At the Polo Grounds, the New York Giants become the first team to use a public address system.
On July 5, 1929 At the Polo Grounds, the New York Giants become the first team to use a public address system.
Source
Baseball Reference July 5
On July 5, 1929 At the Polo Grounds, the New York Giants become the first team to use a public address system.
Source
Baseball Reference July 5