

1414 THE BELL SYSTEM TECHNICAL JOURNAL, NOVEMBER 195G 

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Fig. 7 — Gain of noninverting modulator, q/Gq = 0.3. 



computed using values of y which make qIG^ = 0.3 at midband. They 

 are thus near the largest gains obtainable for a given value of x. The 

 matching susceptances were assumed to be a single inductance or capaci- 

 tance connected across the terminating resistors. Co/Ci was arbitrarily 

 assumed to have a value of 2. The procedure used was to compute y, 

 hi/ Go , ho/ Go and the maximum available gain at midband using (24), 

 (25) and (26); hi/Go and hi/Go were then multiplied by the appropriate 

 frequency ratio to obtain the terminating susceptances at 50 and 90 mc 

 and the gain at these frequencies was then computed using (14). 



Figs. 7 and 8 show that with the simple matching susceptances used, 

 the gain variation across the band increases as the gain increases. For 

 the same midband gain, the variation in the inverting case is somewhat 

 greater than in the noninverting case. The gain is thus limited by the 

 bandwidth requirements . 



When the gain at 50, 70 and 90 mc is calculated using larger values 

 of g/Go it is found that as g/Go increases the gain variation across the 

 band decreases. In the limit the least variation is obtained when y is 



