diff --git a/firmware/common/max2837.c b/firmware/common/max2837.c
index 5fdc2ea4..9d04f6f6 100644
--- a/firmware/common/max2837.c
+++ b/firmware/common/max2837.c
@@ -233,8 +233,8 @@ void max2837_set_frequency(max2837_driver_t* const drv, uint32_t freq)
 	div_cmp = 30000000;
 	for (i = 0; i < 20; i++) {
 		div_frac <<= 1;
-		div_cmp >>= 1;
-		if (div_rem > div_cmp) {
+		div_rem <<= 1;
+		if (div_rem >= div_cmp) {
 			div_frac |= 0x1;
 			div_rem -= div_cmp;
 		}
diff --git a/firmware/common/max2839.c b/firmware/common/max2839.c
index 868855d4..86ab0ba9 100644
--- a/firmware/common/max2839.c
+++ b/firmware/common/max2839.c
@@ -239,8 +239,8 @@ void max2839_set_frequency(max2839_driver_t* const drv, uint32_t freq)
 	div_cmp = 30000000;
 	for (i = 0; i < 20; i++) {
 		div_frac <<= 1;
-		div_cmp >>= 1;
-		if (div_rem > div_cmp) {
+		div_rem <<= 1;
+		if (div_rem >= div_cmp) {
 			div_frac |= 0x1;
 			div_rem -= div_cmp;
 		}