Footnotes from Chapter 4     Footnote 3, pg. 70 Surge and ground loop problems are reviewed by Dan Fritz, "Keeping Your Shop On-Line," Modern Machine Shop, March 1995, 104-109. See also Section 7.9 in the CNC Toolbox.       This reference is no longer available on-line. Check the stacks at any major public library.     Find other Modern Machine Shop Magazine (MMS) articles                     Please visit often, more content coming for the CNC links and exercises.