Noel said > The "Spare Module Handbook" lists: > > ... > > MX11-B > > I apparently can't read. Should be "MX15-B": > > https://gunkies.org/wiki/MX15-B_Memory_Multiplexer
Would that be part of this system at a Japanese computer museum? There is an 11/15 and the 11/05 has 'Unichannel15' on it: https://www.kcg.ac.jp/museum/en/computer/mini_computers/dec.html