allertor

[Robert Gift]

Yes, I remember now. Thanks for the picture, Peter.

The FS 2001 makes use of the motor housing cowl to form an efficient exponential channel. It pulls air from beneath and sends it out the front.

I wonder how much cancellation occurs in the Penetrator, or any other siren which pulls air in through the front, where intake air is pulled into the rotor through expelled stator output air?

[SirenMadness]

You're welcome.

Not much cancellation would occure in such a simple and high-volume drum. Cancellation occurs when the path for sound is small and has tons of straight edges.

[Archon]

here is a single tone Penetrator A P-15 that is a single phase unit


http://s139.photobucket.com/albums/q319 ... CN1355.jpg

[Archon]

Front viewhttp://s139.photobucket.com/albums/q319 ... CN1354.jpg

[Robert Gift]

Wow!
Love the size of your Penetrator rotor.
Interesting stator ports. Am curious to know why they are shaped that way.

Where do you live?
Would love to visit and help you move all that heavy stuff.
But I'm going to have you charged with 2t22 abuse.

[SirenMadness]

The ports of the stator are probably shaped that way to minimize the amount of direct hit of sound against the drum, reducing some cancellation and giving the sound a more linear flow so the sound can use up as much of its energy travelling instead of sharply alternating its path and unorganizing itself in the siren.

[Robert Gift]

When seeking the ideal, sound production, propogation, reflection and cancelation is very subtle and complicated.

Would be interesting to learn how various port openings produce sound and what characteristics they impart in waveforms.

With the best science and engineering talent, I suspect Federal Signal has determined the ideal.
If I were to make a stator port, I would copy FS's beveled openings on both sides.
But would love to know what the Penetrator's one sharp lip and one blunt lip would do.

[kagome122885]

I would like to know when the allertor was discontinued, any of you know?

[kuhlman3737]

This is a good recording of a dual tone allertor that was recorded back on march of 2005 during an early season tornado. These allertors were replaced in the summer of 2005 by 2001's, I miss these sirens great sounding and errie during warnings.

http://media.putfile.com/Dual-Tone-Allertor

[thunderbolt1003kid]

I think the Allertor was discontinued around the early or mid 70`s. But that is just my guess,I think its pretty close though.