diff --git a/user/user_config.h b/user/user_config.h
index 79a8b9f..0276ba3 100644
--- a/user/user_config.h
+++ b/user/user_config.h
@@ -15,6 +15,11 @@
 #define		MAX_CLIENTS 8
 #define		MAX_DHCP 8
 
+//
+// Set this to 1 if user_rf_cal_sector_set() is missing in your lib
+//
+#define        NO_RF_CAL 0
+
 //
 // Size of the console buffers
 //