[comp.os.cpm] Kaypro 10 harddisk errors

bridger%rcc@RAND.ORG (Bridger Mitchell) (06/23/89)

Charles West noted the importance of adequate cooling.  Heat buildup
has caused erratic performance in several Kaypro models.  In addition
to cleaning the fan filter, a good check is to remove the metal cover
and run the machine in the open, especially when the ambient room
temperature is high.

Controller chips can get too *cold* also!  When Plu*Perfect Systems
was in Idyllwild we had a Kaypro 10 in a minimally-insulated basement
office.  When powered-op on cold (20 - 30 degree F) mornings it would
often report as many as *100* bad tracks.  As it warmed up, fewer were
reported, and in an hour all was again well.  After that, we usually
left the machine running overnight!

-- bridger mitchell

h3x2@tank.uchicago.edu (andrew abrams shapiro) (06/24/89)

In article <8906231622.AA01389@newton> bridger%rcc@RAND.ORG (Bridger Mitchell) writes:

>Controller chips can get too *cold* also!  When Plu*Perfect Systems
>was in Idyllwild we had a Kaypro 10 in a minimally-insulated basement
>office.  When powered-op on cold (20 - 30 degree F) mornings it would
>often report as many as *100* bad tracks.  As it warmed up, fewer were
>reported, and in an hour all was again well.  After that, we usually
>left the machine running overnight!


It probably wasn't chips, but the drive itself!  In my PC experience, many
machines equipped with Seagate 20 or 30 Mbyte drives have serious problems
with physics.  That is, parts of the drives expand/contract with
temperature changes, which, uh, moves the tracks around a little.  I've
seen a machine that had its HD formatted in an air-conditioned room start
to die after it warmed up a little.  I suspect in the above case that the
disk wasn't formatted under cold conditions, and contraction caused problems
until the disk warmed up from the PS/drive motors/etc.

So before you check your chips, stabilize the machine at a reasonable room
temperature and see if you STILL have trouble...  If you don't, I'd be willing
to bet the trouble is mechanical, not electronic!

--Andy 

josef@ugun13.UUCP (06/27/89)

In his response, Andy ??? (h3x2@tank.UUCP) writes:

 > It probably wasn't chips, but the drive itself!  In my PC experience, many
 > machines equipped with Seagate 20 or 30 Mbyte drives have serious problems
			  ^^^^^^^^^^^^^^^^^^^^^^
 > with physics.  That is, parts of the drives expand/contract with

This is not only true for the drives of any specific hardware manufacturer.
When I started working with our company some 8 years ago, we used removable
disks (who didn't at that time?) and the first hint everybody gave you was
to insert a disk pack (remember that word: "disk pack"?), then switch
on the drive and have a cup of coffee in order to have the pack at the
proper temperature.

		Josef Moellers

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