3B40.30 - Doppler Effect - Microwave Beats

Set the microwave receiver pointing in the same direction as the transmitter and move just far enough in front of the transmitter to get a faint signal.  As the mirror is moved closer and farther away from the transmitter a beat frequency should be observed that is proportional to the speed of the mirror.
Code Number:
3B40.30
Demo Title:
Doppler Effect - Microwave Beats
Condition:
Excellent
Principle:
Doppler Effect Using Microwaves
Area of Study:
Acoustics
Equipment:
Amplifier, speaker, microwave transmitter and receiver, mirror plate.
Procedure:

Set the microwave receiver pointing in the same direction as the transmitter and move just far enough in front of the transmitter to get a faint signal.  As the mirror is moved closer and farther away from the transmitter a beat frequency should be observed that is proportional to the speed of the mirror.

References:
  • Richard W. Cole, "Demonstration Doppler Radar", TPT, Vol. 10, # 7, Oct. 1972, p. 399.
  • F. Neff Weber, Paul Helminger, and Doelores Lynn Moulds, "Student Microwave Experiments Involving the Doppler Effect", AJP, Vol. 48, #9, Sept. 1980, p. 737.
  • S. C. Bloch, W. E. Abare and G. E. Pidick, "Interference-Fringe Counting as an Aspect of Doppler Shift", AJP, Vol. 35, # 3, March 1967, p. 223.
  • F. D. Manchester, "Simple Doppler-Shift Apparatus Using Microwaves", AJP, Vol. 33, #6, June 1965, p. 499. 


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