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1 / 1 · US patent 957,403 (1910): telephone receiver
US patent 957,403 (1910): telephone receiver·Nathaniel Baldwin·Public domain (US patent)Why it mattered
- 01
Its sensitivity made it the preferred headset of US Navy wireless operators in the WWI era.
- 02
Baldwin's company went on to make loudspeaker and headset drivers for the early radio industry.
Engineering record
- Patented design
- US 957,403 (filed July 1909, granted May 1910): a single spool winding giving the combined magnetic action of four pole pieces[1]
Original pricing
No reliable period price located
2026 equivalent
Not calculated without a reliable original price.
Public price evidence was not sufficient to publish a defensible original figure.
Use in the field
Adopted by the US Navy for wireless-telephone headsets during the First World War[2]
Manuals & original documents
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