PURPOSE: To demonstrate that there exist ultrasonic waves with frequencies above the range of human hearing.
DESCRIPTION: The oscillator drives a supertweeter at frequencies from 500 Hz to over 25 kHz. The microphone signal on the oscilloscope provides evidence that the ultrasonic waves are really there.
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Wave generator, supertweeter, Sony condenser microphone, and oscilloscope.
SETUP TIME: 5 min.
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