3B1 Hard Disk Woes (Plea for HELP!)

[Chris Lewis]

Talk about timely!

I'm posting instead of mailing because of the co-incidence (and we *know*
what's wrong with ours...  Graphically.)

In article <8569 at cbnews.ATT.COM> kww at cbnews.ATT.COM (Kevin W. Wall) writes:

>I am having trouble with my hard disk on my 3B1 (a 67Mb Miniscribe).

So am I.

> For example, if I run the diagnostic
>to park the heads on the hard disk, I will get the following output:
>
>		WINCHESTER DISK TEST
>
>		Hard disk restore failed
>			**ERROR**
>		Test:		Hard disk test (drive 0)
>		Subtest:	Park Disk Heads
>		Error:		WINCHESTER: Can't Recal; Response = 4
>			Enter y[Y] to Abort, Return to continue

That's what we get too.

>	1) What exactly does "Can't Recal; Response = 4" mean?  In particular,
>	   what does this most likely indicate?  (E.g., a problem with the disk
>	   controller, with the hard disk media, etc.)

That the drive cannot find the first track on the disk.  I'm not sure how
good the diagnostics are, but I do know that you really cannot do anything
with a disk if you don't recalibrate first.  Unless your diagnostics are
capable of actually testing the controller (which I doubt in this case),
it's hard to tell whether it's the controller or disk.  My system originally
didn't boot HD or floppy, but we eventually got the floppy running, ruling
out the rest of the logic board except possibly the controller itself.  Could
have been a bad diagnostic floppy (was an off-the-net copy of s4diag that
I had booted successfully once before) that prevented the floppy boot at
home.

>	2) Can I safely assume that the problem is in the hard disk UNIT
>	   (all the pieces inside the smaller cage containing the disk itself),
>	   as opposed to being some kind of problem on the mother board?

Not necessarily.

>	   [The reason that I want to no this is that I have a 72Mb Miniscribe
>	   (Model # 6085) that I could (would like to) install to replace the
>	   (bad?) drive, but don't want to do this it there is a problem some-
>	   where on the mother board which will cause this one to fail too.]

*Very* unlikely - on ST506 drives you can do almost anything to the connections
without harm (eg: getting either cable backwards...)  Unless something's
wrong with the powersupply - a VOM would come in handy.

>	3) Is there any way, short of opening the sealed drive itself, to
>	   tell if the problem is a head crash (vs. say, the failure of the
>	   hard disk controller)?

No.  But there can be additional evidence.  Eg: loud scraping noises.
Which is what I been getting louder and louder over the previous week or
two.  Originally thought it was the fan dying, but once I had the cover
off, it became obvious where it was really coming from.

Another thing that might help is opening the 3b1, disconnecting the ribbon
cable from the power supply to the logic board, and powering the thing
up.  If the drive spins up reasonably quietly with no activity on the
HD drive LED (seen through the perforations on the HD cage), you probably
still have a good drive.  Mine made noises and the LED gave me a repeating

flash ... flash-flash-flash ... flash-flash-flash ... flash-flash-flash

code.  Which might mean something if you have the right manuals.

If there is a true head crash, chances are that the drive isn't worth
repairing....  Generally speaking, repair houses charge a fixed rate
(on the order of $500-$1000) to repair a drive.  Even then, you generally
don't get data recovery (especially if some of the oxide is missing...)
And you can usually buy a new drive for less than the repair cost.

If the drive is truly zorched, I don't think that a repair centre
would care whether you had peeked inside.  Once you find one, you could
always ask.

In our case, our resident expert on 3b1 noises took the chance and opened
the drive this morning.  He has managed to take one apart, fix it,
and have it work after he's closed it up, but it should really be done 
in a "clean room".  

Oh my!

Heads 3 and 5 fell off, and there's this neat 1/2" wide stripe of melted 
aluminum where the head supports touched down on two of the surfaces.  
Lost a few square inches of oxide.  Starting at cylinder 0.  There go
my comp.sources.unix and comp.sources.misc archives - they're just
reddish dust on the workbench now.

Sigh.  I must be sick - I'm actually giggling about it...

I understand Jim Joyce (of UNIX bookstore fame) makes a living recovering
data from mangled drives, but he charges quite a bit (quite a bit for
a hobbyist, not that much for a company who's got lots of money riding
on their disk contents).

None of the people we go to for repairs would be of use to you "down there".

Now I just have to see if I can get another drive...
-- 
Chris Lewis, R.H. Lathwell & Associates: Elegant Communications Inc.
UUCP: {uunet!mnetor, utcsri!utzoo}!lsuc!eci386!clewis
Phone: (416)-595-5425