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BELL SYSTEM TECHNICAL JOURNAL 



ling can be reduced so that for unity standing wave ratio the load conduct- 

 ance appearing at the gap is less than that for optimum power. 



Finally, in making measurements the load impedance is usually evaluated 

 at a point several wavelengths away from the resonator. If performance is 

 plotted in terms of impedances so specified, the points on the contours of 



LOAD POWER G2 = 0.3 

 MAX.LOAD POWER G2=0.3 



LOAD POWER G2=0.3 



MAX. LOAD POWER 6^=0 

 I 



^<m^) 



ye 



POWER 



Fig. 37. — A Rieke diagram for a reflex oscillator having a lossy resonator, taking into 

 account the variation of drift angle with frequency pulling. This results in closed power 

 contours. 



Fig. 38 appear rotated about the center. As the line length in wavelengths 

 will be different for different frequencies, ]:)oints on different frequency 

 contours will be rotated by different amounts. This can cause the contoirs 

 to overlap in the region corresponding to the zero admittance region of Fig, 

 38. With very long lines, the contours may overlap over a considerable 

 region. The multiple modes of oscillation which then occur are discussed 

 in somewhat different terms in the following section. 



