Patents
- US 174,465 -- Telegraphy (Bell's first telephone patent) -- Alexander Graham Bell
- US 186,787 -- Electric Telegraphy (permanent magnet receiver) -- Alexander Graham Bell
- US 474,230 -- Speaking Telegraph (graphite transmitter) -- Thomas Edison
- US 203,016 -- Speaking Telephone (carbon button transmitter) -- Thomas Edison
- US 222,390 -- Carbon Telephone (carbon granules transmitter) -- Thomas Edison
- US 485,311 -- Telephone (solid back carbon transmitter) -- Anthony C. White (Bell engineer) This design was used until 1925 and installed phones were used until the 1940s.
- US 3,449,750 -- Duplex Radio Communication and Signalling Appartus—G. H. Sweigert
- US 3,663,762 -- Cellular Mobile Communication System—Amos Edward Joel (Bell Labs)
- US 3,906,166 -- Radio Telephone System (DynaTAC cell phone) -- Martin Cooper et al. (Motorola)
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