HP-41 Extension Module - The 82143A Thermal Printer/Plotter

The 82143A Thermal Printer/Plotter

The printer used rolls of thermal paper to print lines of up to 24 characters. The thermal paper provided for a bluish printout, but was somewhat unstable, as the printout could vanish or the whole paper turn blue due to excessive heat.

The printer had some graphical capabilities, as you could design your own character shapes, or even turn on or off individual pixels. However, the buffer memory could not hold sufficient information to print a whole line in graphic mode, and you could not alter line spacing, so it was impossible to print continuous graphics. The printer nevertheless provided some printing utilities that were able to graph a function on a band of paper.