"Anne & Lynn Wheeler" <lynn@[EMAIL PROTECTED]
> wrote in message
news:445AB367.6060306@[EMAIL PROTECTED]
> the sounds of 2321 at boot/ipl was something like whirl, kerchunk,
> kerchunk, whirl, .... as it went thru reading volsers.
As often as not for us, it was more like whirl, kerchunk,
clatter-tick-tick-clatter, kerchunck, whirl, kerchunk,
clatter-tick-tick-clatter, kerCRUNCH with lots of red lights.
The way it worked was that each strip had a pair of tabs on top denoting
its
position within the slot in the bin. When a given strip was desired, two
sets of fingers came down and pulled the ones on either side of it away,
leaving the selected strip sticking up. The read/write drum had a pair of
fingers on its outer surface, and it was rotated such that the fingers
came
down and grabbed the strip. Then the drum reversed direction and spun for
the read/write process. When reading and writing was done, the drum
simply
stopped and reversed direction with the idea that it would throw the strip
back into the same slot whence it came. Sometimes it actually worked.
When
it did, the fingers on the drum released the strip and were retracted back
into the surface of the read/write drum.
When it didn't work, the strip, with your precious data on it, was almost
always as neatly pleated as one could hope for. There's a good
possibility
that some of the fingers got bent in this process as well, because the
pleating resulted from the strip landing on the selection fingers instead
of
in the hole the selection fingers were trying to maintain.
Another point: if any of the red lights came on, the operators *could
not*
get into the device to get what remained of the data out. Took a
2321-trained engineer to unlock the door, and he usually had to
disassemble
the picking and head mechanisms to get what remained of the crunched strip
out (which usually had a very neat accordion pleat by this point), which
explains why we had one either directly on site or available within half
an
hour 24/7 ...
In our case the "whirl, kerchunk, clatter-tick-tick-clatter, kerchunk"
sequence was repeated *twice* for every access to a master record in our
*batch* daily processing. We used to condense it as
"pick-turn-pick-turn-pick-turn-pick-turn-pick-CRUNCH". Captures the pace
at which we were accessing this device better.
-Chuck Stevens
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