[GreenKeys] paper tape variants
Randy and Sherry Guttery
comcents at bellsouth.net
Wed Aug 12 15:05:20 EDT 2009
John Nagle wrote:
> There was also metalized Mylar tape, a material like Tyvek, used
> for long wear in endless loop applications like early numerical
> controlled machine tools. This was hard on punches but lasted longer
>
> in readers.
Black paper tape were what we used for the SINS computers on the boomers
- which loaded their programs via an optical tape reader. The paper
tapes were fairly fragile, esp as fast as they went through the readers.
Anything went wrong - and you had a mile of very fine accordion folded
paper. Actually - accordion folded was how the tapes were stored anyway
- but the folds were something like 8 inches or so. The tapes came
"pre-folded" in boxes - and quite blank. On the tender - we had a set
of Frieden tape machines - a reader and two punches. A Mylar master was
fed through the reader - and one or two copies were punched. Once
punched - we'd load them into one of our computers on the test bench -
which would verify that the tape was a good copy.
Here are some pix of this equipment...
http://tendertale.com/tttj/tttj2-5.html 3rd picture down the
right-hand side - Verdan test bench.
For the curious - scroll on down and check out the technology of the
1950s -- the U.S. Navy's *first* deployed fully solid-state system.
Yes, compared to today's computers -even a pocket calculator is far
faster, etc. - BUT - even today - a standard (all) digital computer
cannot do what these machines did (and still do - there are still some
in use). It was their analog "capacity" that made it possible... and
that is what is so staggering.
Back to tape... there was no storage on these computers in the sense we
think of today - the disk was the arithmetic unit - nothing stored
outside of the task at hand. So any/all programs you wanted to run -
whether navigating, diagnostic, or whatever - had to be loaded from tape
- then executed. So there were a lot of tapes. John mentioned how tough
the mylar tape was... We would occasionally get updates for a program
tape - and we would destroy the old master tape (unless it was a nav
program tape - then it had to be sent "somewhere" for disposition). One
day some guy got the bright idea to run a master through a punch - with
the reader "locked" into sending with no tape in the read head... which
of course sends all holes... The punch lasted a few minutes before it
started sounding real bad - and before anyone could shut it down - it
locked up solid - with parts now where they weren't just a couple of
minutes earlier. His day didn't go so well after that... I wouldn't
recommend running mylar through your teletype... The Friedens were
heavy duty tape duplication equipment... and didn't do too well with
the "extra" challenge...
--
randy guttery
A Tender Tale - a page dedicated to those Ships and Crews
so vital to the United States Silent Service:
http://tendertale.com
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