rHE BELL SYSTEM 



Jechnical journa^ 



mOTEH TO THE SC I E N T I FlC^^r^ AND ENGINEERING 

 JPECTS OF ELECTRICAL C OM M U N IC AT Io4<C/>j, 



EJ 



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C-UME XXXV JULY 1956 NVMi*R4 



The Effect of Surface Treatments on Point-Contact Transistors 



J. H. FORSTER AND L. E. MILLER 767 



The Design of Tetrode Transistor Amplifiers 



J. G. LINVILL AND L. G. SCHIMPF 813 



The Nature of Power Saturation in Traveling Wave Tubes 



C. C. CUTLER 841 



The Field Displacement Isolator s. weisbaum and h. seidel 877 



Transmission Loss Due to Resonance of Loosely-Coupled Modes in a 

 Multi-Mode System a. p. king and e. a. marcatili 899 



Measurement of Atmospheric Attentuation at Millimeter Wave- 

 lengths A. B. CRAWFORD AND D. C, HOGG 907 



A New Interpretation of Information Rate j. l, kelly, jr. 917 



Automatic Testing of Transmission and Operational Functions 

 of Intertoll Trunks 



H. H. FELDER, a. j. PASCARELLA AND H. F. SHOFFSTALL 927 



Intertoll Trunk Net Loss Maintenance Under Operator Distance 

 and Direct Distance Dialing 



H. H. FELDER AND E, N. LITTLE 955 



COPYRIGHT 1954 AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



