Question 1

Design a passive circuit that will create a “split” (+V/-V) power supply from a single voltage source:


Question 2

After experimenting some with this intercom circuit, you will find that there is a point on the volume control below which so little sound is reproduced that it is almost useless, and a point above which there is substantial distortion. Explain how you could place “stops” to limit the volume control range so that the user could not adjust past these points, making the volume control more useful.


Question 3

Suppose a student builds this circuit and notices that it spontaneously breaks into oscillations, whether or not the “microphone” speaker is picking up any sound. Identify some possible causes of oscillation in a circuit like this, as well as possible fixes.


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