Since I was off from work this morning, I decided to head on down to Jefferson County to record their monthly test, going after one of the remaining two (or three) Thunderbolts in the county. This siren is located just outside of Birmingham, a bit NW of the downtown (near the I-22/I-65 interchange), in a tiny little (probably unincorporated) community literally called "North Smithfield Manor Greenleaf Heights" (try saying that five times fast!), standing next to the fire department in the town. I believe this siren is the only dual-tone Thunderbolt left in the county, and, outside of a possibly reverse-wired blower, still sounds rather healthy.
Jefferson County, AL tests on the first Wednesday of every month at 10 AM, weather permitting.