The Oak Ridge area as a whole had at least 19 of these omnidirectional Alertronics, 52 total. They were basically early forms of the AL-6000 where each speaker is tied to a single 100 watt driver. The later models that are more abundant have 2 drivers per horn, so they only require 12 speakers as opposed to the 24 these had. Surprisingly for how old they were they did have two way capabilities. This neat PDF detailed results of a test conducted in 2000. They took good care of them from the looks of it.
The active Alertronic's are located at the K-25 plant. The plant itself contained 4 of these beasts and an old building mounted Model 7. The 7 and 3 of the 12000's were taken out of service, while 1 remained along with the 15 6000R's that covered the plant's 2 mile EPZ. They still test them on the first Wednesday of the month at around 11:00 AM.
It appears that they never upgraded these to newer Tempest and I-Force sirens because of the facility being defunct. The ones at the city of Oak Ridge and the Y-12 plant were replaced by T-121s and T-135AC/DCs, while the ones at the lab, more than likely 6000Rs, where replaced by what appears 3 T-135s and the lab's own system of I-Forces.
If I'm not mistaken the last standing diffusion building left there is K-27, and it's supposed to come down in the near future. Eventually this area will make way for new industries. The question at this point is what will come of the sirens once the project is completed.
Proud owner of a Model 1.
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