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 <[email protected]> 
> 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.

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