The physicist John Robinson invented the siren in 1799 and originally intended for it to be used as a musical instrument, however since it could efficiently produce a lot of sound it was later used as a basis for warning sirens. These were perforated disks that would rotate in front of each other to...

After getting a successful test at the ETTP Alertronics, I went with 4j25, airplanedude, Josh555, and LeadColliamtor to record the Oak Ridge, TN system of Tempests. We had originally planned on recording a T-135 DC, however after being unable to obtain permission, we went to the closest T-121 to get...

I went up to Oak Ridge for the day with 4j25, airplanedude, Josh555, and LeadColliamtor to record the Oak Ridge, TN warning sirens and despite the rain, we were able to finally catch a successful recording! These sirens are part of the East Tennessee Technology Park siren system and serve the area s...

This looks to be quite similar to a Federal Signal Model AX, simply an omnidirectional explosion proof version of a Model A. It might be a much earlier version of the siren judging by the logo, but the chopper assembly matches up with the modern AX almost identically. The motor end is the only thing...

I found this whilst looking for the Buford Dam water release sirens at Lake Lanier in a Gwinett Times article. The sirens can be heard in the video below along with an image from the article. The sirens sound when water is released from the dam and there are four sirens located between the dam and t...

These new sirens look really intriguing, I wonder how they will compare to some of the other electronics on the market today. Judging by the quality of the other products that Sentry makes, I am sure that these will be reliable and well built though. The one thing that intrigues me is the logo at th...

Three of the thunderbolts are accounted for, with only one still remaining unfortunately. They are: Mary Walker Towers (gone) Belvoir Pharmacy (gone) Bank Building at 7th and Market (Still there) Would you happen to know when the Mary Walker Towers unit removed? I had noticed that it didn’t seem to...

I love the contrast in this photo between the rusty and weathered Clayton Whirlwind against the clear blue sky. Photo taken in Cadwell, GA last summer:

The new year is finally here, and last night I welcomed it by sounding my Federal Signal Model A. Last year I used my Thunderbolt 1000T to ring in the new year, however due to the fact that my weather station was reading 10 F with the wind chill, I decided to just set off the Model A. While it certa...

Whelen has never ventured into the mechanical siren world and as DJ226 said, the Xecutor was their closest attempt. Whelen still does include a mechanical tone on some of their electronic sirens today (my local ambulances use these tones in fact), however it is by no means as realistic as the Xecuto...