[Info-vax] Old junk breaks

[Steven Schweda]

> If needed, I cut off the old plug and splice it onto the new one.
> But nicer to find one with the right plug already.

   The problem here is that the DEChub Work Group Units (such as the
DECSserver 90M) have two connectors for power: a two-row x 16-pin
male odd-ball, and a 7-pin female Mini-DIN.  The DEChub backplane uses
the 32-pin odd-ball; the individual-unit supply (which I don't recall
ever seeing) uses the Mini-DIN.

      https://manx-docs.org/collections/mds-199909/cd2/network/dehubom1.pdf

   I'd expect that finding an adapter with either of these is unlikely,
at best.  What I use is a spliced-on cable with an 8-pin male Mini-DIN,
which seems to be close enough.  (The extra pin on the 8-pin male falls
neatly into the keyhole of the 7-pin female, contrary to the impression
given by the picture here:)

      https://en.wikipedia.org/wiki/Mini-DIN_connector

   According to that article, PS2 mice used 6-pin connectors, so it's
more likely that I got my 8-pin stuff by bisecting some kind of
serial-modem cables.  It's been a while, so I don't remember what I
chopped up to get the 8-pin male Mini-DIN.

> For more specialized ones, especially more than one voltage,
> I would probably try to fix it.

   Most of the Work Group Units use 5V only.  A DECrepeater 90T+
(-DETMR-N), or a DECserver 90TL (-DSRVE-M), or a DECserver 90M
(-DSRVH-M), for example, says "5.1Vdc 1.8A, 9W".  The DECrepeater 90TS
(-DETMI-M) is one of the few which also wants 12V (under some conditions
or other?).  It says (confusingly):
      1.2 A @ 5V
      0 A @ 12 V
      0.5 A @ 12 V W/AUI  6 W

   On the bright side, my power supply seems to be able to power a
couple of Work Group Units without generating any smoke.