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Dr. Martin Cooper of Motorola, made the first US analogue mobile phone call on a larger prototype model in 1973.
On April 3, 1973, Motorola employee Dr. Martin Cooper placed a call to rival Joel Engel, head of research at AT&T's Bell Labs, while walking the streets of New York City talking on the first Motorola DynaTAC prototype. Motorola has a long history of making automotive radio, especially two-way radios for taxicabs and police cruisers.
In 1978, Bell Labs launched a trial of first commercial cellular network in Chicago using AMPS