VOLUME XVI OCTOBER, 1937 number 4 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Resistance Compensated Band-Pass Crystal Filters for Use in 



Unbalanced Circuits — W. P. Mason 423 



Magnetic Generation of a Group of Harmonics 



—E. Peterson, J. M. Manley and L. R. Wrathall 437 



The Vodas— S. B. Wright 456 



Radio Telephone Noise Reduction by Voice Control at Receiver 



— C. C. Taylor 475 

 Transmitted Frequency Range for Circuits in Broad-Band Sys- 

 tems— /f. A. Affel 487 



The Dielectric Properties of Insulating Materials 



— £. J. Murphy and S. O. Morgan 493 

 Variable Frequency Electric Circuit Theory with Application to 

 the Theory of Frequency-Modulation 



— John R. Carson and Thornton C. Fry 513 



Irregularities in Broad-Band Wire Transmission Circuits 



•^Pierre Mertz and K. W. Pfleger 541 

 Technical Digests — 



Transoceanic Radio Telephone Development — Ralph Bown . . . 560 

 A Negative -Grid Triode Oscillator and Amplifier for Ultra -High 

 Frequencies— il. L. Samuel 568 



Addendum — 



Radio Propagation Over Plane Earth— Field Strength Curves 



—Charles R. Burrows 574 



Abstracts of Technical Papers 578 



Contributors to this Issue 581 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



NEW YORK 



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