System Recording, Wail / Attack - Danville, Indiana

Interesting test. Very windy day. Lots of tones on the radio but unfortunately, this siren did not go off. Fortunately, I had strategically placed myself at this location so that I could hear other sirens in addition to this one when it tested so I got a nice ambiance recording. The Vortexes start up first in wail followed by the T-128's in attack. The Vortexes were canceled after a minute or so and the T-128's stayed on for a full 3 minutes of attack. I was less than a mile from 2 Vortexes and the closest T-128 was about a mile and a half away.
Somebody that knows more about the tones used to set off sirens could correct me if I'm wrong, but I believe the FSK you're hearing set off the Vortexes, canceled them, and also was used to poll the during and after their tests. I'm not sure what you'd call the tone that set of the other T-128's, but that was the first different tone head after the FSK's started. The 2 toned tones were used to set off other sirens in the county. I'm wondering if these tones aren't sent out from a central location but rather from the local jurisdictions as I would have expected to hear more tones with the number of sirens and different systems in the county and some of the tones weren't coming through as clearly as others.
In addition to this siren, Danville is densely covered with 4 more T-128s and 4 Vortexes. Hendricks county has a mix of sirens from the big 4 siren companies, but mostly 2001's.
Hendricks county tests every Friday at 11am year round if the temperature is above 32 degrees.

[@Darcfoxx101]

I live up by a Vortex that’s located across South Elementary in Danville Indiana. I know there’s one in the Town Square, and another up by the hospital, but I haven’t seen a fourth one.

[@niks_crazy_world]

That FSK is most likely Motorola FSK, as it has the static and the beeps. Watch videos from Lake County Indiana, and the static sounds similar.

[@MidwestCWS]

Yup, very similar to Lake County. Lake County has the two pulse throughout the entire test too.