thanks for the feedback. to buy a machine that can't be shown to power up at all (in this case no PSU) and then to assume it can be fixed reasonably easily, .. is a stretch. Too much for me. I did have good luck with a Zenith Z-171 that I bought with knowledge if it would boot or not. Feel like I got lucky once. Plus, I know I would have to get an XT-CF going for this box, since almost certainly the disk will be Kaput.
IMO, I'd pass on it. It's not always just the capacitors that make them fail to power up. I got one and the caps were leaking really badly on the internal PSU, so I thought it was going to be an easy fix, just replace the caps. Replaced the caps and still nothing. Dead as can be. Have no idea what makes these Toshibas so flakey and unreliable, but from what I heard one person say, they were not even reliable back in the '90s when the machines weren't all that old. The gray AC-powered units like the T3100e are much, much better. I have never had any issues from those. But the T1100, T1200, T1000 are all crap. Shame, because they are really cool otherwise.
Now if we can figure out what's making these fail, we may be able to revive them, but until then, they are on my list of computers to avoid.
No problem! Nice you got a Z-171! Those are super cool. I have had great luck with Zenith computers. I bought an untested Z-181 several months ago and it fired right up when I plugged it in. Didn’t have to turn a screw on it (except for when I upgraded the CPU).
I'd have to disagree with you about the Toshiba's being unreliable, Toshiba produced and still do produce the most reliable and long lasting laptops. I would have to say they are equal to Compaq in design and construction, the components are always top quality and made in Japan. As for the repairing the old and fualty laptops, it is no more a gamble than repairing anything electronic that is more than 30 years old. Yes, not always the caps but 80% of the time it is the caps, the other 20% being leaking batteries, bad/corrupt CMOS/BIOS chips and bad solder joints.
You do know that some of the T1000 series will not power up or boot without a working internal battery. I've repaired a couple of T1000's and T1200's and both will not power on if the internal battery is bad. It's just a case of re-wiring the power cables on these units. From my experience the caps are the only cause of power failures on these systems.
Go have a browse at the Toshiba pages here https://oldcrap.org/ for some excellent Toshiba T1000/T1200 info.
All the info is meticulously presented with links to repair manuals, setup files, ROM's and internal photos.
The blinking red light is the battery charging circuit protection, the battery needs to be functional and chargeble along with the DC input power.
If you have missed any caps on the board then you may also get the blinking red light. You could say anything which does not power on
has a design flaw, I wouldn't say it was a flaw as it works with all the correct capacitors and batteries replaced.
I've repaired 2 units with the blinking red light and the blinking led that you are talking has other conditions in which it blinks to show
the diagnostic code. There is also an led code output on the LPT port which are all listed in the repair manual with the correct procedure
to remedy the fault. I guess that you did not use an LPT diagnostic connector on the LPT port as the blinking red led suggests there was a fault
code available and the error could be something other than the battery or power.
You see, almost all Toshiba laptops from that era had an integrated diagnostic circuit and ROM which allowed the use of a LPT dongle to diagnose
any faults with the system through the printer port (of course you'd be stuck if the LPT port failed). These dongles are easily made with just a handful
of leds and some wiring. I have used the for all sorts of diagnostics on Toshiba's and you can even reset the CMOS chip and any registered passwords.
If you are serious about repairing and restoring vintage computers, you would have one of these dongles.
I guess you were lucky to find 6 working laptops, that's not to say the non working Toshiba's had design flaws is it.
Thinking about it, you could say that all electronics from that era had design flaws when you compare them to the advancement
in electronics today
I'm only trying to point out that you may have missed something else when diagnosing the board and you may have focused all your
attention to the power supply when the fault could of been something as simple as a jumper switch or corrupt CMOS memory.
Sorry for the lenghty post, but I always like to detail my response with as much information backing up my statements rather than
What has it got to do with a Zenith center-negative plug ?
But maybe all six were repaired under warranty and/or repaired subsequently.I actually wasn't lucky at all with the Compaqs. The Compaq SLT is a very well-engineered machine.You don't just get lucky six separate times on one type of vintage computer. If you get six units all from different places and they all work, it's a damn good machine. Period.
But maybe all six were repaired under warranty and/or repaired subsequently.
Some of them have had the hard drives replaced and memory upgraded, but beyond that, they don’t appear to have had much else done to them. These machines don’t break much even at 30-plus-years of age, so I’d say it’s unlikely all 6 of mine had major failures back in the day. That’s not to say an SLT never broke, obviously anything can happen, but they aren’t trouble prone by any means.