Negative, not positive.

fscomm/preferences/prefdialog.ui

@@ -796,7 +796,7 @@
          <item>
           <widget class="QTabWidget" name="tabWidget_2">
            <property name="currentIndex">
-            <number>1</number>
+            <number>0</number>
            </property>
            <widget class="QWidget" name="tab_5">
             <attribute name="title">
@@ -1080,7 +1080,14 @@
               </widget>
              </item>
              <item row="9" column="1">
-              <widget class="QSpinBox" name="spinESDb"/>
+              <widget class="QSpinBox" name="spinESDb">
+               <property name="minimum">
+                <number>-99</number>
+               </property>
+               <property name="maximum">
+                <number>0</number>
+               </property>
+              </widget>
              </item>
              <item row="10" column="0" colspan="2">
               <widget class="QLabel" name="label_47">