MM0704, Lesson 2
Transmission Characteristics. By
using resonant circuits, it is
possible to
achieve combinations of
the outputs
previously discussed (figure 2-12). The single, cutoff frequency of the low-pass and high-pass filters overlap and
provide the designer with two cutoff frequencies. The pass band between f1 and f2 can be varied to a very narrow
Figure 2-12. Transmission Characteristics of Band-Pass Filters.
Band-Rejection Filters
Band-rejection filters may be used to remove a specific band of objectionable frequencies, such as static interference,
from a transmitter that is interfering with television reception.
L-section. The parallel-tuned circuit (L1-C1) and the series-tuned circuit (L2-C2) are tuned to the band frequencies to
be rejected (figure 2-13). The
Figure 2-13. L-Section Band-Rejection Filter
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