Returning home to Brantford after six months abroad, Bell continued his experiments with his "harmonic telegraph".[N 12] The basic concept behind his device was that messages could be sent through a single wire if each message was transmitted at a different pitch, but work on both the transmitter and receiver was needed.
తన సిస్టమ్ పనిచేయడానికి, బెల్ ప్రతి కోడ్ గురించి ఏమి మార్చవలసి వచ్చింది?
pitch