obviously it's not through the lead one but is it this here? This says charger as well. So this is charger and this is charge.

So what does charge and charger mean I go like Dumb and Dumber Okay I Checked around and the only issue I could find potentially with the mosfets is this one here which is measuring 46 ohms in both directions between the uh drain and source and this one over here which was um thermally you know which was getting hot sort of like you know runaway kind of thing. It measures okay but because it like it didn't get hot instantly it's not like it was like shorted out and then you know connecting permanently connecting the inductor across uh, the rail. uh for examples hence uh, both uh, getting hot. um because it you know it seemed to like come like on like a scene to be under some sort of like software control via the gay or some sort of gate control or something.

So I don't know. My my first guess is is that is still like switching as I uh transistor. but I I don't know, it's it's just ugly the way it's all implemented well. I Suspected that there are might be components on the underside here given that all the uh, dents, you know double-sided load that we've seen on these other boards.

So after a bit of I had to disconnect all these major connectors and stuff, really a bit of a pain. it's not going to go back in too easy. but uh, sure enough, yeah, there's whoa. whoop whoop whoops, that's there.

That's some flux residue. Is it? What is that? or is that enamel? There's that enamel that's burnt off from the heating. um I don't know. But anyway, there's the back of the board and it is quite quite dense.

There's some missing memory down there. not sure what the deal is there I think I'm gonna have to get this under the tagano microscope, but is there anything else related? Oh what's you know that's looking? Oh, some of it's looking very crusty. I Don't like the look of this at all. There's a bunch of transistors down there.

Wow, they're not kidding when they say this is a smart power supply. I Really need to I can't see this on the camcorder screen I really have to get this on the big screen under the tagano I Think it seems that I have entered repair hell um I had a quick look online for you know to see if anyone's um, you know got a schematic uh for this thing or they've done um I've got my flickering issues again on my ATM I think to see if there is like a common fault or anything like that and apparently yeah, lots of people have tried to repair these. uh T-1000 um series The SE the Le and uh, the 1200 um as well. and apparently um, these are absolutely horrible and the recommendation is do Not Touch them, Do Not Buy them.

Do Not try To Repair them. Um, everyone's gone down the rabbit hole on these power supplies and nobody's really you know, some times yet just recapping it. Fix it other times no, it's these blowing mosfets. other times no I re found and repaired.

No, we had buggered traces and we had all sorts of things and nobody seemed to. you know, some people just yeah, get get lucky and get it. uh, fixed others um don't So yeah, it's not looking, it's it's not looking pretty anyway. anyway.

um yeah, if we go down here. some people have said that Q502 down here. they have suspected like um, like somebody had a faulty Q502 had a burn mark in it. but I don't see anything like that.

This looks it all looks very horrible over here for the uh, all this board because I did it all or leak on there like I have tried to clean it somewhat. but um yeah, these things were like absolutely atrocious condition. the um like the all the joints had corroded and all sorts of stuff. so pretty horrid.

Don't know what this Joby down here does. Maybe something to do with the sub battery charger? perhaps? Anyway, it doesn't seem to be anything too bad. Is there a TL uh, 1451 switcher there and it's really nicer under the microscope like this. I can't see Jack on the camcorder screen.

You don't realize how many things I miss on a little three inch camcorder screen. It's just. ah, it's just insane. Um yeah that that five volt regulator there works because you know I've measured the five volts on that uh cap just fine and this one um is like well, it measures 12 sometimes and then it measures other so I don't know.

so maybe that's controlled by this board. you know what's there's that? LMR 324 Joby there and uh yeah, so that's doing some rail comparison and stuff like that so it looks like there are some big trays. This is the Border board interconnect, but this one here. Yeah, this one here is the one.

No, no, that's the lead. Okay, no. I need the other board some just data traces on the other connector there so that's not how it's getting its power over. must be getting to some other way.

You can see the uh, glue on the bottom of the components there. There you go. That's how they do them on the double-sided They've got to glue them down so they can. they, uh, all the electrons don't fall out when it goes upside down.

Um, through the Reflow machine. But that 182 mosfet down there? That would be a 2sc 182. It all looks good. and as I said, um, these caps measure bang on so well you know, like yeah, okay, could probably desolder those as well, but nobody's pointing towards those.

everyone did Point towards the old, um, illness ones in here and that seems to be like a classic issue. All right, let's go on the bottom side here and see what's what. uh what is that NEC a1600? No idea what that is. Um, and what's going on here? Uh, is that cap leaked that doesn't look pretty? Does it? It's Trace is looking tact but oh like that's like yeah.

really ugly you can see. yeah the Caps have definitely leaked and it's got all this all this crud there. we can try and fix that. Let's get some isopropyl on there and get my good hard bristle scrubber.

But I Tried this on the other ones and it didn't come up. didn't come up that well. Let me tell you. so obviously like there could be like some corroded oh yeah, look yeah yeah.

it's definitely corroded traces there. no doubt about it. Yep, you'd have to go. Yeah, you'd have to go in there.

Yeah, look at this. Look at this. You'd have to go in there. Oh, that's almost eaten through.

Is it that's terrible? Muriel Yeah, yeah, we've got more than just failed caps here. There could be traces that are corroded away. Look at that. That's just horrible stuff.

So yeah, those caps are definitely leaked. I Mean it looks like there's some like complete breakages in there. Probably not. I I Can go in further than that.

Like, but there, it looks like it's gotten under there and it's definitely started to eat them away. So oh yeah, there's that screen flicker again. Yeah. Yep this is this is.

this is not pretty. This is not pretty at all. And look, it looks like some of the electrolyte from the capacitors has just gotten all over this like this. and there's no other way to explain that really.

that's just not. That's not just flux. Um, from the soldering. That's because it's it's not Elsewhere on the board like elsewhere.

Like go anywhere else on the board, right? And it's clean as a whistle, right? Go up here near where all the Caps were and like it's just oh, look at all that crap between the pins. this is just awful. No, I'm not I'm not liking this at all. See, this is where you start getting to the point of going well.

how desperately do I want to get this thing working again, right? So you've gotta I would now like go in there and start buzzing out all those traces that look you'd have to go in there thoroughly clean the whole board better. The nicer proper will have to get like really some heavy duty uh stuff on there and I might have to check that I didn't lift any I don't think I did. but I'd have to check where these caps came out. uh that those that they're still uh still connection through the top and the bottom? I might have to like, um you know, solder through those.

but look at all the look at all the hairy scary on there. all these joints are all just corroded. They're all just corroded. They were horrible to uh to try and desolder those caps.

By the way, trying to heat up these these corroded joints is just awful. It's just like or you know, just apply some fresh solder to them to try and like desolder them was absolutely horrible. So yeah, that that is not. that is not pretty.

So you gotta ask yourself, do I feel lucky? Well, do you punk? That's that's not pretty. That's all already showing me that I'm not really Keen to spend a lot more time on this. How different? How bad do you want it? Yeah, this is definitely going to be the end of part one. I'm not going to chase that uh, red herring down a rabbit hole like you can go like Chase these charger boards.

Let me go get it right. Here's the other uh, charger board here. and as I said, those caps actually measure um, you know, fairly decently in circuit I'm sure if I took them out, they would actually measure just fine. but yeah, like seems to be nothing wrong with that.

There's that 182 again, 177. Once again, that'd be a uh, that's a Hitachi symbol old school I Love the uh I love the package like this. Why? it's got that little um tab on the top like that and the little cut out. You know, the little Groove down in there.

It's really quite groovy. I like that package. Anyway, that's a Hitachi that'd be a 2sc um 177. Anyway, I've got a five amp fuse up there that just protects the input.

Definitely nothing wrong with that and so yeah, like you could go and try. you could go. and Chase like these two other boards. Um, but yeah, I don't know.

Look, these have been. these have been hand soldered. Oh yeah, you'd have to get that off. but without a schematic, it gets ugly to know how this intelligent power supply actually uh goes.

You know what the topology is, how it all you know interacts and and it goes together. What are the voltage, supervisor functions you know, and all sorts of stuff? So yeah, some of the stuff I was reading online like people would have the same symptom like that had the same lead flashes and things like I did but it was some other uh thing and then somebody said oh yeah, I had the same thing but I just recapped it and it worked. uh fine and others were going no no I found burnt out mosfets and I found uh, corroded traces and once again, corroded traces is is a big thing and everyone says yeah, these are just um, these are hell on Earth these Toshiba laptops. It'd be maybe a bit better if you can get the schematic, but if you do have a schematic, please leave it in the comments down below.

but I don't I don't think anyone's ever been able to get it. Um and now uh yeah, we got lucky. I took that board out and flipped it over because yeah, you can see how all those tracers are just corroded there and you go to the other parts of the board and they're They're clean as a whistle. but yeah, that's pretty sorry for those who are like the complete uh repair thing.

But no. I'm going to call it quits for a part one. Uh I Got other videos to do um until such time as I get motivation I'll just leave it here and I will come back periodically and uh, have a go. it's looking nasty.

How many hours do you want to spend on it? Many people on many Forums on many web pages have lamented the the fact that these uh Toshiba t1000s um, the power supply is just is just absolutely horrible. And then people apparently fixed all the power supplies. They got it. uh, working.

it still doesn't work. Oh, as you saw like I was getting seven volts on that SRAM chip right? Was that Elsewhere on the board? Like seven volts is five volt rated part right? Um, like maybe absolute Max six volts I have to I don't remember the absolute Max on the data sheet. but yeah, that's that's not good, right? That's not good when you get seven volts on your digital stuff. Yeah, no.

I'm not getting Good Vibes with this one. Oh, hang on. Oh hello Cracky! Duda that's a Diode I assume Oh, we've got a marking on that on that no, is it a deity looks like it I can't get quite get the part number on that. That's Kamagatsa.

It doesn't have a designator there. No, they're the two. It doesn't have a designator, but that is cracked. Well, there you go.

There's one problem, but I'm still gonna I There's still a lot of work. Oh look, another one, another one. Oh no. these are caps.

Oh wow. There you go. Didn't see that before. People are probably screaming at me.

How do I not see that one? Wow Yeah okay. that is a tent and it's gone. Ski Whoa Yeah. Look all in here.

You can see the corrode like even back this far on the board right which is a substantial differ a substantial way in right. You'd want to be buzzing out all these and checking them. It's just it's made. It's white.

Look like that. Like that's black. Is the Ace of Spades that that fear there? The joy juice has gotten in there and this is nah. this is okay.

This is getting ugly. Yeah, Anyway, there you go. So there are two caps there and is that is that another one as as well. Like you'd replace any uh tents like that as well surface mount tan.

so I'd have to look for others on the board. but geez yeah no, this ain't gonna be a simple repair that's for sure. Anyway, hope you enjoyed the journey thus far. Um, and I'll leave it at that for now and I'll work on part two as time permits.

So if you like the journey, give it a big thumbs up and leave your comments down below if you've worked on one of these um horrible Toshiba T1000s which which are great laptops back in the day, uh, notebooks. Actually, it was. Um, I believe the term notebook was coined for the T-1000 So yeah, and that's how influential these things were. looking at.

those traces going in. Uh, like even if you get it fixed like there's there's corrosion under those traces, it's under the solder mask. It's like, uh, like there's people on the forums who said yeah. I I fixed it and six months later, it was just dead.

Again, it was just dead and I couldn't you know? All right. Brand new, capped everything and I replaced mosfets and I did everything and it finally came to life. And it was just dead months later. So yeah, that's once the rot started.

It's not pretty. It's not pretty anyway. Yeah, it could be the Chongx cap I put in there. That's what I had.

It's fine. Anyway, catch you next time.

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24 thoughts on “Eevblog 1527 – toshiba t1000le dos vintage laptop repair hell”
  1. Avataaar/Circle Created with python_avatars Rodrigo Maero says:

    how about "jumping" the power soup-lies and inject the voltages directly to the motherboard inputs?

  2. Avataaar/Circle Created with python_avatars Daniel Zussman says:

    Can I pay for shipping and have a go at it?

  3. Avataaar/Circle Created with python_avatars Baba Yaga says:

    YES! YES! Screaming, "Look the cap! Look the cap!" oO

  4. Avataaar/Circle Created with python_avatars Joshua Cox says:

    Love how you said "made in a merica " lol made my morning ❤🎉😂

  5. Avataaar/Circle Created with python_avatars reace m says:

    Bit of a waste of time in all honesty. Could have at least checked some of those sketchy looking traces / put those caps in properly so they actually make contact through the board

  6. Avataaar/Circle Created with python_avatars reace m says:

    Can someone explain why this machine has a switching psu when its fed 12 dc externally?

  7. Avataaar/Circle Created with python_avatars DavidEnds 12 says:


  8. Avataaar/Circle Created with python_avatars ultracurvenl says:

    its a shame you cannot easily run in louis rossman's new "we help you to repair shop "" …
    else sent it to the coder …

  9. Avataaar/Circle Created with python_avatars says:

    ELNA crapacitors are the worst capacitors ever in older stuff.. as 12voltvideos what he thinks of ELNA stuff in old TV's and VCRs… Sony used to use a lot of them in their vcrs, repaired a video 8 deck a few years ago for a friend, every elna cap in their had leaked and ate the boards… all the nichicon were dead but hadnt leaked.

  10. Avataaar/Circle Created with python_avatars GenniDee says:

    While some old HDDs tend to be surprisingly reliable, the Conner 2.5" drives were not. They, like some of their Quantum 3.5" contemporaries, suffer from sticky rubber bumpers that glue the head stack in place so the head will not move. If yours has this problem, carefully disassemble the drive (making sure to not get the also disintegrating rubber gasket on the platters), power it on, help the head stack to unlock using your fingers and then get the data off quickly. Only a temporary fix, unfortunately.

  11. Avataaar/Circle Created with python_avatars says:

    so many memories from this! some great, some the stuff wes craven could use to make a new horror film from… I had several connor drives back in the day.. still have a 40mb somewhere and last time it was powered up (about 5 years ago it still worked!) most of them developed bad sectors galore.

    I have a box of 4mb expansion cards somewhere (like 100 of them) I got at an IT liquidation sale in the early 2000s, cant remember if they fit this or not.

    I do remember these being an utter nightmare to work on.

  12. Avataaar/Circle Created with python_avatars Sandy Nüß says:

    C520 is cracked

  13. Avataaar/Circle Created with python_avatars Gauntlet says:

    Send it to me Dave, I've got a raspberry pi project in mind 😉

  14. Avataaar/Circle Created with python_avatars 77tubuck says:

    What about printing a battery adapter on a 3D printer? Maybe it could use a lithium battery and convert the voltage with circuitry. Just a suggestion.

  15. Avataaar/Circle Created with python_avatars INT 21h; says:

    some time ago tried to repair 80286, bios battery leaked and corroded few chips and tracks. it was painful but computer started.

  16. Avataaar/Circle Created with python_avatars Paul Glick says:

    Too bad it's not worth fixing or faking all the power supply voltages externally (no documentation!). It's great theater to see you do this.

  17. Avataaar/Circle Created with python_avatars Simon Østergaard says:

    bin it

  18. Avataaar/Circle Created with python_avatars Evelyn B. Lemus says:

    It's no longer a story that the world is experiencing a global economic downturn I'm so happy that I've been receiving $32,000 from my $15,000 investments every 14 days

  19. Avataaar/Circle Created with python_avatars Sam Brown says:

    C520 looks broken?

  20. Avataaar/Circle Created with python_avatars labiadh chokri says:

    Nice video, try to power the main bord with another power supply with the adequate rail voltages

  21. Avataaar/Circle Created with python_avatars Magnus Wootton says:

    get a sierra game going on it.

  22. Avataaar/Circle Created with python_avatars lrochfort says:

    C520 on the back looks cracked in half

  23. Avataaar/Circle Created with python_avatars Ziginox says:

    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.

  24. Avataaar/Circle Created with python_avatars GadgetUK164 - Retro Gaming Repairs & Mods says:

    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…

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