Size of this preview: 453 × 600 pixels. Other resolutions: 181 × 240 pixels | 604 × 800 pixels.
Original file (604 × 800 pixels, file size: 111 KB, MIME type: image/jpeg)
 | This is a file from the Wikimedia Commons. Information from its description page there is shown below. Commons is a freely licensed media file repository. You can help. |
Summary
| Description | 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 Baran Park and surrounding areas in Milwaukee, WI to the threat of tornadoes. |
| Date | 18 February 2006 (original upload date) |
| Source | Transferred from en.wikipedia to Commons. |
| Author | The original uploader was Thunderbolttactical at English Wikipedia. |
Licensing
|
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License. |
  
|
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. | |
| ||
| This licensing tag was added to this file as part of the GFDL licensing update. |
Original upload log
The original description page was here. All following user names refer to en.wikipedia.
- 2006-02-18 03:55 Thunderbolttactical 604×800×8 (113234 bytes) This is a Thunderbolt 1000/1000T (Either is visually indistinguishable), mainly used for Civil Defence purposes during the Second World War. Some have fallen into a state of disrepair, some were decomissioned and replaced with modern tornado sirens and so
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 11:50, 19 April 2007 | | 604 × 800 (111 KB) | Liftarn | {{Information |Description=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. |
File usage
The following pages on the English Wikipedia use this file (pages on other projects are not listed):
