youtube video of a runnning XDS Sigma mainframe with lots of nice peripherals

Rich Alderson RichA at
Mon Nov 2 16:15:53 CST 2015

From: Lee Courtney
Sent: Saturday, October 31, 2015 10:37 AM

> I posted the video you linked to. The machines on the video belonged to
> George Plue, who ran a medical billing service bureau in Flagstaff AZ. They
> are now located at the Living Computer Museum (LCM) in Seattle.

> George originally ran the Computer Center at Anderson University in Berrien
> Springs MI, and the center ran several generations of SDS the XDS Sigma
> mainframes over the years. When Xerox decided to get out of the mainframe
> computing business in August 1975 the market for Sigmas essentially
> collapsed despite Honeywell agreeing to buy the carcass of the business.
> George and a partner got into the used Sigma HW business and he maintained
> a stock of HW, SW and documentation at his home in MI. More info here:

George's partner was Stan Ritland, who came from a family of doctors but who
did not like medicine as a career path himself.  They located the business in
Flagstaff to take advantage of the built in customer base made up of Stan's
three brothers; their offices were across the street from the main hospital,
and they quickly grew.

(George, an only child, met Stan when they were 8 years old.  They were best
friends for nearly 60 years, and George spent as much time at Stan's home as
at his own growing up.)

> I'm unclear on when he acquired his second home in Flagstaff, but he had a
> typical ranch style house in Flagstaff. The big difference being that he
> had installed a significantly larger electrical feed with three-phase power
> than one would find in a residence, and the downstairs family and bedrooms
> were used as the machine room in the video.

The reason George *bought* the house was that there was already a 220V service
running across the back of the property, so that running 220V into the house
was a lot less expensive than usual.

The basement in which the computers and peripherals were a tilt-up add-on to
the original house.

> I visited George in the early 2000's (I think) and at that time he had a
> fully configured Sigma-9 and Sigma-8 mainframes, along with several tape
> drives, and string of DASD. Yes, the machine room was strewn with
> printouts, docs, partially finished projects, tapes, etc. But all the
> machines worked and it was glorious. ;-)

It's a Sigma 6, not a Sigma 8.  The 6 was a clone of the 7 and 9 built for the
education market with all of the usually unbundled products included in the
license for CP-V.

> Unfortunately George passed away a few years ago. All the HW and SW that
> was in running condition was rescued by the LCM in Seattle. I know LCM has
> had someone with Sigma experience working on and off on the Sigma to get it
> running again. Not sure of the current status. But, that would be an
> awesome time-sharing system alongside the DEC-20 they have.

Not just running condition.  100,000 pounds of gear, including the 9, 6, and a
7 that had been retired in the 90s, spares for all of them, the 8 running disk
drives and 4 running tape drives, along with about 20 more disk drives (the
older 50MB hydraulic units) from the 7.  Five 24' trucks, driven by Stan and his
brothers from Flagstaff to Seattle.

My colleague Keith and I spent 3 days in Flagstaff deinstalling everything,
while Stan, 2 of his brothers, and George's wife, daughter, and granddaughter
looked on, labeled, packed, fed us, forklifted onto the trucks, and celebrated
George's life.

> There was also a group in AZ working on restoring a Sigma mainframe, maybe
> some of Georges collection. He also had a complete Sigma-7 and a boatload
> of Honeywell peripherals in his garage in Flagstaff. The AZ group was very
> energetic, but I have not heard any updates in several years. Having worked
> on CHM's first restoration, the IBM 1620, from start to finish I know its a
> huge undertaking to get even a relatively straightforward machine up and
> running.

No, George helped them, but he was running a Sigma support business; he was not
inclined to give things away.

George Plue was a true wizard.  One of his creations was a SCSI interface for
the Sigma 9 which allowed him to copy magnetic tape files to DAT (not, as we
all know now, the best choice of medium, but remarkable for all that).

George was also a true gentleman, as is Stan Ritland.  It was a privilege to
know George for the short time that I did.  We met about a year and a half
before his untimely passing, thanks to Lee Courtney.


Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134

mailto:RichA at

More information about the cctalk mailing list