Repairing original AT hard disk

[G Manuel (GMC)]

> On 5/29/07, Julian Wolfe <fireflyst at earthlink.net> wrote:
> > > One CLOK or multiple CLOKs?
> >
> > Just one.
>
> I have heard a single loud "tock" from working drives as they release
> the head-lock solenoid, but perhaps your head assembly is glued to a
> rubber stopper like in some failure modes of, IIRC, Micropolis 1335s,
> AKA DEC RD53s.  The solenoid would still trip, but the heads wouldn't
> load.
>
> > This is an IBM brand drive...
>
> Ah.  That model is outside my experience with PC-ATs.
>
> > and after doing some reading, I found out
> > IBM-brand drives of this era DO NOT park the heads in a landing
> zone, they
> > actually retract them.  (Perhaps like the Priam disk you refer to)
>
> I found some tantalizing info at the HTMLization of
> www.course.ws/techtalk/downloads/PDF/hardware.pdf in google's cache,
> but the HTML file stops in the middle of the entry for the AT, the
> original site is gone, and archive.org didn't have the PDF file
> cached.  If someone happens to have that file cached on their own,
> there's lots of meaty technical details on BIOS revisions and more.
>
> -ethan
>

Another possibility could be that the hard drive needs to be Low-Level
formatted. I have seen this behavior before and IIRC most times using DEBUG
to low-level format the drive will clear it right up. It is worth a try.
HTH.

Good Luck,
Greg