Heatkit 5 1/4 floppies

From: Joe <rigdonj_at_intellistar.net>
Date: Thu Apr 8 15:15:59 1999

Dick,

  I don't know if they're supposed to run all the time or not, but both
drives do it so I don't think it's a problem in the drives. A lot of the
older drives had jumpers to cause them to run continously. I guess it
saved the time needed to spin the drive up to speed. Several people have
said that they have systems with 5 1/4" drives that spin all the time so it
may be normal. Allison says that her 8" drives have run thousands of hours
without problems so I hope it's not a problem.

   Joe

At 11:50 AM 4/8/99 -0600, you wrote:
>8" drives typically spun all the time, as their motors were AC types. If
>your 5-1/4" drive spins all the time, something's wrong. They had a
>nMOTOR_ON signal which you can monitor to determine whether it's a defective
>drive or a bunged-up driver. One important reason for the popularity of the
>smaller drives over the AC-powered 8" types was noise. If the drive is
>running all the time, clearly there's something wrong. It could be in the
>jumpering of the drive or in the controller firmware. It could even be a
>jumper option on the controller. You'll ruin lots of floppies in a drive
>which doesn't stop and which doesn't unload its heads. It's easy to monitor
>the control signals. If the controller tells the disk drive to keep
>spinning, you need to "fix" the BIOS code.
>
>Dick
>-----Original Message-----
>From: Joe <rigdonj_at_intellistar.net>
>To: Discussion re-collecting of classic computers
><classiccmp_at_u.washington.edu>
>Date: Thursday, April 08, 1999 9:13 AM
>Subject: Re: Heatkit 5 1/4 floppies
>
>
>>At 09:43 PM 4/7/99 -0700, you wrote:
>>
>>People today don't realize that the old
>>>systems used a floppy like present systems use a hard drive, almost all
>the
>>>time, which is a heck of a lot of wear for a contact media.
>>
>> I used to work for Burroughs and they had a computer that used 8"
>>floppys that spun continously. Burroughs said to replace the disks every
>>100 hours. I have no idea how long they would actually run before failing.
>> Does anyone know? I have a CPM machine that spins it's 5 1/4" disk
>>continously but I haven't run it enough for a disk to fail.
>>
>> Joe
>>>
>>>
>>
>
>
Received on Thu Apr 08 1999 - 15:15:59 BST