4 Jul
2001
4 Jul
'01
3 p.m.
Fred Cisin (XenoSoft) wrote:
On Tue, 3 Jul 2001, Jerome Fine wrote:
Jerome Fine replies:
Typical of a large company to try and obtain a monopoly on an idea
that is so generic. Sounds like the DEC patent on the MSCP bit.
If a mechanical reader example is one that has a
plate with 960 copper plated
raised areas over which the card was placed, then I would also need to know
how the optical mechanism functions. From what I remembered of the high
speed card readers, they usually fed the card into a slot around a curved
read area where I presume the light shone through. I would think that for the
light reader mechanism, timing would be critical.
What I learned in school 35
years ago:
Long ago, IBM patented the shape of the hole, and a few companies
attempted to build machines with round holes! But THAT is not the
issue. That patent was overturned. Then, in their ongoing efforts to mistreat the
competition, IBM patented
their brass roller. The IBM card reading system consisted of a brass
roller and a group of metal brushes. Which brush made contact was one
axis, and the rotational position of the roller was the other axis. IBM's
actions backfired. They ALMOST worked - several competitors almost went
under when they could no longer use a brass roller. Bizarre, stupid
things were tried, such as 960 plungers in a grid. Then one company
(CDC?) succeeded in what had previously been too great an engineering
challenge, and came out with an optical reader (12 photocells and a
roller). In addition to getting around the IBM patent, they also ended up
with a card reader that could be made to run much faster than the fastest
that IBM had to offer; thus bringing them back from the brink and into the
lead.
I saw the inside of one card reader which had a platform on which the
card rested while some sort of "plungers" attempted contact with 960
mountains sticking up about 1 millimetre above a bed of a non-conductive
material. Each "mountain top" was the shape of the hole and probably made
of copper which allowed for a contact through the hole (providing the chad
had been removed).
As for the CDC card reader, it definitely was MUCH faster, probably
at least 10 times the speed. The feed mechanism used air to move the
card though the slot past the photo cells. The rest of the CDC hardware
also seemed to work much better than any IBM stuff. In addition, I seem
to remember that on the UNIVAC 1107 that I used just prior to the CDC
3500 the same sort of card reader was present. What I had not realized
is that the basic design of the card reader may have come from CDC?
My experience with non-IBM hardware started around 1963 with the
UNIVAC 1107 running EXEC II is I remember correctly - a vast
improvement over what was available at the time on the IBM 7094.
Tolerance
issue? Sorry, I have no idea as to the requirements, but I often
found that the first attempt to add a character with an 029 resulted in a misplaced
punch for just the added character - so a duplicate and a second attempt
FIX THAT
PUNCH!
I have never had that problem with a properly aligned 029. But they DO
need to be aligned and adjusted occasionally.
Grumpy Ol' Fred cisin(a)xenosoft.com