diff --git a/src/main/common/filter.c b/src/main/common/filter.c
index 9b729cd5c3..ef2d624512 100644
--- a/src/main/common/filter.c
+++ b/src/main/common/filter.c
@@ -44,7 +44,7 @@ FAST_CODE float nullFilterApply(filter_t *filter, float input)
 
 // PT1 Low Pass filter
 
-float pt1FilterGain(uint16_t f_cut, float dT)
+float pt1FilterGain(float f_cut, float dT)
 {
     float RC = 1 / ( 2 * M_PI_FLOAT * f_cut);
     return dT / (RC + dT);
diff --git a/src/main/common/filter.h b/src/main/common/filter.h
index f4de43d17d..5bc1a045b1 100644
--- a/src/main/common/filter.h
+++ b/src/main/common/filter.h
@@ -76,7 +76,7 @@ float filterGetNotchQ(float centerFreq, float cutoffFreq);
 void laggedMovingAverageInit(laggedMovingAverage_t *filter, uint16_t windowSize, float *buf);
 float laggedMovingAverageUpdate(laggedMovingAverage_t *filter, float input);
 
-float pt1FilterGain(uint16_t f_cut, float dT);
+float pt1FilterGain(float f_cut, float dT);
 void pt1FilterInit(pt1Filter_t *filter, float k);
 void pt1FilterUpdateCutoff(pt1Filter_t *filter, float k);
 float pt1FilterApply(pt1Filter_t *filter, float input);
diff --git a/src/test/unit/common_filter_unittest.cc b/src/test/unit/common_filter_unittest.cc
index e8abf37965..08d6762b84 100644
--- a/src/test/unit/common_filter_unittest.cc
+++ b/src/test/unit/common_filter_unittest.cc
@@ -41,15 +41,15 @@ TEST(FilterUnittest, TestPt1FilterInit)
 
 TEST(FilterUnittest, TestPt1FilterGain)
 {
-    EXPECT_FLOAT_EQ(0.999949, pt1FilterGain(100, 31.25f));
+    EXPECT_FLOAT_EQ(0.999949, pt1FilterGain(100.0f, 31.25f));
     // handle cases over uint8_t boundary
-    EXPECT_FLOAT_EQ(0.99998301, pt1FilterGain(300, 31.25f));
+    EXPECT_FLOAT_EQ(0.99998301, pt1FilterGain(300.0f, 31.25f));
 }
 
 TEST(FilterUnittest, TestPt1FilterApply)
 {
     pt1Filter_t filter;
-    pt1FilterInit(&filter, pt1FilterGain(100, 31.25f));
+    pt1FilterInit(&filter, pt1FilterGain(100.0f, 31.25f));
     EXPECT_EQ(0, filter.state);
 
     pt1FilterApply(&filter, 1800.0f);