VOLUME xxiii JANUARY, 1944 number i 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



The Discemibility of Changes in Program Band Width 



— D. K. Gannett and Men Kerney 1 



Use of the Etch Technique for Determining Orientation 

 and Twinning in Quartz Crystals 



— G. W. Willard 11 



Modes of Motion in Quartz Crystals, the EfiEects of Coup- 

 ling and Methods of Design . . . R. A. Sykes 52 



Response of a Linear Rectifier to Signal and Noise 



—W. R. Bennett 97 



Dielectric Constants and Power Factors at Centimeter 

 Wave-Lengths Carl R. Englund 114 



Abstracts of Technical Articles by Bell System Authors 130 

 Contributors to this Issue 133 



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