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BELL SYSTEM TECHNICAL JOURNAL 



In Fig. 7 the power spectrum is shown by plotting Wn in db above or 

 below Wq as a function of npdRi for several values of k. These 

 curves illustrate the degree of uniformity obtainable in harmonic am- 



$ -6 



02 0.4 0.6 



1.0 1.2 1.4 



npC2R2 



1.8 2.0 2.2 



Fig. 7 — Harmonic power spectrum plotted from eq. (2) as function of npdRi with k 



as parameter. 



plitudes under different conditions. It may be shown from (3) that 

 Wn has a maximum with respect to n when k is greater than \, if 



1 



npC^Ri = T V^ — I, 

 and that its value at this point is 



A number of relations may be derived from these equations which 

 are useful for design purposes. Thus the form of harmonic distribution 

 is fixed by k and pCiRt- The output power for a given magnetic ma- 

 terial worked at a given fundamental magnetizing force then depends 

 solely upon the volume of core material. Finally, the impedance is fixed 

 by the number of turns per unit length of core. If the impedances 

 desired for primary and secondary circuits differ, separate windings 

 may be used for each circuit. 



