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ACA Cyclone
History The ACA Cyclone was designed by James E. Biersach of Alerting Communicators of America and presented at a Civil Defense convention in November 1968. It was originally rated at 120dB at 100 feet, but was eventually redesigned to the point of reaching 125dB at 100 feet. It utilizes a 40 HP motor (120) or 50 HP motor (125) due to the drag-heavy rotor design. The rotor consists of a "double intake" design, which is believed to have been inspired by Federal's 500 SH-TT siren rotor. The first version, the 1968 Cyclone 120, had both rows of ports angled downwards. Like some of the other 1968 ACA siren designs, it was changed shortly after to improve performance. These improvements included a new, simple intake, and most notably the top row of ports being straightened out, as to direct the low tone outwards for maximum range while projecting the high tone downwards to the immediate area. At some point afterwards we also saw the use of the long, curved intake as seen on their 3 sig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Signal Corporation
American Signal Corporation (ASC) is an outdoor warning siren and mass notification company in the United States. ASC was founded in 1942 as Biersach and Niedermeyer (B&N). After performing poorly, the company reformed as The Alerting Communicators of America (ACA) in 1967 and expanded the line of warning systems they produced. In 1992, ACA went bankrupt and was bought and reformed as the American Signal Corporation. History The company began as Biersach and Niedermeyer Co. in 1873 as a metal fabricating operation based in Milwaukee, Wisconsin. After the 1941 attack on Pearl Harbor, concerns surfaced that the public should be notified in the event of air attacks. The United States Department of the Army granted the company a contract to manufacture outdoor warning sirens, and in 1942, the company began production of over 2,000 sirens to be installed throughout the Pacific Theater for American troops and Air Bases. The need for these outdoor warnings increased during the follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civil Defense
Civil defense ( en, region=gb, civil defence) or civil protection is an effort to protect the citizens of a state (generally non-combatants) from man-made and natural disasters. It uses the principles of emergency operations: prevention, mitigation, preparation, response, or emergency evacuation and recovery. Programs of this sort were initially discussed at least as early as the 1920s and were implemented in some countries during the 1930s as the threat of war and aerial bombardment grew. Civil-defense structures became widespread after authorities recognised the threats posed by nuclear weapons. Since the end of the Cold War, the focus of civil defense has largely shifted from responding to military attack to dealing with emergencies and disasters in general. The new concept is characterised by a number of terms, each of which has its own specific shade of meaning, such as ''crisis management'', '' emergency management'', ''emergency preparedness'', ''contingency planning' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclone Rotor
In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. The largest low-pressure systems are polar vortices and extratropical cyclones of the largest scale (the synoptic scale). Warm-core cyclones such as tropical cyclones and subtropical cyclones also lie within the synoptic scale. Mesocyclones, tornadoes, and dust devils lie within smaller mesoscale. Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base of the tropical upper tropospheric trough during the summer months in the Northern Hemisphere. Cyclones have also been seen on extraterrestrial planets, such as Mars, Jupiter, and Neptune. Cyclogenesis is the process of cyclone formation and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civil Defense Siren
A civil defense siren, also known as an air-raid siren or tornado siren, is a siren used to provide an emergency population warning to the general population of approaching danger. It is sometimes sounded again to indicate the danger has passed. Some sirens, especially within small towns, are also used to call the volunteer fire department when needed. Initially designed to warn city dwellers of air raids in World War II, they were later used to warn of nuclear attack and natural destructive weather patterns, such as tornadoes. The generalized nature of sirens led to many of them being replaced with more specific warnings, such as the broadcast-based Emergency Alert System and the Cell Broadcast-based Wireless Emergency Alerts and EU-Alert mobile technologies. A mechanical siren generates sound by spinning a slotted chopper wheel to interrupt a stream of air at a regular rate. Modern sirens can develop a sound level of up to 135 decibels at . The Chrysler air raid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sirens
Siren or sirens may refer to: Common meanings * Siren (alarm), a loud acoustic alarm used to alert people to emergencies * Siren (mythology), an enchanting but dangerous monster in Greek mythology Places * Siren (town), Wisconsin * Siren, Wisconsin, a village * Siren Bay, Victoria Land, Antarctica * Siren Rock, Ellsworth Land, Antarctica People * Siren (surname) * Siren, stage name of female bodybuilder Shelley Beattie on the TV show ''American Gladiators'' * Siren, stage name of Valerie Waugaman on the 2008 revival of ''American Gladiators'' * Alexander Brandon (born 1974), American musician, known as "Siren" in the demoscene * Siren Sundby (born 1982), Norwegian Olympic sailor Animals * ''Siren'' (genus), a genus of aquatic salamanders in the family Sirenidae * ''Hestina'', a genus of brush-footed butterfly commonly called sirens * Sirenia, an order of aquatic mammals including dugongs and manatees * Sirenidae, a family of aquatic salamanders Arts, entertainment, and m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1968 Introductions
The year was highlighted by protests and other unrests that occurred worldwide. Events January–February * January 5 – " Prague Spring": Alexander Dubček is chosen as leader of the Communist Party of Czechoslovakia. * January 10 – John Gorton is sworn in as 19th Prime Minister of Australia, taking over from John McEwen after being elected leader of the Liberal Party the previous day, following the disappearance of Harold Holt. Gorton becomes the only Senator to become Prime Minister, though he immediately transfers to the House of Representatives through the 1968 Higgins by-election in Holt's vacant seat. * January 15 – The 1968 Belice earthquake in Sicily kills 380 and injures around 1,000. * January 21 ** Vietnam War: Battle of Khe Sanh – One of the most publicized and controversial battles of the war begins, ending on April 8. ** 1968 Thule Air Base B-52 crash: A U.S. B-52 Stratofortress crashes in Greenland, discharging 4 nuclear bombs. * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
