Spent some time fixing this keyboard. Itś a Unicomp Model M (yes, an IBM model M clone) but with the Dvorak layout! Bought it in 2015 and at some point it stopped working: on some rows the key presses didn´t register. Requested a repair quote but excluding shipping it was already €150 so I was like nah. Had it stored somewhere since then. Today I wondered if I could fix it myself. Took it apart and it seems like the inside chip needs to be properly pressed down. So I made a wad of a paper cloth, put it on the circuit board, closed it up and voila, it works like a charm again!