[time-nuts] UPS for my time rack

Bill Byrom time at radio.sent.com
Mon Oct 12 22:05:06 EDT 2015


HA! That was good. I started working at Tektronix in September 1987 and
we used VAX computers in our major field offices for order processing in
the late 80's and early 90s. They batched their daily results to our
headquarters in Oregon every night on "high speed" modems on special
phone lines. We had daily and weekly backups at each office onto open
reel tape.

The UPS horror story I can relate was at a major airline underground
computer center in the 90's. I was waiting to train a group on a high
power curve tracer they had purchased to test SCR's every time one of
their UPS inverters blew up (which must have been moderately often). I
was waiting in the supervisor's office, which had two telephones. One of
the was fire engine red, which I thought was reserved for the Hot Line
with Russia in Washington. The supervisor told me that if the red phone
rang it would be a call directly from the well-known CEO of the airline.
It seems that sometime before a worker was using a large wrench (which
was not conformally coated) directly above the critical location where
the switch between the UPS output nd city power was located. When the
wrench fell it shorted the single point of failure in their system,
stopping their reservation and flight system operation systems. So the
maintenance department suddenly received a red hotline phone for the CEO
to call when the UPS failed.

Anything can (and will) fail, and as your story about the VAX improper
manual reboot shows good intentions can turn into epic fails. When I
owned a small business in the mid-80's I was contacted by a local
company in central Texas with a small VAX and CDC disk drive who had a
major failure at his data entry company. He knew he wasn't perfroming
backups so thought it was a good time to perform preventative
maintenance on the physically large CDC removable disk pack drive (with
a huge magnet and large voice coil actuator). The company owner decided
to clean the "sock" disk drive air filter, so he removed it and vacuumed
it off. 

He then made a command decision that he should use the clean side of the
filter now (since one side had been filthy) and inverted the sock filter
before reinstalling it. Gasp!! Shortly after the drive spun up a large
dust particle was sucked off the dirty side of the filter (now in the
previously clean drive chamber) and he heard a disk head bouncing around
the inside of the drive. It was (of course) the servo head. Remember
that they had no backups. 

The drive was transported to CDC headquarters and they declared it a
lost cause. The small company owner asked me (and probably others) if I
would help him strap a good drive to the bad one and fabricate an arm
between the good and bad drive head acuators so the good drive servo
track would move the bad drive heads (with other required rewiring to
get the drives to work "together"). I told him NO and walked out without
wasting my time explaining how servo tracks really worked and the
mechanical and electrical engineering fallacies in this crazy scheme.
No, I would not take a penny of his money to try any portion any of that
scheme! His company soon went bankrupt, I believe.

-- 
Bill Byrom N5BB

On Mon, Oct 12, 2015, at 01:28 AM, Bill Hawkins wrote:
> My apologies in advance for further putting tension on this OT thread,
> but one of the great stories from the early days of Usenet concerned a
> really large UPS system for a data center. In the late 80s the Digital
> Equipment Corp VAX computer was among the most powerful you could buy.
> If you can accept that amount of time travel, follow this link:
> 
> http://www.hactrn.net/sra/vaxen.html
> 
> or Google "vaxen immortal power"
> 
> The reference to October 19, 1987, is to the first computer failure to
> have a major effect on the stock market.
> 
> Enjoy, as they say
> 
> Bill Hawkins 
> 
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