TRANSISTOR CIRCUITS FOR ANALOG AND DIGITAL SYSTEMS 



307 



resulting current transmission. The amplitude of the transmission falls 

 off at a rate of 6 db per octave with the corner frequency C05 determined 

 by C'3 and the low frequency value of the transistor input impedance. 

 The inductance L3 introduces a 12 db per octave rising asymptote with 

 a corner frequency at C03 = WLsCs . The corner frequencies C03 and C05 

 are selected in order to obtain a desirable loop current transmission 

 characteristic (specific transmission characteristics are presented in Sec- 

 tions 3.0 and 4.0). The half power frequency of the current transmission 

 of the transistor, wi , does not. appear directly in the transmission char- 

 acteristic of the circuit because of the variation in the transistor input 

 impedance with frequency. 

 The overall (3 circuit of the feedback amplifier can also be used for 



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FREQUENCY IN CYCLES PER SECOND 



Fig. 7 — Interstage shaping network. 



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