chain printer speed? - test-drb@ccmp.vtda.org

14 Jun 2006

On 14 Jun, 2006, at 05:23, cctech-request at classiccmp.org wrote:

...
  Maybe it's a trick of the eye, but the old drum
printers often  
 exhibited a
 lot of vertical misalignment of characters, making for wavy lines  
 and very
 annoying reading.  Curiously, the horizontal misalignment of  
 characters in
 chain, train and band printers didn't seem to matter nearly as much.

 I remember that the Univac 1108 hardware manuals were drum printed  
 and then
 reproduced and were darned near illegible after a couple of hours of
 miserable reading.  By comparison, 1403 output was pristine. 
Was it because of poor maintenance? My drum printer has not actually  
printed anything
for a decade or more, though as of April it can now feed paper  
instead of making burning
smells from the sprag magnet solenoids. IIRC there is some adjustment  
to the print
hammers which brings a test print into correct alignment. I've just  
looked at some old
printouts and they look OK to read, but when I look for waviness,  
there is a little there.
Its a bit like a Trinitron monitor, people used them for years and  
then asked why a
horizontal line has suddenly appeared on their screen. They often  
refused to admit it
had been there all along and they had just not noticed it.

Roger Holmes