Watch on YouTube: https://www.youtube.com/watch?v=FtghCWxF4eA
What’s Inside This Chunky Piece Of Computing History?
Introduction
This RM branded 286 laptop is a real piece of computing history! But what’s inside… and does it even still work?
Script
This rather neat little device you see on the desk in front of me is an RM NB200 laptop from 1983. Now, if you are a British person of a certain age, you’ll no doubt have fond memories of RM or Research Machines as a brand.
Founded back in 1973 in Oxford, they’re perhaps best known for their 380Z CP/M machines from the late seventies, and of course, the iconic Nimbus from the eighties, which many of us - myself included - remember using in our primary schools way back in the day - and is noteworthy for the fact that it was one of the only consumer PCs to use Intel’s 80186 CPU.
So there you go! Fascinating RM fact there. But unlike the 380Z and the Nimbus, this wasn’t actually made in-house by RM - No, you see, this is actually a rebranded Siemens Nixdorf PCD-2N, and was also sold under the ICL, Packard Bell, and Targa brands according to thenimbus.co.uk, which is where I sourced a lot of the information that I’m going to be imparting upon you in this video - so thank you ever so much for putting that out there - and of course, I’ll put a link to that down in the description so you can check out that website at your leisure.
With that in mind, you would think it would be easy enough to find information on this specific machine, but unfortunately, apart from the aforementioned website, I haven’t really been able to find much at all.
For example, I can see that it uses some kind of strange 3-pin power connector, and thanks to thenimbus.co.uk, I can see that it’s some kind of unusual dual voltage setup, but I haven’t been able to find the pinout - so of course I don’t want to go plugging stuff into this willy-nilly in case I blow it up.
Then of course there’s the question of the specs: is it a 286? Is it a 386? How much RAM does it have installed? What’s the hard drive capacity? Does it have the optional co-processor? I have absolutely no idea whatsoever - so I thought for this video, what we would do is take a look around the outside of this thing and see what it’s all about, tear it down and find out what’s inside it, and hopefully try to work out how to get some kind of power hooked up to it and get it actually fired up - so let’s get on with it!
Right, now, just before we get stuck into this hardware, let’s have a look around the outside and see what we can see.
So first up, if I open up the lid, we can see that this has a pretty sizable screen for a machine of its age - but there is a twist here! You see, according to thenimbus.co.uk once more, this is a 640x480 monochrome display - so I’d be very interested to see this up and running because this should be super, super sharp.
Of course this doesn’t have a sound card or any kind of pointing device, so no trackpoint or touchpad or anything like that. No speakers either, but what it does have is a rather nice keyboard: there’s some really nice travel to these keys, they’re really nice and tactile and quite clicky as well - I was quite impressed with this keyboard, and again, I would be very keen to try this out and do some actual typing on it.
On the back, we have that 3-pin dual voltage power connector that I mentioned before, an external floppy drive connector - which is quite interesting because this machine does have an internal 3.5” floppy drive - a parallel port, a serial port, and some kind of proprietary expansion connector, presumably for some kind of dock - and unfortunately, this is the one protective flap that is missing from this system. But hey, the others are all here and they’re all intact and they all click into place quite nicely as well - so, hey, I guess we can overlook that one.
On the right hand side we have that 3.5” floppy drive - not quite sure if this is double density or high density, whether it’s 720K or 1.44MB - we’ll try to have a look at the model number once we get inside this thing.
We have the power switch, of course, as you might expect, and also two PS/2 ports, which would traditionally be used for an external keyboard and mouse of course - and the thing that amused me about this is that the keyboard port is actually labeled “Key Pad” - so I guess they intended for you to use that internal, very high quality keyboard and just have an external numeric keypad perhaps to the right hand side of this machine. I’m not quite sure if that was offered as an official option - I will have a peruse of the internet and see if I can track anything down.
On the left hand side there is another pretty much identical flap, and this has a VGA connector on it, which is labeled “CRT”, which again, I think is quite quaint and quite amusing - and also we have a panel here which hasn’t been punched out, so this implies that maybe this was an optional extra on these machines, and that one is labeled “Line” and “Phone” - so perhaps an option for some kind of internal modem - how intriguing!
…and just behind that is another flap, which hides perhaps this laptop’s greatest feature, and this is probably one of the biggest and heaviest laptop batteries I’ve come across in my many years of doing this: it’s Sanyo branded, It’s 4.8 volts, 5,000mAh, and this is an absolute unit. It’s a NiCD battery. I’m not even sure how I would go about trying to charge this thing or whether that would be a wise decision, and indeed, I haven’t been able to find a direct replacement for this either - so I’m going to have to come up with some kind of alternative power solution.
So let’s get this torn down, shall we? And I have absolutely no idea how I’m going to tackle this, but it looks like all of the screws that I can see are just standard Phillips screws - so hopefully that bodes quite well. Of course, these older machines being, kind of bigger and less complicated than their modern counterparts, I think that goes without saying - and that’s just a single Phillips screw in the bottom there.
Right! Okay. Let’s see what we can find - and take the screws out, I guess.
Right, so there’s a strip above the keyboard here, and if I just very gently tease this out, we have two more screws under there - so I guess they’re next…
…and we can already see something interesting here - look at this! This is the RAM.
Okay, well I’ll leave that there for now. There’s something else here as well - I think this might be the BIOS? Interesting stuff - and there is a ribbon cable, so I will just grab my tweezers…
…I’ll just ease this one out - the ribbon cable for the screen.
So that’s another one of those ribbon cables for the keyboard.
Uh huh….
Lovely keyboard - and here we can see some more interesting gubbins - so, more batteries here. I’m assuming this is for the BIOS, but yeah, it seems quite substantial. It says 4.8 volts, 1200mAh - I guess I’m going to have to find a replacement for that - they look like standard AA NiCD cells in there so I guess that’s not too much of an issue. I’m thinking this is the hard drive in here - and this quite obviously is the floppy drive. It looks like they’re just held in by one screw in the middle - so let’s get that one out.
Ah, so the connectors for those are actually underneath this part so I guess I’m going to have to get this whole screen assembly off next.
Okay. Very nice - so it looks like this is the power cable for the backlight, for the screen. I think pink and white are pretty standard for those, so I’ll just unplug that - and this other connector here actually comes directly from the battery - so we have a red and a black connector here - red and black wires.
So that’s looking quite hopeful for our mission to power this thing externally, of course, we have the black wire there and the red wire there - our negative and positive from the battery. That’s a 4.8 volt battery - so I guess if I hook up some kind of 5V external power supply, maybe we’ll be able to get some life out of this thing.
That’s detached there - and I think I’ll leave the screen assembly as it is - there are some more screws and things in there, but I don’t really need to disturb that because what we are interested in is the actual motherboard itself, which we now have a very clear view of, so let’s remove this battery, get that out the way, and perhaps zoom in a bit closer on this.
Okay, so let’s get a bit of a closer look at this and see what we can see - so let’s remove these RAM modules first because they look really interesting - I haven’t actually seen RAM like this before. I think these are SIPP modules are they? I’ve read about these and I think I have seen them in one other system, but yeah, this is much older than the stuff that I usually work on.
We have- these are 256K chips here and we have eight on this board and eight on the other - so 16 in total, which is going to make for… Of course they’re kilobits…
So that’s what, 2MB of RAM in total, something like that - which is probably about right. Probably indicative of a 286 system. I’ve never seen modules like this before - these are really cool! Very cool indeed.
…and it looks like, yeah! Wow - so - yeah, that’s the BIOS chip which apparently is also removable for some reason. It just slots in next to the RAM, so that’s quite interesting. That’s just a standard EPROM chip on there. What a nice little module that is - and of course, this is all accessible without having to strip it down this far - we could have just taken that top flap off and just upgraded the RAM that way, which is very nice, a very nice accessible design.
What else can I see in here? This is a Dallas realtime clock chip - so this actually saves the system time, the time of day, and if you’ve not come across one of these before, it actually has a clock chip and a battery inside it as well, which will more than likely also be dead, I think - that’s a bit unusual with that separate CMOS battery as well, I’m not quite sure. Maybe that was not a Dallas chip? I’m not quite sure. I’ll have to have a closer look at that…
…ah, yes it is. A Dallas DS1287 realtime clock chip - so yet another battery in this system.
It looks like this board handles power-related duties - so we’ve got the power switch itself just there, the power connector, the connector for the battery, for that CMOS battery as well - and of course the output for the backlight. Look at that! Wow, look at those bodge wires!
They’re evidently carrying some current across that board there. They’re really cool. Really cool to see that - and a bit of glue as well - a bit of hot glue holding it all together, I wouldn’t expect any less.
…and this is our floppy drive, so that’s a Sony MPF220-01 - there’s the label on the bottom of that. Let’s just do a very quick Google of that - and yeah, apparently that is a 1.44MB floppy drive and it’s a Sony as well, so that’s nice. Quite a high quality drive, I bet that probably still works - that’d be nice, wouldn’t it?
…and this is our hard drive. How interesting! I’m going to have to be very, very careful with this ribbon cable here because this looks quite fragile.
How interesting…
Ha! Look at that! That’s really cool - a Conner Peripherals CP2024.
I don’t think I can really glean anything from that information there - there’s no capacity printed on there or anything like that. Again - let’s consult Google.
20MB, I think? It looks like that might be a 20MB 2.5” drive.
That is so cool.
Look at it! It’s so thick! It’s a chunky boy!
…and finally, the main event - our motherboard here. Look at this. It’s kind of quite complex and yet quite beautifully simple all at once, isn’t it? Yeah, it’s really nice design that is.
This is our CPU here - so it is indeed a 286, manufactured by Harris - and we have the slot for that co-processor here - this was marked on the bottom as- you know, it had a marking to indicate as to whether the optional co-processor was installed - and it looks like this slot is empty, so I believe this is for a 287 math co-processor - I think I have some of those, actually, I’ll have to see if I can find one and slot one into that slot.
Of course, the Dallas realtime clock chip as previously mentioned, we’ve got this internal speaker here, which I guess is probably just a beeper. Yeah, so we’ve got that Cirrus Logic BIOS.
I’m not quite sure what are these?
Chips F82C601 - I think this is the VGA controller, but I can’t seem to find much information on that one.
Ah, interesting - so this is a Headland HT21 chipset used in this laptop, which isn’t one that I’ve come across before - and apparently a company that doesn’t even exist anymore - so that’s quite an interesting historical oddity there, isn’t it? But anyway, let’s see if I can put this thing back together now I’ve taken it apart and try to hook up some kind of power supply to it…
…and I’m back! As promised - and as you can see, I’ve also dimmed the studio lights for your convenience, so you can see this beautiful backlight - pretty much the only sign of life I’ve managed to get out of this laptop. Yes, I did come up with a bit of a ghetto power supply solution. I-
Okay! Uh, yeah, it also does that occasionally as well…
So I came up with a bit of a ghetto power supply solution: it’s a DC barrel jack with a couple of crocodile clips crimped onto the end, which are clipped onto that internal battery connector but unfortunately this only works about half of the time - and when I say “works”, what I basically mean is the power lights come on, the backlight comes on, it makes a bit of a clicking noise and… That’s it. No further signs of life, no hard drive activity and no sign that it is even attempting to boot - so, quite promising I think. But unfortunately it’s going to need a bit of further troubleshooting.
So I’m going to make this a two-parter - and if part 2 never materializes, you’ll know that I never managed to get it working - so I guess you’re going to have to subscribe to find out!
So if you enjoyed the video, please do give it a thumbs up, big thanks as always to my supporters on Patreon, Ko-Fi, and indeed my YouTube channel members as well - they get the videos a little bit early and also ad-free - and a big thank you to you for watching - and I’ll hopefully see you next time.
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