Footnotes from Chapter 3     Footnote 2, pg. 47 An interesting article on converting an old CNC to a PC is given by Mark Albert, "Software is the CNC," ...       Find Modern Machine Shop Magazine (MMS) articles:     1.) "Software is the CNC" by Mark Albert     2.) "Choosing a Retrofit CNC" by Peter Zelinsky                           Please visit often, more content coming for the CNC links and exercises.