define af_demag with start_amplitude instead of slope
define af_demag with start_amplitude instead of slope

USGSDenverPychron/pychron,USGSDenverPychron/pychron,UManPychron/pychron,NMGRL/pychron,USGSDenverPychron/pychron,NMGRL/pychron,UManPychron/pychron,NMGRL/pychron,UManPychron/pychron,NMGRL/pychron,UManPychron/pychron,USGSDenverPychron/pychron