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.
