[comp.sys.ibm.pc.misc] Help Needed With Miniscribe Hard Drive

jmh@coyote.uucp (John Hughes) (12/20/90)

Would someone happen to have technical info and/or experience with the
Miniscribe brand hard drives? I have a 42Mb drive (a model 3650, I
think... I didn't pay attention to the model number except to look up
the cylinders and heads data), and it's acting up in some odd ways.

First off, the drive appears to be very sensitive to supply voltage
fluctuations. It is mounted in a cabinet with several other drives,
and I originally had it sharing a DC power line with old 15Mb Tandon.
Every time the Tandon was selected, the front panel light on the
Miniscribe would flicker very weakly, and both the system and the
drive reported errors. On the Miniscribe the status light goes from
green to red when it has an error. After adding some ground lines
and rearranging the DC bus, 90% of the errors vanished, but... I
still get random rad/write errors every so often. These are not
at the same place on the drive (they can happen anywhere).

Secondly, the drive also appears to have troubles with the integrity
of the control and data signals. Neither of the other two drives
in the cabinet have any problems, and they are all being controlled
from the same Western-Digital controller card. The Miniscribe is
the first drive in the controller chain. The Tandon is last, and it
does have the end-chain termination resister pack installed. The
errors show up randomly, but there does seems to be a correlation
when the heads are moved over an extended distance (eg. as in when
the swap space is accessed). The correlation is very weak, however.

It's my hunch that these two problems are related. Is it possible
that the Miniscribe needs its own seperate supply? Or do I just have
a bad drive that needs to find a home in the dumpster?

Thanks.


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