Image:Thunderbolt1000tsrn.jpg

This photo is an image of a Federal Signal Thunderbolt (1000/1000T, Either is visually indistinguishable) with blower at the bottom of the picture. The Thunderbolt was mainly used for Civil Defence purposes during the Cold War. Some have fallen into a state of disrepair, some were decommissioned and replaced with modern tornado sirens and some were lucky enough to be maintained and are still alerting the general public to major threats. This siren is capable of producing 127dBC at 100ft or 30 metres and is most commonly available in Single Tone. Dual/fire tones were a decibel worse off to Single Tone, so Federal Signal quietly forgot about it. This siren met it's demise quite a few years later. This siren was one of the 'originals' of the Civil Defence era. The newer sirens are mainly intended for tornado warnings and other disasters, although very capable of sounding a Civil Defence warning. The other siren in this topic is an American Signal Penetrator P-50. This siren is huge (6' diameter) and is capable of pumping out 135dBc at 100ft or 30m, audible up to 10 square miles or 15 square kilometres. But still slightly 'quieter' than the very well known and feared Chryslers which belt out 138dBc at 100ft or 30m. Enough to implict severe hearing damage to within ten metres or 30 feet of the horns 'spread angle', unprotected. While the P-50 is still capable of being used for civil defence purposes, it's main intended purpose is to alert the people of Baron Park and surrounding areas in Milwaukee, WI to the threat of tornadoes.

Originally from en.wikipedia; description page is/was here.

2006-02-18 (original upload date)

Original uploader was Thunderbolttactical at en.wikipedia

Released under the GNU Free Documentation License.