I apologize in advance, if this isn't the right place to ask this. I want to find out, what kind of electronic device this is. The tape recorder is just on top of it, but I am talking about the device beneath it. It is integrated into a metal suitcase, it is manufactured by Siemens, and the keyboard doesn't have letters on it, but instead has weird combinations of letters on it, like OMN, OA etc.
May be an old plc programmer. The text of the three positions of the key may help to discover. Also the identification of the sub-D connectors. Could you tell us?
It seems to be a PLC programmer from the age of no-pc-at-home. The PLCs had very little RAM (a few Kbs) and only proprietary interfaces. I have never seen a programmer that big, just handheld devices. In fact, nowadays Siemens programmers are pc-based devices but still called suitcases.