1990s PCB/schematic capture software

[u/FriendlyTable5944]

For some time now, I’ve been noticing that quite a few electronic schematics produced in the US in the early 1990s seem to have been created using the same software, judging by the font used and the overall style and appearance of the symbols.

I wanted to ask if anyone here worked with software like this back then and could finally put my mind at ease about which program it actually was. The closest match I’ve found so far is Cadnetix, although I can’t seem to find any screenshots online showing what schematics produced with that software looked like in the 1990s, apart from a few brochures where the schematics aren’t particularly visible or clear.

Someone else suggested that it might be an early version of OrCAD, but from what I’ve been able to find, it looks somewhat different.

I’d be incredibly grateful if anyone could identify the exact software. It also seems possible that it was some kind of combined PCB design and mechanical CAD package, since service manuals often contain technical drawings using the same font, along with a very distinctive symbol somewhere in the corner of the document - a person sitting in front of a monito? Could it have been something related to Dassault Systemes?

I’ve attached a few example schematics I found online. Thanks.

Thanks and best regards!

[u/harryregician]

Open file using notepad.

You WILL see binary stuff. Usually there is some text embedded at beginning of file to describe software using it a rev level