@ Ninive The circle with the prefix is the year of manufacture of the frame. You find that on the Unis models, and, as Uwe says, there is nothing lika that on the Germany-made models, so it seems you actually have a Yugoslavian machine. I suppose it was not by a choice by Unis to mark the frames, but a precondition by Olympia in order to be able to tell the one machines from the others.

kpropaganda wrote:

@ Ninive The circle with the prefix is the year of manufacture of the frame. You find that on the Unis models, and, as Uwe says, there is nothing lika that on the Germany-made models, so it seems you actually have a Yugoslavian machine..

And I just finished insisting it was a German-made model!  Then again, I can't see the photos of the frame that you're referencing because it appears that ninive deleted them, and from memory I don't remember seeing the UNIS stampings in his photo of what he thought was a serial number.

kpropaganda wrote:

I suppose it was not by a choice by Unis to mark the frames, but a precondition by Olympia in order to be able to tell the one machines from the others.

Or, UNIS stamped its name on the frames because it wanted to differentiate itself from Olympia made models. 
Wouldn't it be great if we could just ask someone from Olympia about all of this? Surely there must be many people still around with knowledge of this? If I was in Germany and my German was better I would definitely be pursuing that angle...
 

ninive wrote:

What should these markings look like?

Maybe you could repost the photo that you removed that I think kpropaganda was using as reference?

ninive wrote:

On this post the author says that for a time they were produced simultaneously both in Yugoslavia and in West Germany.

If there were crossover machines then you probably have a Yugoslavian made Olympia that was assembled in Germany. There are rules concerning the use of the "Made in Germany" marking on your machine that I'm sure a corporation such as Olympia would have respected.