DETERMINATION OF WAVE FORM 001 



Fischer-Hinnen Method of Analysis. "-A convenient method 

 of harmonic analysis and one in which the arithmetical work 

 is reduced to a minimum is due to Fischer-Hinnen; the procedure 

 is based on two mathematical laws which are demonstrated 

 below. 



Suppose a wave has been plotted and the length ab (Fig. 414), 

 is that of a complete cycle, or 360 of the fundamental. Then 

 between a and b there will be: 



1 complete period of the fundamental 

 3 complete periods of the third harmonic 

 5 complete periods of the fifth harmonic. 



Denote by k the number of complete periods of any harmonic 

 comprised between a and b. Then 



k = 1 for the fundamental 

 k = 3 for the third harmonic 

 k = 5 for the fifth harmonic. 



The equation of the sine curve corresponding to any particular 

 harmonic will be 



Y = A k sin k(0 + a) 



where both 9 and a are expressed in degrees of the fundamental. 

 Now let ab, which corresponds to a whole wave, be divided into 

 P equal parts and P ordinates erected, the first being coincident 

 with a. In Fig. 414 



k = 3, and P = 7. 



860 of Fundamental 



414. Pertaining to Fischer-Hinnen method of harmonic analysis. 

 k = 3, P = 7 



Denote the various ordinates thus [Y P ]i, [Yp]z . . . ; the sub- 

 script, P, within the bracket shows the number of sections into 

 which the base ab is divided, while the subscript outside the 



