“12 Volt 10 Watt Siren Circuit” in various shades with integrated UM3561 (police, ambulance, fire) 10w 12volt power supply and siren circuit The integrated circuit’s supply 3 volts and 5 volts for the 3.3 volt zener regulated by supply... Electronics Projects, 12V 10V Siren Circuit "analog circuits projects, simple circuit projects, " Date 2014/06/21