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This feature is called—not very aptly, for time is not
involved—delayed a.g.c.
Note that the a.g.c. potential divider system in Fig. 22.19 applies a
small forward bias to the detector diode, sufficient to bring the
working point to the sharpest point on its characteristic curve (see
Fig. 9.14) and thereby increase its response to weak signals.
Oddly enough, a.g.c. is possible with transistors by applying
control bias of the opposite polarity to that just indicated. For this
forward a.g.c. (as it is called) to work, there must be a suitable
amount of resistance in the collector circuit. So when a.g.c. bias is
applied and increases the collecto ...