Circuit Jet Aircraft Sound
This is a simple sound
generator to produce jet engine aircraft sounds and it will run on any battery voltage between 3v and 40v.
The second file is the low speed sound with manually changed resistor to increase then decrease the engine speed.
The circuit will sounds : low speed sound of aircraft, high speed sound of aircraft, missile and machine gun. They are activated by connecting pins 12, 13, 14 or 15 to ground respectively.