modified the get tracking code to make it less better. amd more tolerant of lunar speeds, taken from Nasa and other sources (Info from David Richards)

Meade.net.Telescope/Meade.net.Telescope.csproj

@@ -128,6 +128,7 @@
     <Compile Include="Clock.cs" />
     <Compile Include="ComparisonResult.cs" />
     <Compile Include="DoubleExtensions.cs" />
+    <Compile Include="ExtensionMethods\DoubelExtensions.cs" />
     <Compile Include="IClock.cs" />
     <Compile Include="StringExtensions.cs" />
     <Compile Include="Telescope.cs" />
@@ -187,6 +188,7 @@
       <Name>Meade.net</Name>
     </ProjectReference>
   </ItemGroup>
+  <ItemGroup />
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <PropertyGroup>
     <PreBuildEvent>

Meade.net.Telescope/Telescope.cs

@@ -2643,25 +2643,20 @@ namespace ASCOM.Meade.net
 
                 rate = rate.Replace("+",  string.Empty);
 
+                var rateDouble = double.Parse(rate);
+
                 DriveRates result;
 
-                switch (rate)
-                {
-                    case "60.1":
-                        result = DriveRates.driveSidereal;
-                        break;
-                    case "60.0":
-                        result = DriveRates.driveSolar;
-                        break;
-                    case "57.9":
-                        result = DriveRates.driveLunar;
-                        break;
-                    default:
-                        result = DriveRates.driveKing;
-                        //If this is ever returned it is representing a fail condition.
-                        break;
-                }
-                
+                if (rateDouble.Equals(60.1))
+                    result = DriveRates.driveSidereal;
+                else if (rateDouble.Equals(60.0))
+                    result = DriveRates.driveSolar;
+                else if (rateDouble.Between(57.3, 58.9))
+                    result = DriveRates.driveLunar;
+                else
+                    //If this is ever returned it is representing a fail condition.
+                    //result = DriveRates.driveKing;
+                    throw new ASCOM.InvalidValueException($"{rate} is not a supported tracking rate for meade mounts");
 
                 LogMessage("TrackingRate Get", $"{rate} {result}");