- The Acousticon Model 28, a single microphone carbon bearing hearing aid, consists of a bone conduction headpiece with band, and amplifier. It was made by the Dictograph Products Company, Inc., in New York City, in 1928. This example was donated to the Smithsonian in 1939.
- Ref: Kelley M. Turner and Norton W. Johnston, “Carbon-Ball Transmitter,” U.S. Patent 844,635 (Feb. 19, 1907), assigned to General Acoustic Co.
- Currently not on view
- Object Name
- hearing aids
- Other Terms
- Dictograph Products Company
- overall: 3 1/2 in x 1 in; 8.89 cm x 2.54 cm
- ID Number
- catalog number
- accession number
- Credit Line
- Dictograph Products Company, Inc.
- See more items in
- Medicine and Science: Medicine
- Data Source
- National Museum of American History
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