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BELL SYSTEM TECHNICAL JOURNAL 



Except at the higher inputs, the power output increases continuously 

 with load resistance over the load range considered. This is to be 

 expected, since the highest load resistance of 12,000 ohms is much 



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INPUT IN PEAK VOLTS 

 Fig. 12 — Characteristics of a power pentode. Power output, P, in watts, second 

 and third harmonics in decibels below the fundamental, as functions of the peak input 

 when a sinusoidal voltage is applied to the control grid. 



smaller than the plate resistance of the tube, which is 52,000 ohms. 

 For small inputs, the maximum power output would be obtained, as it 

 is in triodes, when the load resistance is equal to the plate resistance of 



