TRANSMISSION LINES FOR RADIO SYSTEMS 



429 



the transmitting case, tuned circuits are often found to be both bulky 

 and costly. There are a number of schemes which employ a short sec- 

 tion of line as a transformer element. These are feasible only at fre- 



FIG 12-A 



</) 6 



Z 5 



LOSS 3 lOLOGio 



ab[i*n2]t n[a'> b'] 



DECIBELS 



WHERE n = -^ OR -^ 

 =0 *^ 



a=COSHo<l b = SINH o<l 



oC = ATTENUATION FACTOR 



Z>,= CHARACTERISTIC IMPEDANCE 



Fig. 12 — Line loss as a function of the degree of matching. The several curves 

 are designated in terms of the minimum line loss obtained for the case of a perfect 

 match with the line characteristic impedance. 



quencies for which the wave-length is short. The circuits so provided 

 are extremely simple and cheap. 



In another paper ^^ a scheme for employing a one-quarter wave- 



16 E. J. Sterba, Proc. I. R. E., p. 1184, July, 1931. 



