
365
20.5 More Than One Tuned Circuit
Let us now consider what happens when additional tuned circuits are
used. If we can assume that these circuits do not react on one
another, then it is simple. If one circuit reduces signals at a certain
off-tune frequency 3 times (relative to the response at resonance),
and another circuit is somewhat more lightly damped and reduces
them 4 times, then the total relative reduction is 12 times. If a third
circuit gives a further reduction of 3 times, the total is 36. In other
words, an r.f. amplifier incorporating these three tuned circuits
amplifies this certain frequency 36 times less than it amplifies th ...