ACA Cyclone

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) The topic of this article may not meet Wikipedia's notability guidelines for products and services. Please help to demonstrate the notability of the topic by citing reliable secondary sources that are independent of the topic and provide significant coverage of it beyond a mere trivial mention. If notability cannot be shown, the article is likely to be merged, redirected, or deleted. Find sources: "ACA Cyclone" – news · newspapers · books · scholar · JSTOR (September 2015) (Learn how and when to remove this message) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "ACA Cyclone" – news · newspapers · books · scholar · JSTOR (March 2010) (Learn how and when to remove this message) (Learn how and when to remove this message)

The ACA Cyclone is an electro-mechanical, omnidirectional, dual-tone outdoor warning siren produced from 1968 to 2007 by Alerting Communicators of America (ACA). Originally intended for civil defense purposes, early versions of the Cyclone are rated at 120dB from 100ft, and later models are rated at 125dB.

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 signal sirens. This allowed for an optional coding damper to be added, which produced a pulsating "local code" tone.

In 1979, ACA was experimenting with the design of the Cyclone 120 to try and get the best performance possible. This included a slightly re-designed top cover, and a ring placed around the bottom of the stator to direct the sound outwards more smoothly. In 1980, this design was scrapped, and ACA unveiled the Cyclone 125, which came fitted with a new intake, a sound dispersion cone in the intake, and most notably a parallel stator, projecting both the high tone and low tone outwards. This was further assisted by a lip or "ring" added to the top cover of the siren. At this time, ACA unveiled the Penetrator-50, a 135dB rotating siren which replaced the Hurricane 130. The P-50 reused the rotor and stator of the Cyclone 120, and was produced alongside the Cyclone 125 until the early 2000s when both sirens were discontinued in favor of more modern sirens.^[1]

This technology-related article is a stub. You can help Wikipedia by expanding it.

• v
• t
• e