1. Adopting
this approach, we select all the second-stage resistors to be equal to a practically convenient value,
say 10 kΩ. The problem then reduces to designing the first stage to realize a gain adjustable over the
range of 2 to 1000. Implementing 2R1 as the series combination of a fixed resistor R1f and the variable
resistor R1v obtained using the 100-kΩ pot (Fig. 2.21), we can write