diff --git a/TimeBaseAOMDriver/unitconversions.py b/TimeBaseAOMDriver/unitconversions.py
index aaab0568e2c0a552047f5559a30b6f2ee58f9875..d297813632f585c3921767d31b65c66637ee3a20 100644
--- a/TimeBaseAOMDriver/unitconversions.py
+++ b/TimeBaseAOMDriver/unitconversions.py
@@ -18,7 +18,7 @@
 
 from labscript_utils.unitconversions.UnitConversionBase import UnitConversion
 from labscript_utils.unitconversions.generic_frequency import FreqConversion
-# from labscript_utils.unitconversions.detuning import detuning
+from labscript_utils.unitconversions.detuning import detuning
 from numpy import log10
 
 class TimeBaseAOMDriver_AM(UnitConversion):
@@ -32,7 +32,7 @@ class TimeBaseAOMDriver_AM(UnitConversion):
 
 
 
-class TimeBaseAOMDriver_FM(UnitConversion):
+class FM(UnitConversion):
     # This must be defined outside of init, and must match the default hardware unit specified within the BLACS tab
     base_unit = "V"
     derived_units = ["Hz"]
@@ -48,6 +48,23 @@ class TimeBaseAOMDriver_FM(UnitConversion):
     def Hz_from_base(self,V):
         return self.parameters["freq"] + V/10 * self.parameters["FM_deviation"]
 
+class FM_detuning(detuning,FM):
+    """ 
+    Combination of the deuning class and FM by overwriting the base unit and only two functions,
+    to convert the FM voltage to the detuning from the atom resonance. 
+    """
+    base_unit = "V"
+    derived_units = ["MHz", "d_MHz", "linewidths"]
+    
+    def __init__(self, calibration_parameters):            
+        detuning.__init__(self,calibration_parameters)
+
+    def MHz_to_base(self, aom_frequency_MHz):
+        return self.Hz_to_base(aom_frequency_MHz*1e6)
+        
+    def MHz_from_base(self, V):
+        return self.Hz_from_base(V) * 1e-6
+
 
 class dBm_to_W(UnitConversion):
     base_unit = "dBm"