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OTED TO THE SC I E N T I FIC^^^ AND ENGINEERING 

 •ECTS OF ELECTRICAL COMMUNICATION 



UME XXXV NOVEMBER 1956 NUMBER 6 



Ft 



Nobel Prize in Physics Awarded to Transistor Inventors i 



Theory of the Swept Intrinsic Structure w. t. bead, jbT. 1239 



A Medium Power Traveling- Wave Tube for 6,000-Mc Radio Relay 



J. p. LAico, H. L. Mcdowell and c. r. moster 1285 



Helix Waveguide s. p. morgan and j. a. young 1347 



Wafer-Type Millimeter Wave Rectifiers w. m. sharpless 1385 



Frequency Conversion by Means of a Nonlinear Admittance 



C. F. EDWARDS 1403 



Minimization of Boolean Functions e. j. mccluskey, jr. 1417 



Detection of Group Invariance or Total Symmetry of a Boolean 

 Function e. j. mccluskey, jr. 1445 



Bell System Technical Papers Not Published in This Journal 1454 



Recent Bell System Monographs 1461 



Contributors to This Issue 1465 



COPYRIGHT 1956 AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



