20 Dec
2024
20 Dec
'24
5:35 p.m.
On 12/20/24 16:36, Van Snyder via cctalk wrote:
The IBM 1403 printer had interchangeable print chains.
I know of only
four 1403 printers still working — two at the Computer History Museum
in Mountain View, CA, one at the IBM Technology Center in Böblingen,
Germany, and one near Endicott, NY.
All four have the 48-character "A" or "Business" chain, and CHM has
a
16-character numeric chain that allows the printer to run twice as fast
for numeric-only output. CHM doesn't have an "H" or "Fortran"
chain,
and as far as I know, none of the others do. The difference is that
parentheses are % and "lozenge" — a square with indented edges
— apostrophe is @, and = is # on the "A" chain. IBM also had a 64-
character chain that included box and line drawing graphics. BTW,
nobody seems to know what "lozenge" was meant to represent.
I recall only learning once not to leave a cup of coffee atop a running
1403. I think the lozenge-character print train was mostly used on the
BCD machines like the 1401, but I could be mistaken.
I recall one of the old timers at CDC relating that try as they might,
they couldn't get a train printer of their own design without the print
train disintegrating. I believe that CDC quietly purchased a 1403 on
the gray market and took it to pieces. The result was the CDC 512. Up
until this time, the standard high-speed printer at CDC was the 501--a
drum printer.
It was interesting to note that hammer firing differences on a drum
printer resulted in characters being vertically displaced, which was
very annoying to the eye. Whereas the train printers could displace
characters horizontally and was not nearly as unsightly.
--Chuck