Thanks to everyone who replied! So far, the verdict is the following: 1) the modular systems are NGEN from Convergent Technologies; they have 80186 cpus, which make them B25 modules (thanks, Paxton) or CM001/8; they do operate from 36V externally supplied by one or more brick-style power supplies with RJ-style connectors; no hard disks were found with these, although, considering the manufacturing time frame, it is conceivable that they were entirely floppy-based; these units had dual floppy disk drives attached. I hauled a box with lots of docs and diskettes, but I have not had the time to go through it; the stuff might not be related to the Convergent systems. So, I need to (a) find a way to provide these systems with 36VDC, and (b) look for any related floppies; it may be that these machines can't be used without a password. 2) The Datapoing 1550 seems to be a diskless computer; there is a connector in the back that might have been used to connect a floppy disk drive or something else. I have spotted a couple of burned caps in the power supply (the computer smelled, so it was clear from the beginning that I could not take the chance of turning it on unchecked). There is a card cage in it, but I haven't taken anything but the cover off. carlos. -- Carlos E. Murillo-Sanchez email: carlos_murillo(a)ieee.org Universidad Autonoma de Manizales, Manizales, Colombia