VOLUME xm JULY, 1934 



NUMBER 3 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTinC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



The Compandor — An Aid Against Static in Radio 



Telephony— i?. C. Mathes and S. B. Wright . .315 



The Effect of Background Noise in Shared Channel 

 Broadcasting — C. B. Aiken 333 



Wide-Band Open- Wire Program System — 



H. S. Hamilton 351 



Line Filter for Program System — A. W. Clement , , 382 



Contemporary Advances in Physics, XXVIII — The 



Nucleus, Third Part— ^arZ K. Darrow . . . .391 



Electrical Wave Filters Employing Quartz Crystals as 



Elements— VT. P. Mason 405 



Some Improvements in Quartz Crystal Circuit Elements 



—F. R. Lack, G. W. Willard and I. E. Fair 453 



A Theory of Scanning and Its Relation to the Charac- 

 teristics of the Transmitted Signal in Telepho- 

 tography and Television — 



Pierre Mertz and Frank Gray 464 



Abstracts of Technical Papers 516 



Contributors to this Issue 520 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



NEW YORK 



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