The theremin, a device for detecting fingers using capacitative coupling, was patented in 1928. It output an analog audio signal, where pitch indicated proximi

The theremin, a device for detecting fingers using capacitative coupling, was patented in 1928. It output an analog audio signal, where pitch indicated proximity of one hand, and volume indicated proximity of the other. The children's game Operation used an effective means to detect when the game's forceps contact the metal chassis. Can we assume that the difficult and novel part of the invention is not generating the sensor signal, but acting upon it quickly enough?