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 a recording. Overall, these sirens are pretty potent at a distance and the T-135 on the other side of the hill makes for a cool ambiance. The coverage is great on this system and it makes for a cool sound on test day, especially with the rain. These sirens are sounded every first Wednesday of the month at noon in alert. If you are in the area, I suggest that you try to record these sirens after catching the ETTP sirens at 11 because it is a really neat system, just make sure that you aren't recording in a restricted area. Here is the video and thanks for watching!
https://www.youtube.com/watch?v=qmE7H3ed_ik