4-59. Redraw the filter circuit so that you can see the voltage divider action (see Figure

4-24, view (A). Remember, the 165 volts peak-to-peak 60 Hz provided by the rectifier

consists of both an AC and a DC component. In Figure 4-24, you can see that the capacitor

(C1) offers the least opposition (265 ohms) to the AC component. Therefore, the greatest

amount of AC will flow through C1 (the heavy line indicates the AC current flow through

the capacitor). So, the capacitor bypasses, or shunts, most of the AC around the load.

Figure 4-24, view (B)), you will have a total resistance of 258 ohms. To compute this, use

the following formula:

(R1) (R 2)

RT =

R1 + R 2

You now have a voltage divider (see Figure 4-25). Notice that because of the impedance

ratios, a large amount of ripple voltage is dropped across L1 and a substantially smaller

amount is dropped across C1 and RL. You can further increase the ripple voltage across L1

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