.. 5.3

Sound beats
===========

**Objective**

Study the interference of sound from two individual sources. Two Piezo
buzzers are powered by two different sources, and the sound is directed
towards the microphone.

.. image:: schematics/sound-beats.svg
	   :width: 300px

**Procedure**

-  Set WG to 3500 Hz and SQ1 to 3600 Hz
-  Enable WG and SQ1 separately to check the MIC output
-  Adjust positions of Piezo buzzers, from the mic, to get almost same
   amplitude with both
-  Select both of them to get the beat pattern
-  Press FFT to view the frequency spectrum

**Discussion**

From figure it can be seen how the low frequency envelope is created.
Distance between two minimum pressure points., of the envelope,
corresponds to the beat wavelength. The Fourier transform of the output
is shown in figure .
