Resistor networks are sometimes used as volume-control circuits. In this application, they...

Resistor networks are sometimes used as volume-control circuits. In this application, they are referred to as resistance attenuators or pads. A typical fixed-attenuator pad is shown in Fig. 1. In designing an attenuation pad, the circuit designer will select the values of R1 and R2 so that the ratio of vo/vi and the resistance seen by the input voltage source Rab both have a specified value.

a) Show that if Rab = RL, then

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b) Select the values of R1 and R2 so that Rab = RL = 600 Ω and vo/vi = 0.6.

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c) Choose values from Appendix H that are closest to R1 and R2 from part (b). Calculate the percent error in the resulting values for Rab and vo/vi if these new resistor values are used.

Figure 1