Quote Originally Posted by Al_The_Man View Post
I will see if I can find it, the PI uses the motor and the scale the D IIRC.
Looks like it is the last video under Tuning.
Online Videos | Galil
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Al.
Argh. I hate that. But with the title of the video in hand, a little google-fu brings us to:
Two Feedback Loops are Better Than One | Machine Design

and I've used that to update my page at:
techref.massmind.org/techref/io/servo/index.htm

Turns out it's PD inside and I outside.