Both the GT40 and HP9100 were vector displays, too :-). (Although to get "vector graphics" on the 9100 you need the optional X-Y pen plotter.) The HP9100 is a very nice "personal compute machine", and the example I inherited was once used to compute the original space probe "slingshot" trajectories by Van Allen at the University of Iowa. -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927