diff --git a/bindings/csharp/multicast/multicast.cs b/bindings/csharp/multicast/multicast.cs
index 8d6baa6b0..6e321cd09 100644
--- a/bindings/csharp/multicast/multicast.cs
+++ b/bindings/csharp/multicast/multicast.cs
@@ -20,6 +20,7 @@ namespace HamlibMultiCast
         }
         public class SpectrumClass
         {
+            public string Name;
             public int Length;
             public string Data;
             public string Type;
@@ -46,7 +47,7 @@ namespace HamlibMultiCast
         public string Version;
         public UInt32 Seq;
         public string CRC;
-        public SpectrumClass Spectrum { get; set; }
+        public List<SpectrumClass> Spectra { get; set; }
     }
     class Program
     {
diff --git a/bindings/csharp/multicast/test.json b/bindings/csharp/multicast/test.json
index 6f4365671..79dc30290 100644
--- a/bindings/csharp/multicast/test.json
+++ b/bindings/csharp/multicast/test.json
@@ -20,7 +20,9 @@
   }],
 
   "__comment_spectrum__": "Rigs that have spectrum output may include this data",
-  "Spectrum": {
+  "Spectra": [
+  {
+    "Name": "Sub",
     "Length": 475,
     "__comment_spectrum_data__": "2-char hex bytes so data len=2*Length",
     "Data": "00AAFF75BD2AAA...",
@@ -38,6 +40,25 @@
     "LowFreq": 14000000,
     "HighFreq": 14250000
   },
+  {
+    "Name": "Sub",
+    "Length": 475,
+    "__comment_spectrum_data__": "2-char hex bytes so data len=2*Length",
+    "Data": "00AAFF75BD2AAA...",
+    "Type": "FIXED|CENTER",
+    "MinLevel": 0,
+    "MaxLevel": 140,
+    "MinStrength": -100,
+    "MaxStrength": 0,
+
+    "__comment_spectrum_center__": "If Type=CENTER, the following fields will be present:",
+    "CenterFreq": 14267000,
+    "Span": 25000,
+
+    "__comment_spectrum_fixed__": "If SpectrumType=FIXED, the following fields will be present:",
+    "LowFreq": 14000000,
+    "HighFreq": 14250000
+  }],
   "LastCommand": {
      "ID": "MyApp 123", 
      "Command": "set_freq VFOA 14074000",