This pen plotter was made around 1973 and was used for creating drawings.
The plotter was
controlled by the host computer with discrete signal lines which allowed the
drum to be rotated one step and/or the pen to be moved one step. The host
computer has to do all the work of creating lines and characters using single
steps of .005, .1 mm or .01 inches depending on model. Mine is the .005 inch
model. The PDP-8/E XY8-E plotter control card M842 has a pot to adjust
the step rate. For this plotter the maximum is 300 steps per second with
.005 inch or .1 mm steps or 200 steps per second with .01 inch steps.
This is about 1.5 inches per second. Interfaces for these type of plotters
were available on omnibus (8/E) and earlier PDP-8's. This plotter used 30"
roll sprocket feed paper.
Later plotters used standard
interfaces such as serial and high level commands sets which let you send
the end points for lines and text for the plotter to draw. They could also
draw much faster, over 30 inches per second on high end plotters. The pen
plotters have pretty much been replaced by plotters which are large inkjet
printers. Modern plotters use either sheets of paper or roll paper without
sprocket feed holes.
This link has information on a IBM 1627 plotter that is a relabled Calcomp plotter that is
very similar to the Calcomp 563 plotter.
Feel free to contact me, David Gesswein djg@pdp8online.com
with any questions, comments on the web site, or if you have related equipment,
documentation, software etc. you are willing to part with. I am
interested in anything PDP-8
related, computers, peripherals used with them, DEC or third party, or
documentation.
