

,;•:•: .*'BEbLl SAS'1J^M\ 7UCUNICA 



L JOURNAL 



Some Applications /if S.l>i^ Type " J " Carrier System — ■ 



*•.•*•'•''. L. C. Starhird and J. D. Mathis 338 



Line Problems in the Development of the Twelve-Channel Open- 

 Wire Carrier System — 



L. M. Ilgenfritz, R. N. Hunter and A. L. Whitman 363 



July, 1939 



Frequency-Modulation : Theory of the Feedback Receiving Circuit 



— John R. Carson 395 

 The Application of Negative Feedback to Frequency-Modulation 



Systems—/. G. Chaffee 404 



Survey of Magnetic Materials and Applications in the Telephone 



System— F. E. Legg 438 



Impedance Properties of Electron Streams — Liss C. Peterson .... 465 

 Plastic Materials in Telephone Use — 



/. R. Towns end and W. J. Clarke 482 

 The Dielectric Properties of Insulating Materials — 



E. J. Murphy and S. 0. Morgan 502 



October, 1939 



Experience in Applying Carrier Telephone Systems to Toll Cables 



— W. B. Bedell, G. B. Ransom and W. A. Stevens 547 

 The Toronto-Barrie Toll Cable — M. J. Aykroyd and D. G. Geiger . 588 

 The Computation of the Composite Noise Resulting from Random 



Variable Sources — E. Dietze and W. D. Goodale, Jr 605 



Load Rating Theory for Multi-Channel Amplifiers — 



B. D. Holbrook and J. T. Dixon 624 

 The Quantum Physics of Solids, I — The Energies of Electrons in 



Crystals — W. Shockley 645 



Dial Clutch of the Spring Type — C. F. Wiebusch 724 



