1-20
Figure 1-17B.—Feedback uses in amplifiers.
Figure 1-17C.—Feedback uses in amplifiers.
Figure 1-17D.—Feedback uses in amplifiers.
Positive and negative feedback are accomplished in many ways, depending on the reasons requiring
the feedback. A few of the effects and methods of accomplishing feedback are presented next.
Positive Feedback
As you have seen, positive feedback is accomplished by adding part of the output signal in phase
with the input signal. In a common-base transistor amplifier, it is fairly simple to provide positive
feedback. Since the input and output signals are in phase, you need only couple part of the output signal
back to the input. This is shown in figure 1-18.
