Pleas ID this IBM system....

Lawrence Wilkinson ljw-cctech at
Mon May 20 15:30:18 CDT 2019

On 20/05/2019 18:42, Chuck Guzis via cctalk wrote:
> The model 20 installations that I played with were mostly to supplant
> unit-record gear, which typically did not use a raised floor
> configuration.  Mostly the CPU, card mulcher, printer and perhaps a 2311.
> The installation auctioned off is one of the larger Model 20 setups that
> I've seen.
> --Chuck

As Adam isn't on the list, and I am one of those in that photograph...

There was one 360/20 (pink) that was cabled up with 2 x 2311 disk, 2 x 
2415 tape, 2560 MFCM and (I think) the 1403 printer. That system appears 
to have been in use at that site. The second 360/20 (blue) was not 
cabled to anything, and the 370/125 (yellow) likewise. So I expect 
neither of those was used at all.

It can't have been a serious commercial installation, but maybe it was a 
keen hobbyist who acquired the systems and decided to keep them running, 
or perhaps used as a training tool. It apparently hasn't been used for 
30+ years.

The "raised floor" was in a sorry state, the heavy units had sunk into 
the soft wood panels. I guess the framing might have been useful.

It was good that all the punch cards required seem to be there and in 
good condition: the Control Program (microcode) cards for the /20, RPG, 
BAL etc. These need to be read - I know there are services that will 
process scans, but is there anywhere (UK/Europe) that can take the 
physical cards and give us back files?

The guys did a wonderful job, especially on that last day when they 
managed to move most of the units and clear everything out. As 
mentioned, the /20 CPUs and 2415 master unit were 500-600kg each and 
about the limit of the tail-lift.

If anything I've written here is contradicted by anything in the blog, 
believe the blog!

Lawrence Wilkinson                                 lawrence at
The IBM 360/30 page             

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