
CHAPTER 22
Radio-frequency and Intermediate-
frequency Amplification
22.1 Amplification So Far
We have examined methods of audio-frequency amplification at
some length in Chapter 19. Broadly, they consist of amplifying
devices—transistors—connected together by couplings which are
sometimes called aperiodic because they are designed to have no
natural period or resonance but to treat all frequencies alike, at least
those within the audio band. Since then we have assumed the
practicability of amplifiers that respond only to the very limited
band of frequencies included in one sound channel or the much
wider (but, in proportion to the carrier frequency ...