Jumpering for NEC FD-1165H 8-inch floppy drive

From: Steven N. Hirsch <shirsch_at_adelphia.net>
Date: Sat Jan 3 08:59:34 2004

On Fri, 2 Jan 2004, Nico de Jong wrote:

> From: "Steven N. Hirsch" <shirsch_at_adelphia.net>
> > Title says it. Can anyone point me to online data for this elderly
> > device?
>
> No, but I have the straps for teh FD1165-FQ, as used in my media conversion
> systems.
> I am looking at a "naked" drive right now, with the front towards the
> right. I can see a number of straps, e.g. the one called US. This one has a
> jumper on the righthand part, and is therefore designated below as US 1
> Are you sure the voltages are on the correct pins ?

The "H" model is older and uses a square 6-pin Molex connector (same as
all my other 8-inch drives), so I'm sure the voltages are correct.

There are some notable differences between the FD1165H and "-FQ" models.
After reading the service manual on Al Kossow's site (thanks to all who
pointed me there), it seems that the motor is supposed to turn on disk
insertion and is not gated by select or head-load signals - at least on
the FQ variant.

So, why on earth would (2) functional drives just decide not to spin? In
the interim, I installed a (mis-matched) pair of one-each Qume and Tandon
1/2-ht. drives in the same box. These work fine, indicating that I'm not
dealing with a power-supply or data cabling problem.

A little poking with a voltmeter shows that the motors in the NEC units
are not receiving power. Once again, the head stepper and head-load are
working properly on these units. Another symptom: The NEC units have (2)
status LEDs on the front bezel; ready and active. The ready LED is
supposed to illuminate when power is applied and a diskette is present.
It does not.

Anyone have a suggestion for troubleshooting?

Steve
Received on Sat Jan 03 2004 - 08:59:34 GMT