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Re: IBM's 96 column punch card (was System/3)?

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On 2016-04-15, Quadibloc <jsavard@ecn.ab.ca> wrote:

> Nobody ever took advantage of the IBM principle of moving the letters
> sideways to allow a line printer to print with proportional spacing.
> I find that a pity.

It's an interesting idea, but the technology wasn't up to it.  First of
all, it was hard enough to get the timing right for fixed-pitch spacing.
I don't think the CEs would enjoy the kind of fiddling with printer
adjustments that you'd need to get proportional spacing to look decent.
Secondly, the kind of typefaces that use proportional spacing are
detailed enough that you wouldn't be able to read them too well given
the resolution of line printers of the day.  Remember, you're working
with a fabric ribbon; if you look closely at a printout you can sometimes
almost see the weave.  Furthermore, the paper quality usually wasn't
high enough to accept such detailed impressions.  If you can find an
old printout, take a good close look at it.  Even on an IBM 1403 -
the gold standard of the day - the edges of the characters aren't
perfectly sharp.

Oh, and I almost forgot... these printers have one hammer for each
print position (typically 132 across).  Each hammer fires when the
proper character comes opposite it.  (Some printers cut costs by having
double-width hammers, each handling two adjacent print positions.
You'd need two passes to print a line: odd-numbered positions on one
pass, even-numbered on the next.)  With proportional spacing you'd
wind up with characters spanning two hammers.  As it is, the CEs were
working with timing in the tens of microseconds - tweaking this for
proportional spacing would likely exceed the limits of mechanical
engineering of the time, at least at a price that anyone would
be willing to pay.

Even if you could build such a printer that would stay in alignment
for more than 5 minutes, you'd need a boatload of electronics to
control it - and electronics was expensive back then.  It would also
run so much slower that you'd be better off just having a secretary
type your letter on a Selectric.

And I'd hate to think of the programming that would be involved.
We had to work hard enough to squeeze code into memory as it was.

For your typical company grinding out invoices or statistical reports,
it just wasn't worth it.

As for moving letters sideways, IBM wasn't the only one to do so.
The Univac 9300 used an oscillating typebar similar to that on the
IBM 1443.  Later models from various manufacturers used an embossed
band, much like the blade of a band saw running horizontally.

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Re: IBM's 96 column punch card (was System/3)? Quadibloc <jsavard@ecn.ab.ca> - 2016-04-15 07:09 -0700
  Re: IBM's 96 column punch card (was System/3)? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2016-04-15 17:20 +0000
    Re: IBM's 96 column punch card (was System/3)? scott@slp53.sl.home (Scott Lurndal) - 2016-04-15 19:03 +0000
    Re: IBM's 96 column punch card (was System/3)? Peter Flass <peter_flass@yahoo.com> - 2016-04-15 15:24 -0400
    Re: IBM's 96 column punch card (was System/3)? Walter Bushell <proto@panix.com> - 2016-04-17 10:44 -0400
      Re: IBM's 96 column punch card (was System/3)? David Wade <dave.g4ugm@gmail.com> - 2016-04-17 17:57 +0100
  Re: IBM's 96 column punch card (was System/3)? Anne & Lynn Wheeler <lynn@garlic.com> - 2016-04-15 10:39 -0700

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