Early 360 machines (Was: Front panel switches - what did they do?)

Chuck Guzis cclist at sydex.com
Wed May 25 20:43:20 CDT 2016

On 05/25/2016 06:16 PM, Paul Berger wrote:

> I only ever saw one of the drum style high speed printers and I think
> it was a Honeywell wavey line printer.  I remember the operator
> demoed it for us by printing a picture, if you printed a whole line
> of the same character it would fire every hammer at the same time, it
> was very noisey.  The 1403 limited the number of hammers that could
> fire simultaneously, for testing the CEs had what was called train
> breaker routine that would exercise the printer firing the maximum
> number repeatedly.

CDC printer ribbons came packaged with a set of disposable gloves.  Good
thing, that.

One of the problems with the 501 drum printer was that hammers could get
gummed up and slow down a bit.  The "wavy line" output was typical of
this.   (similar delays on train printers would result in a lateral
displacement of a character, which for some reason, wasn't nearly as
annoying.)  One bit of entertainment for the military visitors was
either "Anchors Aweigh" or "The Stars and Stripes Forever", played using
the 1604 speaker, tape drives, and the 501 as percussion.  The 501 had a
switch for high/low speed.  If set to "low", the output wasn't half bad.

The 501 would rattle like a machine gun, but the 512 train printer would
put out an ear-splitting scream if you left the sound cover up.

The train printers did have an obvious advantage over both the drum and
band printers.  In our shop, we printed lots and lots of core dumps.
Add to a full CM dump, a couple of million words of ECS and the "0"
characters wore out pretty quickly.  You could replace a train slug, but
had to live with "fuzzy" zeroes until someone higher up couldn't stand
the printout.

I recall reading a set of pre-publication Univac 1108 manuals that were
printed on a badly-adjusted drum printer.  It gave me headaches.


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