X-Y graphic plotter - an elegant solution to the problem of how to make your own graphics printer

Photo 1. No, this is not a giant pen, it is a minia- ture XY plotter. The heat- sensitive paper used is 9 cm wide. Most of us would never even cosider the idea of building an XY plotter or a matrix printer with a Centronics input. That, however, is exactly what this article proposes: a combined XY plotter and matrix printer. Probably the most important point is that you do not have to be a genius with your hands to construct the mechanical section. Not only that, but the electronics is straightforward and the cost of the design is not prohibitive. The concept of this d.i.y. project is made possible by the availability of the entire printer mechanism, complete with two bi-directional motors that drive a thermal print-head. All that remains is to fix all this in place with four small bolts. The circuit is quite simple, consisting of the Centronics interface, an input data buffer, and a character generator. The software included provides the means of drawing vectors point-to-point wi...