PURPOSE: To experimentally determine the frequency of the radiowave transmitter.
DESCRIPTION: The signal from the radiowave transmitter (on small stand at left in photograph) is picked up by the receiving antenna (on scope cart) and displayed on the oscilloscope. From the measured period of the radiowaves on the scope the frequency can be calculated. In the above photo, the period of the radiowaves is slightly greater than 12 nanoseconds, so the frequency is about 80 MHz.
The frequency of the wireless microphone can also be determined this way.
SUGGESTIONS: The transmitter should be located about six feet away from the receiving antenna (on scope cart) to reduce the signal level to a readable amplitude for the scope.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Radiowave transmitter and receiving antenna with oscilloscope.
SETUP TIME: 5 min.
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