So today, I got a computer!
It took all day and a rental truck, because it turns out it's really heavy. It's a minicomputer, a National Semiconductor Datachecker 1730.

I don't have a lot of pictures yet because I've been too focused on successfully getting this machine. I'll take more as I can.

So I got a message the other day about this one, it was in a supermarket that was shutting down. Apparently it had been installed early in the life of the store, around 1986.

At sometime in the 90s, it was decommissioned, but not removed: it was heavy!

and right now the building is empty and I believe able to be torn down, so it was finally time to get it out or let it get scrapped.
So when I was contacted about it I grabbed a rental truck and headed up there

It mainly took half the day to get because it turns out not only does it weigh something like 600 pounds, it was at the top of a set of very narrow stairs. No wonder they never removed it...

But by mostly disassembling it (mainly removing power supplies and hard drives) we were able to get out out and into a truck.

So, the system itself: There's not a lot of information about it online, yet!
National developed the Datachecker system in the late 70s:
It was a system for managing supermarkets. This would have many POS systems wired into it, and at the time those would be dumb terminals.

That's what this video is about: https://twitter.com/Foone/status/1344692018887344134

This is a later version of that system, apparently a more modernized mid-80s version.

So National Semiconductor bought Itel Corporation in 1979, and their IBM-compatible-mainframe leasing business (using mainframes made by Hitachi)
So it's possible this system is a rebadged IBM-compatible minicomputer by Hitachi, previously designed/sold by Itel.

National Semiconductor didn't have a good second half of the 80s, losing lots of money, and the Datachecker line was sold off to the British company International Computers Limited for half a billion dollars.

ICL merged with Fujitsu in 2002. So possibly I can yell at Fujitsu and get some documentation on this thing? I kinda doubt it.

But if anyone knows anything about the Datachecker minicomputer line, please let me know!

fun fact: National Semiconductor also used the name for... calculators.

That model apparently dates back to 1979.

Anyway: I'm gonna take more pictures once I get it into storage and partially reassembled (it's currently still in a moving truck), and I'll do more research.

Here's the serial panel for the unit. Apparently the model is specifically the Datachecker 1700, the 20 probably refers to something like speed/memory size.
And it has a manufacturing date of Dec 1986.

The couple things @gewt and I noticed while taking it apart:
It has two hard drives (HUGE MOTHERFUCKERS), a single 8" floppy drive, and we got some disks for it: all of them seem to have scribbled out labels, so they may be blank.

the most interesting thing is that it looks like it's not actually A computer: it's TWO COMPUTERS.

Nearly every part of it seems to be duplicated.
Like if you look here, you can see there's two power supplies running up to two sets of backplanes

If you look at the picture of the cards pre-removal, you can see that they seem to be roughly duplicated.

And if you go back to that front panel, you can see that it has a clear 1 and 2 sections.

So I think this system was designed as two identical copies of the same computer, with automatic (or semi-automatic?) failover between them.

Which makes sense if you think about how this would have been powering a whole set of supermarket checkout registers.
If this goes down, you lose all your lines. You start losing money by the minute.

ANYWAY I brought in all the cards so I could look over them and take pictures and I will do that soon.
right now I'm trying to rest off having to move a quarter ton of computers

there also apparently was a novelty Datachecker... yoyo