I never saw anyone quite as irritable as an IBM CE who had to
replace a bad core doughnut on our 7094. They're little, and
they're very slippery when covered with oil.
We all tiptoed around him until he was done :-).
Yep. This would have been in '65 or '66. I guess a whole new
plane would have been too expensive.
BTW, the disk heads on a 7094 didn't automatically retract when
power failed. I was warned when I hired on to stay out of the
dark hall if the power failed, because the resident CE would be
charging down it to manually crank out the disc heads :-).
I've seen core memory and the TINY little donuts on it, is this what
we're talking about? PDP/8 era is all I've seen.
Heh. Dozen years or so ago or so, I was the same person charging down
the dark hallway during an outage, so I could switch off the now-crashed
systems in my lab, so I could bring 'em up in something resembling the
right order. That damn UPS caused more outages than if we hadn't had it.
This was all modern stuff, though, sadly enough.
Uh-huh. First locate the right core and mark it. Then unstring
the vertical, horizontal, and diagonal wires, thus freeing up a
bunch of good cores. Toss the bad one, add a new one, and
restring the whole #@$! mess :-).
IIRC, it took him about half a day sitting on a newspaper-
covered computer room floor in white shirt and tie, sleeves
rolled up and hands covered in oil :-).
My last manager at IBM was the engineer who figured out how to
automate weaving a core memory. Before that, core planes had been
hand-wired. Whether by hand or by machine, I always thought of
core weaving as requiring a certain amount of magic. (-:
No, I missed that one. Most of the stuff I knew about was NCR proprietary. I
apprenticed on the NCR304 in 1960, IIRC had 40K memory of 60 bit words(10
characters), used Ampex tape drives with NO inter-record gap. Printer was a
200LPM drum using 340VDC for hammers, firing a charged capacitior through a
The law of intelligent tinkering: save all the parts.
If you looked at the coding on those cards, they actually
represented two rows of paper tape, 45 columns each.
And I also remember Univac had 90 column cards even earlier, but
I don't recall the coding on those.
Wow! I thought I was the ony one that remember those stupid 96-column
cards on those old System 3's. I almost was getting the hang of
reading stupid little round holes when a new fangled CARDLESS Data
Genera was rolled in.
Actually, I miss those days. I remember when the card reader on our
S/3 was screwed and the IBM CE was in ti fix it. It was hot and he
had his long-sleeved white shirt unbuttoned at the cuff and roled up.
Things weren't going well and he was cursing and starting to press
buttons and such very hard and very fast. His sleeve unrolled and got
caught in the belts that pulled the cards through and ripped the
entire sleeve and half the shirt right off of him.
Had to be one of the scariest and funniest thing I ever saw!
Back in the days of "tabulating machines" ('56 or '57) I saw a
CE get his tie caught in a card sorter. Wrapped it till his
chin was resting on the top before it started slipping. We cut
the tie off his neck. He'd flown for the Flying Tigers in WWII
and said this scared him just about as bad :-).
We still had a shop full of them in 73 in Guantanamo, supposedly the last
one in the Navy. Ran paper reports but the civil service supply types
preferred the card decks. Lots of fun when they added 2 digits to stock
numbers and we had to generate 50,000+ new cards.
Apologies Nahmie. I have been in the business since the early 60s and
know about the round holes and the big computer company whose name is a
three letter acronym, the first of which is a Roman numeral. I was and
am being a smartass.
In all regards, I agree with you, and share your feelings for the family
We go when we're called. Not every one belives they had enough time to
'get it right'. I belive there's a plan for that...
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