Mesa THCAD

THCAD does work with incremental encoder inputs, but the mode has to be changed to just counting up or down on a single channel. With Mesa that is done by setting the encoder mode to 1 I think, not sure, so please do check that. Since using Linuxcnc on both mentioned hardware I see no reason for it not to work.

Pl7i92
Not 5000, from 15000 to 30000V for a pilot arc. I have set aside some high voltage transformers with attached electronics to do some testing when and if I do manage to get some spare time. Also found some voltage to frequency converter chips that I want to test as a THC, they should work with parallel port also even with latency of 100000 at full scale. That will be just a proof of concept, as for the price of a THCAD I would not spend the time to build one. That started before I got my hands on a THCAD, so now it is on a back burner.
Total cost for the THC would be a bit over 15$ plus the time to assemble and wire it, if not electrocuted during wiring! Also the resolution is a bit lower than THCAD.
The pilot arc start transformer thingies I will be needing to make 4 plasma cutters @35A from a Thermal Dynamics 140A I have collecting dust, it has 4 separate power sources stacked on top of each other, but they do need some other control stuff and connectors and valves etc.
To many projects, no time, I do need to sleep from time to time.

FYI, i have 2 Yamaha bikes, last few days the weather was very good, but the bikes are still parked! They both need oil change and some maintenance, so time.
THCAD is worth every peny (or cent ), especially in conjuction with Linuxcnc.