Hi guys it’s a serious post ...

I’ve opened my newly acquired ep128 to do some maintenance, fixed a keyboard contact on the membrane, installing a 2.4 exos eprom and some contact cleaning on the edge for my newly build disk drive interface (thanks to Pear for all info and schematics).
Now at some point this thing on the foto dropped from somewhere, is this some sort of factory patch or user work, just to put it back for originality.
Thank you.

Here is the serial number, one more question.
I have the 03-07 cartridge with basic and German keyboard 128 EPROMs, i modded it as from your schematic to use 256 eprom and transfer the exdos eprom from the dd interface in place of basic to use the extra ram option on it and it works perfectly, I now have 512k ram. Will this mode allow also to use 512 EPROMs?
Thank you

Ps. Never mind just saw pin 1 a15 is on vcc so clearly no, ha ha