The Chrysler Air Raid Siren a product of the Chrysler Marine and
Industrial Engine Division, has been designed for use in National
Defense and to become an important part of the Nations over-all
Each Siren is a completely self-contained "Warning"
unit. Powered by a Chrysler 180 horsepower V-8 Industrial Engine,
Winterized and ready for instant operation in temperatures ranging as
low as 25 degrees F. below zero.
Each Chrysler Siren can be operated manually from a
fixed or movable location. By means of Public Utilities Circuits, a
series of Chrysler Sirens can be Remote Controlled from a Central point
as part of a "Warning" system. Should there be a power interruption,
each Chrysler Siren can continue to operate as a manually controlled
unit, independent of the system.
The Chrysler Industrial Engine drives the Siren
Compressor unit, which consists of a three stage centrifugal Air
Compressor and a high speed six blade "Chopper". The sound is created by
interrupting the flow of air delivered by the Compressor, as it passes
through the six ports into the six exponential type horns. The velocity
of the air is approximately 35,000 feet per minute, the equivalent of
400 miles per hour. The enormous sound wave has an amplitude of 138
Decibels, at 460 Cycles, 100 feet from the throat of the Compressor.
The complete power and sound unit is mounted on a
turntable that rotates 360 degrees at one and one-half. revolutions per
minute, giving a complete circle sound coverage for the "Warning" and
"All Clear" Signals.