Leonard Erickson wrote in a message to All:

 LE> Digging thru my junk box, I stumbled upon an old Inmac gizmo: 

 LE> SP-64
 LE> Serial-To-Parallel Converter
 LE> and 64K Buffer
 LE> Product No.
 LE> 8149-1

 LE> It's got a coax power jack, and no indication of what voltage
 LE> polarity it wants. 

That's probably easy enough to figure out,  looking at the inside.  Odds
are pretty good that there will be a regulator of some sort in there, 
anyway...

 LE> There's also a 8 position DIP switch inside (probably for setting 
 LE> serial parameters).

That could be somewhat more difficult.  

 LE> Before just tossing it, I figured I'd ask if anybody knew anything
 LE> about it. If I could get the info, I could actually use it with
 LE> some other equally ancient gear (like actual *terminals*).

Like maybe hooking up a parallel printer to the "terminal port"
on one?  :-)

I remember terminals,  even have some in storage,  along with the rest of my junk.

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