474 



BELL SYSTEM TECHNICAL JOURNAL 



as outputs the sum and the difference of two input voltages*, is shown on 

 Fig. 1. Matching stubs at the crossing, as indicated, are required to re- 

 duce standing waves to a reasonable value. The corresponding type of 

 hybrid ring for providing sum and difference outputs is likewise shown, to- 



OUTPUT E1-E2 



INPUT E2 



OUTPUT E, + E2 



HYBRID JUNCTION 



INPUT E 



NPUT E2 SECTION VIEW 



OUTPUT E1+E2 HYBRID CIRCLE OR RING 



Fig. 1 — Hybrid junction and hybrid circle or ring. 



gether with a diagram dimensioned in terms of wavelength. Since the path 

 lengths from each input to the output between them are equal, this output 

 gives their sum; the path lengths to the remaining outputs differ by one half 

 wavelength, consequently this output feeds out the difference of the two in- 



* More exactly, of two ini)ul jx)wers. 



