Has there ever been a team that was caught using a receiver/speaker in a quarterback's helmet connected to an assistant coach's radio transmitter sitting in a box seat? It seems that a coach could use a key word on a field location with an open receiver, maybe deep 1, deep 2 and deep 3 for the 3 hashmark divided areas of play. I've seen pass plays where the quarterback suddenly spins and throws a blind pass to a spot like that when you have no idea the quarterback is even looking that way. No doubt there are receivers that small that would work. Do the officials check the helmets during a game?