RE. Re. Doctor Who
Its also possible that the Arduino controlled some functions as well.
I have some experience with these, its feasible to make one do very complex realtime sensitive housekeeping tasks under control of a larger CPU eg Pi Zero without the timing overheads of the latter.
As it happens I am also planning to make a sonic device, mine will also include GaN based FET induction heater with optical and dual infrared feedback using bits from an ear thermometer found in the road.
Biting the hand that feeds IT
