diff --git a/base_classes/NXsource.nxdl.xml b/base_classes/NXsource.nxdl.xml
index 9ba824156..f53d5034a 100644
--- a/base_classes/NXsource.nxdl.xml
+++ b/base_classes/NXsource.nxdl.xml
@@ -66,18 +66,18 @@
             <item value="Broadband Tunable Light Source"/>
             <item value="Halogen Lamp"/>
             <item value="LED"/>
-            <item value="Mercury Cadmium Telluride"/>
+            <item value="Mercury Cadmium Telluride Lamp"/>
             <item value="Deuterium Lamp"/>
             <item value="Xenon Lamp"/>
             <item value="Globar"/>
             <item value="Other"/>
         </enumeration>
-    </field>
-    <field name="type_other">
-        <doc>
-             Specification of type, may also go to name.
-        </doc>
-    </field>
+		<attribute name="type_other">
+			<doc>
+				Specification of type.
+			</doc>
+		</attribute>
+	</field>
 	<field name="probe">
 		<doc>type of radiation probe (pick one from the enumerated list and spell exactly)</doc>
 		<enumeration>