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Federal Signal Corporation is an American manufacturer headquartered in Downers Grove, Illinois. Federal Signal manufactures street sweeper vehicles, public address systems, emergency vehicle equipment, and emergency vehicle lighting. The company operates two groups: Federal Signal Environmental Solutions and Federal Signal Safety and Security ...
Federal Signal Modulators (also known as Modulator Speaker Arrays) are electronic warning devices produced by Federal Signal Corporation that are used to alert the public about tornadoes, severe weather, earthquakes, fires, lahars, tsunamis, or any other disaster. They are identified mostly by their distinctive stacked "flying saucer" design.
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3,000 GHz (3 THz).Electromagnetic waves in this frequency range, called radio waves, are widely used in modern technology, particularly in telecommunication.
This siren is similar to Federal Signal's Thunderbolt series. Only a single unit remains in service in Milwaukee, WI. Screamers Electro-Mechanical 2, 5, 7.5, 10 8, 9, 9/12, 10/12 1968–1994 Omni Directional 102–115 dB at 100 ft. Series of small vertical sirens, comparable to Federal Signal Corporation's vertical sirens. Sentry 95
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency [1] range from around 20 kHz to around 300 GHz.
The pulse-repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of ...
SiraTone was a brand of electronic outdoor warning sirens produced by Federal Signal Corporation which began production in the early 1980s. These sirens were designed to broadcast high-intensity warning signals over a large area.
Low-frequency radio range audio signals: N stream, A stream and combined uniform tone (simulated sounds) The low-frequency radio range, also known as the four-course radio range, LF/MF four-course radio range, A-N radio range, Adcock radio range, or commonly "the range", was the main navigation system used by aircraft for instrument flying in the 1930s and 1940s, until the advent of the VHF ...