I just picked
up an HP 97 at a church rummage sale.  [...]
 and the external power connector is marked 5V. 
 It should be marked 8 volts.  The
charger for them has an 8 VAC 3VA
 output. 
 
Maybe it's not a charger, then, but just a calculator power supply.
It's fairly clearly maked "5 VOLTS 2 WATTS".  Doesn't say whether AC or
DC, even, which I found surprising.
   Even the
printer works (though the ribbon appears a little
 enfeebled). 
 There is no printer ribbon.  it uses thermal paper. 
 
Certainly not normal thermal paper.  Most thermal paper will show a
mark if I draw my fingernail across it when it's on a hard surface; I
tried that with this paper and it does nothing.  I haven't tried
heating the paper, which of course is really the acid test.
Also, the print started out light and got better, which is indicative
to me of a ribbon that had a dried-out spot and has now moved to a
better area.
Perhaps I have a 97 with a rare ribbon print mechanism? :)  I'll
probably open it up, if only to convince myself what the external power
_really_ should be (I've been connecting to the battery connector, not
the external power connector) and, if DC, what polarity.  I can look at
the print mechanism when I do.  I can also try heating the paper to see
what happens.
   The thing cost
me all of five bucks. :) 
 You can make a nice profit on E-bay :-) 
 
Nope, I never use ebay. :)
  BTW you do know that the slot on the LH side is for a
mag card reader
 don't you? 
It took a while, but yes, I realized that eventually.  It came with no
cards, though - is it possible to make them with something like a piece
of magnetic tape and some thin stiff plastic or some such, or must they
be The Real Thing?
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