One diode section of a 6AX5 twin diode is used in a half-wave reactifier like that shown in Fig. 3-23. The supply voltage is e8 = 120 sin 3772 volts, and the circuit resistances are R8 — 0 and Rl — 200 ohms.

a. Plot the diode characteristic on a suitable sheet of graph paper (Fig. 3-25). Determine graphically the value of ib for various values of and plot one full cycle of the waveform of %.

b. Replace the tube by a piecewise-linear model consisting of a 400-ohm resistor in series with an ideal diode. Plot one cycle of ib for this model on the same coordinates as those used for the waveform of part a.

c. Would a different value of series resistance in the model give closer agreement between the results of parts a and 6 ? If so, what value of n would you recommend?

Fig. 3-23

Fig. 3.25