Just came to inform you guys, that I've completed DUNE (1992) on Siemens Nixdorf SCENIC Mobile 710. I'm not just collecting old junk, I'm also playing games I've missed in my youth. Dune worked like charm, but I've missed that there was CD version and since saves are incompatible I've stayed on floppy one. Wave Table Synth worked well, but on Morning song it produced some ring-bell sound instead of proper music instrument. Will recheck it on CD version and publish video bout it.

On my Toshiba T4700CT I found some utility called ultra.com with it I was able to stretch nc and other general dos stuff:

But then I’ve tried doom and it is squeezed like before 🙁 any way to extended ability of this tool to other dos apps?

On yer basic VGA CRT in 1993, no digital controls or setting memories, Doom would be just like that anyway.

Friends, I need some help. Got old no name laptop, model 8700T, ID: L4PK8000X15, made in Taiwan by Kapok Computer Co. Power supply is missing, power connector is really strange, 4 pins, maybe 20V and battery charging, not sure. Here is how it looks like, any idea how to power it?

I feel like it looks a lot like certain old Dell chargers? I can take a look when I get home, pretty sure I have one.

LHN91 wrote on 2021-09-07, 15:31:

I feel like it looks a lot like certain old Dell chargers? I can take a look when I get home, pretty sure I have one.

Thank you in advance!
So, after some external charge battery got enough juice even to boot and work 20 minutes. Laptop booted in Win XP, now I know why someone in Germany changed the CPU to K6-2 400MHz(running at 333MHz), 256MB RAM and 10GB HDD.
After the battery died I connected a powerful 12V PS direct to bat pins and even managed to install Win 98 SE. The bad news are that some keys do not work and the sound is too weak for some reason.

I've got that laptop's relative, the 6200AT 😀

If parts of the keyboard aren't working, you could take it apart and repair the traces? I've done that to resurrect 2 laptop keyboards now. It does require patience and a temperature controlled soldering iron if there's just plastic holding the keyboard together, rather than screws.

There's another similar one to your laptop here, which has the pinout but it's not quite correct: http://oldcomputer.info/portables/ca6100/index.htm
The charger for these laptops is a bit strange, it has 2 sets of voltages. The upper pins handle charging, the lower 2 pins are for powering the laptop. Which from what I recall has the battery charger part in the PSU.
I'll have to dig out my charger again but it's so bulky I made my own barrel jack adapter and put the original PSU. I use a bench PSU instead, that way I can see what the power draw is and it fits everything.
[there was a picture here, looking at closeups, the pinout numbers aren't right]
Pin 2 on there is 18 or 19v on my PSU and that's what I usually run it at, but 12v is fine according to the website
Pin 1 is ground
If you've got any broken LCDs, the inverter connector is a direct fit 😀

DundyTheCroc wrote on 2021-09-07, 18:13:

Thank you in advance! So, after some external charge battery got enough juice even to boot and work 20 minutes. Laptop booted in […]
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LHN91 wrote on 2021-09-07, 15:31:

I feel like it looks a lot like certain old Dell chargers? I can take a look when I get home, pretty sure I have one.

Thank you in advance!
So, after some external charge battery got enough juice even to boot and work 20 minutes. Laptop booted in Win XP, now I know why someone in Germany changed the CPU to K6-2 400MHz(running at 333MHz), 256MB RAM and 10GB HDD.
After the battery died I connected a powerful 12V PS direct to bat pins and even managed to install Win 98 SE. The bad news are that some keys do not work and the sound is too weak for some reason.
win98.jpg

Unfortunately the old Dell is similarly shaped, but it's a 3-pin not a 4-pin connector, sorry.

Thanks, Thermalwrong, I have a lot of broken LCDs, hope to find connector.
Keyboard fixed, just bad connection. Left battery capacity i about 5000mAh, not so bad for 24 years old cells. BIOS battery is dead, have to desolder it.
Inside there are some clues left, actually K6-2 runs at 300MHz (66x4.5).

Performance is not so bad too:

The sticker was in there with the dip switch settings? awesome 😀 Oh yeah, that battery is a 'VL' rechargeable lithium, it should charge up once the laptop is powered for a while. A CR2032 isn't safe to put in its place.
That's great news about the keyboard too, those take quite a lot of work to repair.

I dug out the charger, here's what it says on it:

It uses an IEC13 kettle plug rather than the smaller cloverleaf type. Ironically I have 2 of them now and use neither.
I got the 2nd one with a different plug type with another 90's taiwanese laptop for cheap, though sadly the laptop was destroyed by battery leakage. It uses a different type of connector though, still with 4 pins but one of those round metal shielded connectors with 4 big pins, like external hard drives and things used to have.

And here's my adapter, the inverter plug fits on there pretty securely by itself, but the 'polymorph' thermoplastic stuff is on there to hold all the wires in place and stop it being plugged in upside down:

Thanks for the warning, I did measure battery before turning laptop on an it was 0 volts, but now is 2.5V without power and 3.3V when working, it keeps some charge.
That is the charger, model AC-D01, found a picture of it in old FCC tests. Here is some info about Kapok laptops (manuals, block diagrams, pics, etc.):
https://fccid.io/L4P
Can you measure voltage between pins, please.

huh, I can do even better than that, I dismantled the power supply back when I was making this adapter and took these notes:
Voltages:
pin 1 - ground
pin 2 - 20v - black wire, labelled Vo
pin 3 - 20v - red wire, labelled Vc
pin 4 - 20v - white wire, labelled F-B. Could it be Feed-Back???

Vc links to R52, which goes onto the positive side of the Charge LED, so yes it's definitely the charge pin.
Oh also its track is smaller and goes into a component marked Dxx, a big diode? it was a big black component that looked about the size of a large ferrite bead (in PCB terms) and yes I would expect the charge output pin to go through a diode so that current can't feed back in to the power supply through this charge pin.

Resistances:
pin 2 > 3 = 90k
pin 2 > 4 = 90k
pin 3 > 4 = 2k

Also before I put the PSU away, lets look at the pinout of that connector close up - the labels are a little different and these measurements match this new picture:

Thanks again, the labels on the last pic are just the same with that on laptop connector.
After work I will try how it works or how the white smoke is going out 😀
p.s. No white smoke for now, here are some experiments:
1. External PS connected instead of battery, 12V and 1.66A at idle, power about 20W.

2. External PS connected instead of battery, 12V and 2.47A at load (Everest stability test), power about 29-30W.

3. Connector from HP DJ 7000 printer, after some cuts fits perfect on pins 1&2

4. Battery inserted, external PS connected to pins 1&2, 19V and 1.08A, 20-21W at idle.

5. Battery inserted, external PS connected to pins 1&2, 19V and 1.64A, 31W at load.

When laptop is off battery diode lights in red, but no charge is going according to ampere meter.
Thanks again for the help, next step is to make a charger.

Can you tell us what so special about this lappy?)

I like Kapok laptops quite a bit 😁 They're weird, their history is confusing and they were rebranded as all sorts, so they aren't recognised as collectible like IBM / Compaq laptops are.
So they sell for a pittance when you find them. A lot of them have TFT screens and that integrated ESS wavetable too.
But perhaps we could have made a separate thread, I think it fits here fine though.

Nothing special, just took it for desktop replacement. My son likes to play some DOS games from time to time, but his DEC Venturis 575 takes a lot of space on his desk.
As Thermalwrong said, Kapok are interesting part of laptop history and they are not so bad at all. It is retro laptop thread, is there any problem I posted here?

Wow wow, they can have native dos general midi music?

Audio system is ES1879S+ES692S, ES692S datasheet says:
ES692 supports General MIDI, providing for 128 melodic instruments with the ability to play back 32 voices of 16-bit data at a sampling rate of 44.1 kHz.
Wavetable ROM is 1MB.

Thermalwrong wrote on 2021-09-09, 23:19:

I like Kapok laptops quite a bit 😁 They're weird, their history is confusing and they were rebranded as all sorts, so they aren't recognised as collectible like IBM / Compaq laptops are.
So they sell for a pittance when you find them. A lot of them have TFT screens and that integrated ESS wavetable too.
But perhaps we could have made a separate thread, I think it fits here fine though.

Kapok is a Clevo subsidiary, right? Their machines end up as ODM rebadges under different brands?

bjwil1991 wrote on 2021-06-09, 06:10:

Here's an almost perfect laptop. […]
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Here's an almost perfect laptop.

It's an IIT Wedge Showman DS/DV with a Cyrix Cx5x86-100 CPU (standard Socket 1 LIF), 16MB RAM, C&T video, ES488, Trackball, 640x480 TFT Active with a projector mode (removal of the top display cover door and installing a side cooling fan), functional floppy drive, and boots to Windows 95 (must've had Windows 3.1 with DOS 6.22 back when it was new in the mid 1990's).

The downside is the stretched display and I'm unable to find an option in the BIOS setting to disable it or the VGA utilities since the diskette it has doesn't have the files (must be a disk 2 somewhere).

It needs the hinge repair and a couple of other items, but it's almost perfect for DOS gaming.

IMG_20210609_005958448.jpg

IMG_20210609_012338452_HDR~2.jpg

There might be a solution. Try VEXP for Toshiba, if Your C&T chipset is compatible You can hack a thing or two with this util. There is exe and txt as instruction attached.