diff --git a/src/main.c b/src/main.c
index 6b78f3c..bad72be 100644
--- a/src/main.c
+++ b/src/main.c
@@ -112,7 +112,7 @@ void tim2_isr(void)
 
     uint8_t alarm; // should buzzer be on?
 
-    const uint32_t minimal_value = 5; // minimal number of impulses per second
+    const uint32_t minimal_value = 2; // minimal number of impulses per second
     const uint16_t cycles_per_second = 1000;
     
     uint8_t good = (impulses[0] >= minimal_value) &&