Re: missed keystrokes problem, back with a vengeance.
Hmm, sort of like sitting a couple hundred feet in the air with tons
of rocket fuel and LOX under you hoping it doesn't all blow up. Yeah,
I used to run (not own) a South Bend lathe about that size. I've got
a Microlux 7x14. Nice little digital scope, more than I can afford on
my SS. I've got a used 100 MHz Tektronix analog.
If you're seeing ringing that usually means an impedance mismatch.
You could almost think of the cables to the steppers as transmission
lines going to an antenna.
https://en.wikipedia.org/wiki/Ringing_%28signal%29 Especially the
lines going to the steppers would be suspect. But that's right, you
worked in TV, I had my FCC First Class Radiotelephone, worked in a
two-way shop.
It bothers me to see all those electronics sitting out in the open,
I'd want them in metal boxes with feedthrough capacitors. You're
mixing high powered stuff running at RF frequencies with sensitive
stuff, almost like trying to transmit and receive at the same time
like in a repeater. You're not running at microvolt levels though.
But shielding not so much in the sense of shielded wire as in sheets
of 1/16-1/8" aluminum, grounded at the mounting points, making boxes
with compartments, different circuits in different compartments. Like
an RF chassis of some sort from tube days.
http://ab1jx.1apps.com/misc/sp600_bottom.jpg The different boards
would be mounted in different compartments, including the Pi in it's
own. I'm not sure why the i386 machines work except again, shielding.
There's such a thing as a Faraday cage, a box made of metal screening,
mostly they don't work. Boxes with compartments made of aluminum
sheet or blank circuit board material do.
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