big sirens for big bridges

[loudmouth]

take a look at this one and tell me what you think

http://www.youtube.com/watch?v=cBCgR3HEGWI

[AllSafe]

They need an STL-10 for the drawbridge?

[Thunderbolt 612]

I think the siren warns people to stay off the bridge as it is being raised, and the siren might be an ATI with the STL recording.

[500AT]

the siren might be an ATI with the STL recording.

How lame is that! I'll take a real STL-10 anyday!

[Whelen Rules]

I think the siren warns people to stay off the bridge as it is being raised, and the siren might be an ATI with the STL recording.

Its a real STL-10 because the ATI's with the recorded sound have to shut off soon because the speakers can not handle a long winddown at that low of a frequency. The ATI's in San Fransico can't be considered sirens (even by electronic standards) at all because they have a prerecorded sound on it, however other electronic sirens produce the sound through tone generators (similar to a mechanical siren just by oscillating and electronic means) instead of having a "recorded siren tone" on them. I wouldn't call an ATI a siren at all period, but I don't want to hijack this thread so I'll stop.

[JasonC]

The US HWY 158 drawbridge in Elizabeth City, NC has two model A sirens on top of the "pilot house" (I guess that's what you would call it?). Several times throughout the years while running outdoor activities for the local college about 1/3 mile away across the river, I got to listen as the A's were sounded for 2 cycles (manually controlled) every time the bridge was raised, which was probably 20 times on a summer day. Not all drawbridges have sirens, but almost all of the ones with pedestrian or slow-speed traffic have them. I've even seen a Q used as one, though I don't remember where.

[loudmouth]

most every bridge up my way has sirens but mostly As,