On Tue, Oct 13, 2015 at 11:25 AM, Paul Koning <paulkoning at comcast.net> wrote:
There are all sorts of oddball printing technologies
from back then. I remember
one (from a lab instrument, not a printer or terminal) that used aluminum-coated
paper, but the coating was on the back of the paper. The writing was done with
a high voltage electrode just as you describe, but the result was that the sparks
would scorch the paper and leave a thin black mark.
That reminds me of a printer I worked with in 1986 or so, but this one
had multi-layer paper that could be selectively burned for true
16-level grey-scale printing. It was expensive, but the customer
needed to render ultrasonic scans in high fidelity, and even a laser
printers wouldn't work in this application because the sample
size/pixel size was too small for that to be effective.
These days, an inkjet printer could probably dither small enough black
dots to be a cost-effective alternative, or perhaps a 1200dpi laser
printer.
-ethan
I don't remember what the VT55 used. Tony's comment does sound plausible; I
distinctly remember "electrolytic" printing technology though no details. I
wonder if it might help to take a bit of the paper to a competent chemist for analysis, to
find out what the active ingredient is. That might help give a clue what is needed to
make it work.
paul