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BELL SYSTEM TECHNICAL JOURNAL 



An auxiliary path contains the reactance tube fed from a 90° phase shift 

 network connected as shown. The direction of frequency deviation is deter- 

 mined by the sign of the 90° phase shift. The amount of the deviation is 



Fig. 10 — Construction of transmission line reactance tube modulated oscillator, 

 (a) Tube side, (b) Line side. 



determined by the transconductance variation of the reactance tube, by 

 the impedance across which the reactance tube is connected and by the 

 loss in the 90° phase shift network. The linearity is a function of all of these 

 factors. In general the frequency deviation may be increased by increasing 



