Well as described in my last post one fly wheel of the capstan was broken. It is impossible to get one and quite an effort to create new one. However, I rebuilt the wheel just to be able to check other functions. Of course my wheel is not stable and would lead to horrible wow and flutter parameters. It is a critical part that we are talking about.
Well I noticed later the lid has broken hinges. The main gear looked good at the beginning but right after some rotations it lost the teeth. Of course I can replace the gear.
But without a proper fly wheel I will not be able to get it working. Since I already have three working units I think I will use this one as a donor for the other devices. Unit #2 for instance would need a new LCD display.
I am still going to repair all PCBs to have some working spare parts.
However, unit #4 was still a bargain for just 20€. Some important and cheap spare parts.