Memphis, TN
Memphis, Tennessee maintains a system of 109 outdoor warning sirens. They include Federal Signal Thunderbolts and 2001s, ACA P-10s, P-15s, and P-50s, ASC T-128s, a Whelen WPS-2910, a BNCO Mobil Directo, a Sentry 20V2T [needs citation] and a W.S. Darley Weatherproof Champion. Memphis is believed to have one of the most diverse operational siren systems in the country. The sirens are tested each Wednesday at 3:30pm in Alert.
History
The first siren installed in Memphis was the single tone Biersach & Niedermeyer BN44E Mobil Directo located atop East High School on Poplar Avenue, which still runs today. Despite popular misconception, the siren is a factory-built 8-port BN44E and is not a converted engine-driven unit.