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The Vacuum Tube Age of Hearing Aids (jan 1, 1920 – jan 1, 1949)

Description:

Earl C. Hanson invented the vacuum tube hearing aid and named it the vactuphone. Was one of the first hearing aids that a person could wear around the ear. Technology for amplification was better than previous hearing aids, though this hearing aid required two batteries making the cost greater.

Added to timeline:

A Brief History of the Hearing Aid

ByBrenda Perez
28 Oct 2019
0
0
190

Date:

jan 1, 1920
jan 1, 1949
~ 29 years

Images:

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