[jan-jaap]

Maybe a good addition (but I think it's from Power series era)
https://www.kleinanzeigen.de/s-anzeige/s...1-228-7862

I have two meters of those brown binders already

Do you have any background on this particular machine,  original usage etc ?

Not much. The person I got it from, who was the original user, was a software development consultant. I know he also discovered the flight sim (dog). My guess would be something related to the military. A university or business would not write off the machine in 3 years and (in 1990!) care enough about security that they would degauss the whole thing.