Hi Joerg,
Well I'm sorry to hear that. As an analogue guy, I don't much care for
PROMS and stuff. I can fix up anything analogue in good time, given a
schematic and a decent range of test equipment, but am off my territory
with digital stuff. But I'm still not sure what the problem is here.
Are you saying spares for the digital parts are hard to obtain or
rather that the encoding on those chips may be hard to reprogram?