Allen Rose, writing as "Mindy Fuchs" <tomeditf(a)worldnet.att.net> wrote: As other folks have written, the pens come up on ebay sometimes. They might be OK -- HP sold them with expiration dates and I don't really know how well they keep, although (a) back in the 1980s we didn't pay much mind to the expiration date on the package and had no cause to regret it and (b) a friend who has purchased pens via ebay has said that at least some of them were OK. The pens do dry out if left in the plotter though, even if they are capped by the plotter or the pen carousel. I would not expect pens to work unless they are in sealed packages. HP no longer sells pens. Last time I looked their web site referred users to Koh-i-noor for pens and ink, and I think I managed to work out that Koh-i-noor had refillable ink pens as well as new felt-tip pens. The 7475A is tricky and you may need more than pinouts for its port, because if it's an RS-232 flavor, the DIP switches let you tell it whether to behave like a terminal device or as an eavesdropper on an existing terminal device's connection. To use it from a PC based application you probably want the former; the latter is useful for host-based graphics applications that are accessed from a terminal but know of the existence of the eavesdropping plotter. -Frank McConnell