RC Failsafe Trigger Update

src/modules/sensors/rc_update.cpp

@@ -228,6 +228,21 @@ RCUpdate::rc_poll(const ParameterHandles &parameter_handles)
 			/* signal is lost or no enough channels */
 			signal_lost = true;
 
+		//This problem occurs at RC controllers which are use PPM signal on RFD 868+/900 Modems (Maybe it can be also related another types) 
+		} else if (rc_input.channel_count == 16) { // check failsafe by channel values to detect RC loss (This statement is specific for only RF modules that still sending valid PPM signal when RC loss from ground RF)
+			for (unsigned int i = 0; i < 16; i++) {
+				if (i < 12 && rc_input.values[i] > 999 && rc_input.values[i] < 1005) {
+					signal_lost = true;
+
+				} else if (rc_input.values[i] == 0) {
+					signal_lost = true;
+
+				} else {
+					signal_lost = false;
+					break;
+				}
+			}
+
 		} else {
 			/* signal looks good */
 			signal_lost = false;