I stumbled across this thread while looking for information about two items that I recently acquired - a Digiac 5502 monochrome monitor exerciser and a Digiac 5503 dot matrix printer exerciser. They were given to me by a friend whose former workplace used them years ago. The 5502 appears complete, and I still have a monochrome monitor in storage that I can use to test it. The 5503 has had two cables dyked off which presumably went to two connectors, probably a DB-25 to a computer and a Centronics to a printer. The 5502 has a cable for a video card and a jack for a monitor, so I am presuming somewhat similar construction for the 5503. I have old printer cables that I can put on it - I should be able to figure out the wiring. I even have two dot matrix printers here, including spare ribbons and a box of tractor feed paper. I haven't used a monochrome monitor since my CP/M days, but some of my customers still have legacy equipment that uses dot matrix printers.
These excercisers are nicely built and very solid. I do not have manuals for either of them. Both have locks but both are in the unlocked position. I don't know when I will get to dig into them - aside from several items of work queued up in the shop I have a backlog of projects, and I need to repair a few items of test equipment first.
