Help Needed: Kaypro 10 HDD Problems

From: Don Maslin <>
Date: Mon May 11 23:45:23 1998

On Mon, 11 May 1998, Grant Zozman wrote:

> I recently added a Kaypro 10 to my collection, but it seems to have met with some rough handling
> in shipping. If anyone can shed some light on the problem described below, I would REALLY
> appreciate it (any Kaypro experts out there?)
> When I first fired it up, it booted from the hard drive right away. However, as soon as I tried
> to access the HD further, all I got were "Bad Sector" errors. Since then, the computer will no
> longer boot from the HD, and I can't access any information on it ( not a good sign :-( ).
> Using CP/M, I have tried to re-format the drive with no luck; all I get
> are "Verify Errors" as it
> tries to format. So much for the theory that the heads may have gotten
> knocked slightly out of
> alignment!

Do you have the PUTSYS and PUTOVL programs on floppy? These are the hard
disk equivalent of SYSGEN, and are needed after format to make the drive
> Re-seating all connectors on the drive and controller didn't help either.
> I have pulled the drive from the computer and hooked it up outside the case. It does spin up to
> normal operating speed, and I can see the head stepper motor responding in a normal fashion when I
> attempt to access the drive (formatting, parking the heads, pulling a directory, etc.). None of
> the linkage to the heads seems damaged or broken; in fact the entire computer is in excellent
> shape and has not been abused. The hard drive activity light (which is controlled from the drive
> itself) also seems to respond normally.
> No untoward noises seem to come from the unit when it is operating, although I do hear some
> metallic "singing" during the last second or so just prior to the drive coming to a complete stop
> on power down. I'm not sure if this is just the brake mechanism, or if it is the heads against
> the platters (I do park the drive prior to powering off, though).
> Based on the above, I am assuming (wrongly so?) that the controller is probably working OK. It is
> a Western Digital WD1002-HDO. My hunch is that either the drive electronics or the drive itself
> have failed.
> Are there any other tests I should by trying? Am I correct to assume that it is the drive which
> has failed?
> The drive is a Tandon TM502 (10MB, MFM, 5 1/4" platters). If the drive cannot be salvaged, I
> would appreciate hearing from anyone who has a replacement drive, or knows of a source for same.
> I would like to keep the same make and model drive if possible, but an equivalent model would be
> fine too (as I'm sure Non Linear Systems used more than one make of drive in the Kaypro's).

That is most likely a replacement drive, as the originals were one of
Microscience, Seagate, or Shugart. You can replace it with any MFM hard
drive that has at least 4 heads and 306 cylinders. An ST-225 or clone
comes to mind. Of course, with the Kaypro ROM you will only be able to
access 4 heads and 306 cylinders, but it opens up the available list of
drives rather wider. With the Advent TurboRom, available from TCJ, you
can make use of a wide variety of drives on up to 40mb, as I recall.

                                                 - don

> Any help is much appreciated!
> Grant Zozman
    Don Maslin - Keeper of the Dina-SIG CP/M System Disk Archives
         Chairman, Dina-SIG of the San Diego Computer Society
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Received on Mon May 11 1998 - 23:45:23 BST

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