correct name for lineedit; closes #34

src/gui_qt/data/signaledit/editsignalwidget.py

@@ -46,7 +46,7 @@ class EditSignalWidget(QtWidgets.QWidget, Ui_Form):
                 stype = 'pts'
             else:
                 try:
-                    _nop = float(self.lineEdit.text())
+                    _nop = float(self.ls_lineEdit.text())
                 except ValueError:
                     _nop = 0.0
                 stype = 'time'