Power supply connector pin crimping, and 8-inch FDD power connectors (another chapter in the Quay 900 saga)

Jay Jaeger cube1 at charter.net
Thu Aug 20 23:23:57 CDT 2015

On 8/20/2015 10:16 PM, Eric Smith wrote:

> It turns out that even though this bizarre variant of the 9406 uses
> the Shugart pinout for the data connector instead of the MPI pinout,
> and uses the same DC power connector as the Shugart, instead of the
> header used in normal MPI 9406 drives, the DC power connector pinout
> for the MPI does NOT match the Shugart DC pinout, as also used by the
> various half-height drives I want to try. I'm becoming less and less
> impressed with these MPI drives as I learn more about them.

One of the things I learned in working with the SA-800 series is that
they can accept either unregulated -12V or regulated -5V on pin 4,
depending upon how jumper L is set.  But the specs do talk about that,
and the specs on my Siemens FDD 100-8 match the Shugart power pinout
(the -5V regulator, though, is apparently option, and not necessarily
present on every FDD 100-8).  There is passing mention of an SA 800L in
the Shugart OEM manual that apparently does not require this negative


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