I did a 6 PM blast of my Thunderbolt 1000T. The information tag on the side of the rotator box says that the type is a 1000 3 phase, but this siren has a dual tone 5/6 port chopper. The serial number is T-2356-D. I am pretty sure that this has an A series blower, making it a 1000AT.
https://www.youtube.com/watch?v=CfsdN-onkK8