Federal Signal Modulator Monday Siren Testing City of Duncan Oklahoma Voice Steady and Custom Wail 

City of Duncan Siren Testing. Federal Modulator 2008 with voice, steady, custom wail, hi low. Sirens included with this system are 2001-130’s and an ASC Banshee. Sirens nearby also being tested include ASC T-121’s about 8 miles away heard after mod.