Very Computer

by **Alex Nghi** » Fri, 04 May 1990 00:30:19

We have a CDC Wren III that just crashed. Our tests indicate boot
sector 0 is bad. However, upon closer observation we note that
the clicks that normally occur when the auto head park mechanism
disengages upon power-up is not there any more, leading us to
speculate that maybe the head is stuck in the park position.
Is this a common occurence with CDC Wren drives? Is there a
simple fix?

__________________________________________________________________________
This article is posted for discussion only. Any misrepresentation,
if any, is purely unintentional. Any opinion expressed or implicit in
these remarks are solely my own.

!cs.utexas.edu!ut-emx!nghiem

!cs.utexas.edu!ut-emx!ccwf!nghiem

by **Dave Emmers** » Mon, 07 May 1990 12:49:18

> We have a CDC Wren III that just crashed. Our tests indicate boot
> sector 0 is bad. However, upon closer observation we note that
> the clicks that normally occur when the auto head park mechanism
> disengages upon power-up is not there any more, leading us to
> speculate that maybe the head is stuck in the park position.
> Is this a common occurence with CDC Wren drives? Is there a
> simple fix?

Probably not actually 'stuck', more likely the stepper motor
amplifier blown. If you haven't done anything silly there's
a high probability of repair without loss of data.

We had a couple of problems with early models, but none have
so far done anything like that.

Dave E.

by **Alex Pournel** » Wed, 16 May 1990 17:40:33

>> We have a CDC Wren III that just crashed. Our tests indicate boot
>> sector 0 is bad. However, upon closer observation we note that
>> the clicks that normally occur when the auto head park mechanism
>> disengages upon power-up is not there any more, leading us to
>> speculate that maybe the head is stuck in the park position.
>> Is this a common occurence with CDC Wren drives? Is there a
>> simple fix?

>Probably not actually 'stuck', more likely the stepper motor
>amplifier blown. If you haven't done anything silly there's
>a high probability of repair without loss of data.
>We had a couple of problems with early models, but none have
>so far done anything like that.

Yah, that's a good possibility. We see a great lot of drives like that,
which are quite repairable/retrieveable. What kind of interface does the
drive have (SCSI/ESDI/MFM)? An MFM you can step around more easily and
look at the data.

The biggest problem with the CDC/Imprimis/Now-seagate drives, now, is
GETTING PARTS. The takeover has really dinked up the supply, grumph.
Other than that, the drives are true gems.

If you are in dire straits, let me know. I'll try to assist.

Alex
--
Alex Pournelle, Workman & Associates
Data recovery specialists for PCs, Macs, others
...elroy!grian!alex; voice: (818) 791-7979
fax: (818) 794-2297 bbs: 791-1013; 8N1 24/12/3

Very Computer

CDC Wren III hard drive parking mechanism

CDC Wren III hard drive parking mechanism

CDC Wren III hard drive parking mechanism

CDC Wren III hard drive parking mechanism