There was a guy who came in the shop awhile back (I wasn`t there that day but the other guys told me about it) with a machine he made that worked on the same principle. It worked with regular needles and tubes though.
With his program you could program the machine to work in pulses (like morse code) not that you would need or want to, but it`s still cool.
I contacted him and asked for some pics and such, but he said he won`t show it around anymore until it`s "ready".