The Siren Board

After the tornadoes last week there was a discussion on a local forum about Tinker Air Force Base using the voice capability of their Modulator system for the first time during an emergency. This led to a discussion of Oklahoma City?s Whelen system and how it is utilized.

The safetycom.com website

http://www.safetycom.com/spotlights/Oklahoma_city.html#

which belongs to the company that installed the system says that the directional sirens are tone only Vortex sirens. My observation of every unit that I have seen is that the directional sirens in Oklahoma City always return to a consistent predetermined point on the compass, which causes me some confusion as to whether they are Vortex models or actually of the WPS 4000 series. The Vortex sirens in Midwest City stop oscillating when the siren is deactivated and thus can wind up pointing in any direction. They also have a fin on the back of the driver housing much like a wind vane while the Oklahoma City units lack this feature. Since Oklahoma City has, so far, not used the voice capability, I am unable to determine if the rotating sirens are voice capable or not. It seems like a waste to put the sophisticated rotator and rotator electronics on a tone only siren, especially when there are around one hundred or so in the system.

I would be curious what some of you who are familiar with Whelen think which model they actually are.

woodyrr wrote: My observation of every unit that I have seen is that the directional sirens in Oklahoma City always return to a consistent predetermined point on the compass, which causes me some confusion as to whether they are Vortex models or actually of the WPS 4000 series.

Believe it or not, the new 2001-130s in Shawnee County always seem to be pointing the same way, even though I know they have been sounded. Perhaps its just an option or something.

woodyrr wrote:After the tornadoes last week there was a discussion on a local forum about Tinker Air Force Base using the voice capability of their Modulator system for the first time during an emergency. This led to a discussion of Oklahoma City?s Whelen system and how it is utilized.

The safetycom.com website

http://www.safetycom.com/spotlights/Oklahoma_city.html#

which belongs to the company that installed the system says that the directional sirens are tone only Vortex sirens. My observation of every unit that I have seen is that the directional sirens in Oklahoma City always return to a consistent predetermined point on the compass, which causes me some confusion as to whether they are Vortex models or actually of the WPS 4000 series. The Vortex sirens in Midwest City stop oscillating when the siren is deactivated and thus can wind up pointing in any direction. They also have a fin on the back of the driver housing much like a wind vane while the Oklahoma City units lack this feature. Since Oklahoma City has, so far, not used the voice capability, I am unable to determine if the rotating sirens are voice capable or not. It seems like a waste to put the sophisticated rotator and rotator electronics on a tone only siren, especially when there are around one hundred or so in the system.

I would be curious what some of you who are familiar with Whelen think which model they actually are.

Whelens oscillating sirens stop in the same general direction that they started from. It is completely normal on all vortex units for them to appear to never go off. Sometimes they will stop in other directions but most of the time they will start and stop facing the same way.

Anyone, feel free to correct me if I am wrong with any of this information.

If I'm not mistaken, any Whelen directional siren can be programed to always stop at a "home" position. You can also tell whether or not it is a Vortex or 400X by looking at the rotational area of the siren. On both models there is a box type thing sticking out of one of the sides. If this box is rectangular it is the Vortex series (see picture of Vortex below), and if the box is circular it is the 400X series (see pictures of the 400X below). I've also heard, but not confirmed for sure, that if the siren is voice capable (28,900 and 400X series) there will be an extra box along with the battery's and controls while sirens that aren't voice capable (OA-X, Vortex and Hornet) do not have this extra box (see comparison pictures below) I also believe that the Whelens with fins and all Vortex's. Hope this helps!

Vortex Rotator Box
Picture 1
Picture 2

400X Rotator Box
Picture 1
Picture 2

Voice capable siren boxes
Picture 1

Non Voice capable Siren
Picture 1

Street View or an OKC Vortex (compare this to the two box pics and rotational area pics to see what it is.)
Google Maps Street View Click Here

Thank you for the explanation, it certainly makes sense.

I figured that the installer wouldn't claim that the directional sirens were tone only and then turn around and install voice models.

The Midwest City Vortexes very obviously point all over the place. The Oklahoma City Vortexes, on the other hand, definitely are "homing" I've seen them stop off kilter after a silent test and then return to a precise resting position which is due South for instance. This difference in operation as well as in appearance between the Oklahoma City sirens and those in Midwest City caused the confusion.

I believe Midwest City has the older Vortexes with the fin. I may be wrong, though, I saw it on the Siren Archive. The Vortex near my grandma's house (SW 29th and Eagle Lane) is either always pointing North or West.

coppercarl wrote:Anyone, feel free to correct me if I am wrong with any of this information.

If I'm not mistaken, any Whelen directional siren can be programed to always stop at a "home" position. You can also tell whether or not it is a Vortex or 400X by looking at the rotational area of the siren. On both models there is a box type thing sticking out of one of the sides. If this box is rectangular it is the Vortex series (see picture of Vortex below), and if the box is circular it is the 400X series (see pictures of the 400X below). I've also heard, but not confirmed for sure, that if the siren is voice capable (28,900 and 400X series) there will be an extra box along with the battery's and controls while sirens that aren't voice capable (OA-X, Vortex and Hornet) do not have this extra box (see comparison pictures below) I also believe that the Whelens with fins and all Vortex's. Hope this helps!

Vortex Rotator Box
Picture 1
Picture 2

400X Rotator Box
Picture 1
Picture 2

Voice capable siren boxes
Picture 1

Non Voice capable Siren
Picture 1

Street View or an OKC Vortex (compare this to the two box pics and rotational area pics to see what it is.)
Google Maps Street View Click Here

I have a question I have meaning to ask about the OKC sirens. If you notice on the side of most of the poles towards the top there is a something that looks like a shelf sticking out with 2 white little antennas sticking out of the top of it..what is that used for? I know its not the antenna for activation because there is a normal antenna on the other side of it, and only some siren sites have it. This is the only system that I have seen these.

Alasiren1977 wrote:

coppercarl wrote:Anyone, feel free to correct me if I am wrong with any of this information.

If I'm not mistaken, any Whelen directional siren can be programed to always stop at a "home" position. You can also tell whether or not it is a Vortex or 400X by looking at the rotational area of the siren. On both models there is a box type thing sticking out of one of the sides. If this box is rectangular it is the Vortex series (see picture of Vortex below), and if the box is circular it is the 400X series (see pictures of the 400X below). I've also heard, but not confirmed for sure, that if the siren is voice capable (28,900 and 400X series) there will be an extra box along with the battery's and controls while sirens that aren't voice capable (OA-X, Vortex and Hornet) do not have this extra box (see comparison pictures below) I also believe that the Whelens with fins and all Vortex's. Hope this helps!

Vortex Rotator Box
Picture 1
Picture 2

400X Rotator Box
Picture 1
Picture 2

Voice capable siren boxes
Picture 1

Non Voice capable Siren
Picture 1

Street View or an OKC Vortex (compare this to the two box pics and rotational area pics to see what it is.)
Google Maps Street View Click Here

I have a question I have meaning to ask about the OKC sirens. If you notice on the side of most of the poles towards the top there is a something that looks like a shelf sticking out with 2 white little antennas sticking out of the top of it..what is that used for? I know its not the antenna for activation because there is a normal antenna on the other side of it, and only some siren sites have it. This is the only system that I have seen these.

That's one thing that I have no idea about. Do you happen to know Dillon?

Alasiren1977 wrote:I have a question I have meaning to ask about the OKC sirens. If you notice on the side of most of the poles towards the top there is a something that looks like a shelf sticking out with 2 white little antennas sticking out of the top of it..what is that used for? I know its not the antenna for activation because there is a normal antenna on the other side of it, and only some siren sites have it. This is the only system that I have seen these.

I can return the favor and help you out with that one.

The antenna systems are, for lack of a better term "repeater stations" for Oklahoma City's public safety WIFI system. Many of the streetlight arms have a small box with two antennas sticking up from it that serves the same purpose.

http://www.tropos.com/pdf/whitepapers/OKC_Apr08.pdf

dilloncarpenter wrote:I believe Midwest City has the older Vortexes with the fin. I may be wrong, though, I saw it on the Siren Archive. The Vortex near my grandma's house (SW 29th and Eagle Lane) is either always pointing North or West.

All eight of Midwest City's Vortexes have the fin.

I read that you are returning to live in the metro. If you're into the unusual, Del City has an Eclipse 8. They test Wednesdays at noon.

http://maps.google.com/maps?f=q&source= ... 7,,2,-7.98

Thanks for that info! I will definitely get out there to record it this summer. I am moving to Mustang in about a week and a half, maybe we could get together for a recording sometime.