2 answers
Hello;
Realistic was Tandy France and RadioShack US, I know it will be tough.
Are you looking for the user or technical manual?
Hello,
See if this notice for model 31-198 8 can help you:
https://www.eserviceinfo.com/pdfview.php?fileid=67570
and/or
https://www.eserviceinfo.com/downloadsm/67570/Realistic_31-1988.html
It's very difficult to catch a black cat in a dark room.
Especially when it's not there...