From Field Phones to 5G: The Evolution of Military Radio and Telecommunications
Field telephones were standard on the battlefield from the 1910s through the 1980s, with the EE-8 field telephone (1930s–Vietnam) offering a 7-mile range. The SCR-300 Walkie-Talkie, developed by Galvin Manufacturing (Motorola) in 1940, was the first backpack FM radio with about a 3-mile range.