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The Vacuum Tube Age of Hearing Aids (1 janv. 1920 – 1 janv. 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.

Ajouté au bande de temps:

A Brief History of the Hearing Aid

ByBrenda Perez
28 oct. 2019
0
0
194

Date:

1 janv. 1920
1 janv. 1949
~ 29 years

Les images:

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