MM0704, Lesson 2
there is maximum tank (series resonant) current. Very little line current will flow at this frequency (figure 2-9A). By
contrast, an inductor and a capacitor in series allows maximum current at their resonant frequency (figure 2-9B).
Therefore, careful selection of series and parallel resonant circuits can determine at which frequency current flows to
the load. In the tank circuit (figure 2-9C), L1 and C1 transmit freely between f1 and f2, while the parallel tank affords
an easy path for frequencies below f1 (through L2) to ground, as well as a path for frequencies above f2 (through C2).
Figure 2-9. L-Section, Band-Pass Filter
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