HE BELL SYSTE^ 



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E^OTED TO THE SCIENTIFIC ^^^ AND ENGINEERIN 

 SPECTS OF ELECTRICAL COMMUNICATION 



GLUME XXX OCTOBER 1951 NUMBER 4 PART ] 



The TD-2 Microwave Radio Relay System 



A. A. ROETKEN, K. D. SMITH and R. W. FRIIS 1041 



Deterioration of Organic Polymers 



B. S. BIGGS 1078 



Electron Tubes for a Coaxial System 



G. T. FORD and E. J. WALSH 1103 



Telephone Traffic Time Averages 



JOHN RIORDAN 1129 



Reproduction of Magnetically Recorded Signals 



R. L. WALLACE, JR. 1145 



Flow of Holes and Electrons in Semiconductors 



R. C. PRLM, III 1174 



Instantaneous Compandors on Narrow Band Speech Channels 



J. C. LOZIER 1214 



Evolution of Inductive Loading (Concluded) 



THOMAS SHAW 1221 



Abstracts of Bell System Technical Papers Not PubUshed in This 



Journal 1244 



Contributors to This Issue 1254 



COPYRIGHT 1951 AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



