vintage computers in active use

Eric Smith spacewar at
Thu May 26 22:31:23 CDT 2016

On Thu, May 26, 2016 at 7:08 PM, Jon Elson <elson at> wrote:
> On 05/26/2016 06:18 PM, Mike Ross wrote:
>> It was a few years ago now and it's third hand - but I was told that the
>> US Navy still maintained a shop dedicated exclusively to repairing IBM SLT
>> modules... can't vouch for the veracity of that; perhaps someone else can.
> Hmm, I've thought about this a bit.  I think one could make up replacement
> SLT modules with little PC boards and SOT23 transistors and 0805 or 0603 SMT
> resistors.  SLT modules had very little on them, something like 2
> transistors and 4 diodes and some resistors.
> I was thinking about this in relation to keeping a mid-size 360 running for
> a few hours a month at a museum, like the 1401 at CHM. But, it would sure
> work for actual full-time operation, too.

Another CHM volunteer (from the PDP-1 Restoration Project) and I
pushed for an IBM 360/30 Restoration Project, and the ability to build
replacements for failed SLT modules was part of our plan.  I donated a
2540 Reader Punch to CHM with the hope that it would be used on the
360/30, but unfortunately I missed out on getting the 2821 Control
Unit that went with it.

Unfortunately, for various reasons it is unlikely that the CHM 360/30
will be restored.

More information about the cctalk mailing list