Noise suppression mode is only applicable to ActivePro V3 / ActiveBasic V3, it is not enabled for ActivePro V3 Performance or MotorKart due to the higher demands of these transponders. 

The loop of RACE RESULT Active systems emits a 125kHz signal, which contains a series of information to identify it as a RACE RESULT loop and the Channel / Loop IDs of the system. This signal is what activates the internal processing of the Active transponders which must first process the data to check whether this is a valid RACE RESULT loop or not, before generating a passing.

All electronic devices emit electromagnetic noise on a range of different frequencies, some of these devices can emit noise on the same 125kHz frequency as used by the RACE RESULT loop. If such noise is detected by a RACE RESULT Active transponder then the internal processor will always try to decode this signal to check whether it should generate a passing. 

If a transponder is activated by a 125kHz signal which is NOT recognised as a RACE RESULT loop then this will be logged internally, if this occurs more than once between sequential valid RACE RESULT loops then the transponder will enter Noise Suppression Mode. Whilst this mode is activated the transponder will temporarily reduce the sensitivity of the 125kHz receiver, and thus will require a stronger signal to activate it again.

Noise Suppression Mode is then monitored in 10 second intervals, if the source of the noise is no longer present at the next check then the transponder will return to regular sensitivity. 

When Noise Suppression Mode is triggered then the transponder will also log a Warning Flag for high noise which will be transmitted with the next passing.

If a transponder is still activated by external noise whilst in Noise Suppression mode then this will trigger very high noise warning flag.