VOLUME XXIII JULY, 1944 NUMBER 3 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Efifect of Telegraph Distortion on the Margins of Opera- 

 tion of Start-Stop Receivers . . , . W. T, Rea 207 



The Mounting and Fabrication of Plated Quartz Crystal 

 Units R. M. C. Greenidge 234 



Effects of Manufactiu*ing Deviations on Crystal Units for 

 Filters A. R, D'heedene 260 



Mathematical Analysis of Random Noise . . S. O. Rice 282 



Abstracts of Technical Articles by Bell System Authors 333 

 Contributors to this Issue 336 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



NEW YORK 



50c per copy $1.50 per Year 



