diff --git a/SpectrumAWG/blacs_widget.ui b/SpectrumAWG/blacs_widget.ui
index 46c5ea936db4dcd00bf5e4189a81b03978787166..bb024d90a429e6f46d99f5119fd406c6275ae379 100644
--- a/SpectrumAWG/blacs_widget.ui
+++ b/SpectrumAWG/blacs_widget.ui
@@ -91,6 +91,9 @@
            <property name="decimals">
             <number>3</number>
            </property>
+           <property name="maximum">
+            <number>1250</number>
+           </property>
           </widget>
          </item>
          <item row="1" column="2">