[LINK] Re: to USB

Chris Maltby chris at sw.oz.au
Wed Dec 6 12:42:34 AEDT 2006


> At 01:10 PM 5/12/2006, Stewart wrote:
> > The main inhibitor in my recollection, was the sheer price of owning a
> > printer.  My first daisy-wheel was much much larger, and cost more than
> > the Apple PC with two floppy drives.

On Tue, Dec 05, 2006 at 04:15:29PM +0000, stephen at melbpc.org.au wrote:
> Yes, and very much an object of desire. I well remember seeing a pristine
> old IBM printer at auction. It was the size of a home freezer, and needed
> bright machined screw-threads the width of broom handles for some reason.
> Ah but in those days machines were machines, diesels were exotic, and none
> of your fancy-pants devices with micro-Amps and future fusion machines :-)

Heck - even the consumables were expensive. I remember UNSW computer
science going to great lengths to get ribbons re-inked until the fabric
shredded and daisy-wheels repaired. New ones were beyond the budget.

To say nothing of the risks printer designers would take to reduce
moving parts. We tried a bunch of printing terminals with a splined
rotating drum and a single narrow hammer (instead of having 8 separate
pins like the dot-matrix printers had). The hammer would stutter for
each dot as the drum rotated behind the paper - yielding a result
somewhat similar to a dot matrix printer. It all had to be fast
because they printed at around 10cps (1200 bits/sec).

The problem was that unless the whole thing was very carefully tuned
(very hard to maintain in a student laboratory) the wheel would grab
the paper as it rotated and the knife shaped hammer would tear it,
leaving a wedge shaped hole instead of a printed character. It was
all pretty rough on the ribbons too.

The noise was also phenomenal, both the high speed whine of the
drum and the clatter of the hammer, combined with the yelps from
the students as the printer chewed up another attempt to print their
assignments at the last moment.

Chris



More information about the Link mailing list