Originally Posted by howardcano

Yes, the new MRT PTX20(NS) does work on old and new decoders. But it is not a hybrid.

A hybrid transmits both old and new data formats alternately (the new format is the one with temperature, etc.) so it will function on both old and new decoders.

The MRT is an update on their existing transponder that makes it indistinguishable from an old AMB, which the new Mylaps decoders still accept as valid. It transmits only the old data format.

If MRT has done a good job (this time!) of replicating the old AMB transponder signal, then the only way that MyLaps can exclude them again is by updating their decoder software to no longer accept the old AMB transponders.