Earlier quoted context omitted.
> "I do remember that each consumer device was sold there with its schematics, assembly/disassembly and installation instructions. And that was the law." That's interesting. I wonder if there's a archive of those schematics/documents for Soviet consumer devices somewhere.
A lot of western instrumentation and test equipment used to come with full circuit diagrams and assembly info. The understanding was that your HP spectrum analyser or Tektronix scope cost so much money that if it broke then you would have it repaired, and to do the repair you need the circuit diagram.
As an example, can see hardware schematics in the Apple II Reference Manual found here:
http://www.applelogic.org/UserManuals.html
I'm mostly interested in the Soviet material as I'm assuming that because it was a legal requirement the types of documented designs will be more broad, but if you know of an archive of old Western schematics also, I would be interested in taking a look.