VOLUME XXVIII JANUARY, 1949 no. i 



THE BELL SYSTEM *^^5* 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Propagation of TEoi Waves in Curved Wave Guides 



W. J. Albersheim 1 



A New Type of High -Frequency Amplifier 



J. R. Pierce and W. B. Hebenstreit 33 



Experimental Observation of Amplification by Interaction 



Between Two Electron Streams. . . .A. V. Hollenberg 52 



The Synthesis of Two-Terminal Switching Circuits 



Claude E. Shannon 59 



A Method of Measuring Phase at Microwave Frequen- 

 cies Sloan D. Robertson 99 



Reflection from Comers in Rectangular Wave Guides — 



Conformal Transformation. S. O. Rice 104 



A Set of Second-Order Differential Equations Associated 

 with Reflections in Rectangular Wave Guides — Ap- 

 plication to Guide Connected to Horn . . . . S. O. Rice 136 



Abstracts of Technical Articles by Bell System Authors ... 157 



Contributors to this Issue 162 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



NEW YORK 



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