The RSH-10 was a versatile multipurpose siren, and was able to be used as a civil defense siren, a fire siren, or severe weather siren. No RSL-10 units are known to exist today. Federal decided to drop the RSL-10 concept for unknown reasons, and they dropped the idea of using flattened horns in favour of a deflector to save costs, despite the reduced performance from doing so. These used flattened horns that directed the sound down towards the disc, and the same concept was used with prototypical RSH-10 as well. The shaft that connects the rotor to the gearbox at the bottom of the siren.įederal also experimented with an RSL-10 during the siren's early development, using the rotor and stator from the 7-port STL-10. Rarely, the gear reduction drive can malfunction, causing the disc to spin incredibly fast. The siren also has a 10HP AC motor on top, and was available in single and three phase, the RSH-10B and RSH-10A respectively. The disc is enclosed inside a very large metal mesh cage, which protects it from the elements. This greatly amplifies and projects the sound, allowing it to reach 122 dB at 100ft, far more than the 115 dB of a standard STH-10. Because of this, the disc rotates and coasts with the rotor like an ACA Penetrator siren. The RSH-10 makes use of Federal's STH-10's rotor and stator, but instead of using horns to project the sound, the sound is instead directed downwards, and this concentrated beam of sound is then deflected by a rotating disc deflector, which is driven at 2RPM by a 1592:1 gear reduction drive on the bottom of the disc directly attached to the rotor using a long shaft. Rather than having the rotor and stator inside of a horn that rotates, the RSH-10 instead has a stationary rotor and stator, with a separate rotating deflector. The RSH-10 makes use of a very unique design. The rotating disc is also easily visible. The siren was made in an attempt to amplify the sound of an omnidirectional siren without the need for an entire rotator assembly or horns.Ī RSH-10B with the top cover removed, showing the STH-10's rotor and stator. The Thunderbeam would be Gosswiller's last patent, as he'd retire from Federal in 1982. The siren was patented the same year, with the patent being published in 1985. The RSH-10 was designed and created by Federal's then-chief designer, Earl Gosswiller, and it was patented in 1982. RSH-10 stands for 'Rotating Single-tone High, 10 Horsepower'. The Thunderbeam was a popular siren, and its design allowed it to be much louder than its omnidirectional cousins. The RSH-10 'Thunderbeam' was a unique rotational/omnidirectional hybrid siren that was produced by Federal Signal for over a decade, replacing the earlier 500-SH.

Federal signal sth 10