Was that the plotter with the 4 colour biro refils
It sure was! It drew one colour at a time.
The down-side was that it wasn't long before the pens dried out.
That youtube-video/plotter looks, so cool now!
Pity that the pens would run out too quickly and maybe expensive and/or hard to obtain, these days.
I just love the way it plots out the schematic. The noise it makes is pretty fantastic as well.
I guess the modern day printers (especially Laser), whereby it comes out almost instantly (maybe 3 seconds per page, on a middle of the road, laser printing single sided, with lots of pages at the same time) and silently (in comparison).
I suppose I would get fed up with it, after a while, and go back to modern printers. I pity you, that you sold the lot for $50 a while ago. That's life I guess.