What was Bell's immediate technical objective in the early 1870s before focusing on voice transmission?

Answer

Creating a 'harmonic telegraph'.

Bell's initial technical step involved designing a harmonic telegraph, a device intended to send several telegraph messages simultaneously over one wire using distinct musical tones based on sound wave understanding.

What was Bell's immediate technical objective in the early 1870s before focusing on voice transmission?
inventionAlexander Graham BellTelephoneinventorgoal