In Fig. P4.13 the CB stage Q1 is used as a voltageto-current (V-I) converter. The function of Q2 is to bias Q1 so as to ensure 0-V dc at Q1’s emitter, thus avoiding the need for any ac-coupling...

In Fig. P4.13 the CB stage Q1 is used as a voltageto-current (V-I) converter. The function of Q2 is to bias Q1 so as to ensure 0-V dc at Q1’s emitter, thus avoiding the need for any ac-coupling capacitor. (a) Find Ri , Ro, and the transconductance gain ioyvi if F 5 250 and VA 5 75 V.

(b) Find the signal-to-load voltage gain voyvi if the load is a resistance R2 5 5.0 kV.

(c) Justify the claim that the voltage gain of part (b) could have been estimated as voyvi . R2yR1. Under what conditions is this claim valid?