Hey Paul,
Thanks for your comments!
Our 38 is actually a fairly late machine - it was manufacrured in late 1987, less than a
year before the AS/400 was announced, and was in use well into 1990. It has one internal
62PC drive and an external 9332-400 drive. I believe (and I hope) that it was configured
the way you mentioned, which was best practice for the time - 62PC just used for
microcode, and the external DASD for the OS.
We had the 38 for most of a year before the external DASD was located, so there wasn't
much hope for recovery until recently.
We do have a bad spindle motor on the 62PC, I have voltage going into it but not skinny
coming out of it, so that replacement will happen soon and we should be able to IPL.
I can read diskettes from the 72MD so thats spindle motor is good. I've replaced (and
re-bearinged) a lot of those back in the day.
Joe
On Jun 23, 2026, at 9:13 AM, Paul Berger via cctalk
<cctalk(a)classiccmp.org> wrote:
You may want to look around inside for seized fans. S/38s typically ran 7/24 and when
turned off one or more fans would fail to start when the system was restarted. Another
thing to check would be the motor on the on the 72MD diskette drive. My experience when
servicing S/38 was whenever I wanted to run diagnostics from diskettes I would first have
to free up or replace the motor. Like a usual 8" diskette drive the spindle motor is
an AC motor that is powered whenever the system is turned on. Most customers rarely used
the diskette drive so did not notice it was seized.
My recollection is the logic in the systems is solid, perhaps the weakest part is the
62PC (Piccolo) disk unit inside that stored the systems microcode. Most customers
isolated it from the storage pool so they would not have to reload the entire system when
it packed it in.
What do you have for storage on the system? Originally the systems supported multiple
62PCs inside or 3370s (the controller is not the same as the one used on 370s) Later
there was an option offered to support attachment of 9332 or 9335 disks. The 9332 200 and
400 are probably the most robust of the lot.
Paul.
On 2026-06-22 20:53, Joe George via cctalk wrote:
> We've been working on restoring and powering up a fairly rare bird of IBM
Midrange machine, the IBM System/38.
>
> We had some good success this past weekend that I'd like to share.
>
>
https://crusty.computer/?p=89
> June Work Recap: Edith – The Crusty Computer Club
> crusty.computer
>
>
> tl;dr: she powered up and no smoke came out and no sparks came out! There are several
repairs needed but they are known and fixable.