Philco Radio Company, Simplex Company

In 1924, Harry Maibohm, founder of the Maibohm Motors Company, opened the Simplex Radio Company on the northeast corner of King and West Monroe in Sandusky, Ohio. Philco, one of the nation's largest radio companies, bought a controlling interest in the Simplex company in 1937. The company and its 77 employees moved to the remodeled Maibohm auto plant at 3130 West Monroe Street. Philco completed its purchase of the Simplex Company in 1944, and the plant took the Philco name in 1948. Under this new leadership, the plant started to produce new kinds of radios, based on a 4-tube design, for cars and boats, and small cabinet sets for home use.

In early 1940, the company began working on orders for various communication devices for the federal government. The plant made electronics equipment for the Army Air Corps like the SCR-535 radar, which helped to distinguish friendly planes from enemy aircraft. After World War II, the company expanded its product lines beyond radio equipment.

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