Am I the only one for whom this doesn’t work? If I try to unlock the car with the fob against my head, my car doesn’t seem to receive any signal. But if I try and unlock the car from the same distance, key fob not on head, it works like normal.
Hold the fob under and in contact with your chin and aim your face at your car. The beam gets focused in a specific direction when you're using your head to amplify the signal. This is how you get improved distance with your head. Your skull is not an isotropic resonant emitter. The signal ends up beam-shaped.