> That sounds correct. Versatec made printers that used that process, I used > one > (attached to the CDC 6500 at U of Illinois PLATO). Very nice for continuous > roll > full bitmap graphics.
The Versatec electrostatic plotters are not the same as the VT52 printer, they are yet another process. WIth those the paper passes between a set of electrodes that build up a charge image on the paper. I beleive the paper is specially treated to make it more resistive so the charge doesn't leak away too quickly, and there is a clever multiplexing scheme for the electrodes to reduce the number of HV drivers needed (IIRC there is around 600V between the electrodes on the 2 sides of the paper. The paper then passes over a stream of liquid toner, which is attracted to the charge image. The liquid evaporates leaving the toner on the paper. That's it, no further processing. FWIW, apart from the Tektronix photgraphic one, I have examples of all the printers mentioned (aluminium-coated paper, Olivetti Sparkjet, Versatexc, VT52 copier) here. Some need minor repairs, but I will get them all going. -tony
