diff --git a/libraries/Filter/HarmonicNotchFilter.cpp b/libraries/Filter/HarmonicNotchFilter.cpp
index 9bf70e04b1..f45a2b11e9 100644
--- a/libraries/Filter/HarmonicNotchFilter.cpp
+++ b/libraries/Filter/HarmonicNotchFilter.cpp
@@ -338,6 +338,7 @@ void HarmonicNotchFilterParams::save_params()
     _attenuation_dB.save();
     _harmonics.save();
     _reference.save();
+    _freq_min_ratio.save();
 }
 
 /*