diff --git a/include/if482.h b/include/if482.h
index 235f320e..ce5a3f2b 100644
--- a/include/if482.h
+++ b/include/if482.h
@@ -4,6 +4,7 @@
 #include "globals.h"
 
 #define IF482_FRAME_SIZE (17)
+#define IF482_SYNC_FIXUP (3) // calibration to fixup processing time [milliseconds]
 
 String IRAM_ATTR IF482_Frame(time_t tt);