First Electric Hearing Aid (1 gen 1898 anni – 1 dic 1898 anni)
Descrizione:
Miller Reese Hutchison creates the first electric hearing aid called the akouphone. It used a carbon transmitter in order to make the device portable. This hearing aid would amplify weak signals into strong signals using electrical currents.Aggiunto al nastro di tempo:
Data:
1 gen 1898 anni
1 dic 1898 anni
~ 11 months