554 BELL SYSTEM TECHNICAL JOURNAL 



13. "High Quality Radio Broadcast Transmission and Reception," Stuart Ballan- 



tine, Proc. I. R. £., May 1934, Vol. 22, No. 5, pp. 564-629. 



14. "Expanding the Music," A. L. M. Sowerby, Wireless World, Aug. 24, 1934, 



Vol. 35, No. 8, pp. 150-2. 



15. "Extending Volume Range," Radio Engg., Nov. 1934, Vol. 14, No. 11, pp. 



7-9, 13. 



16. "Amplitudenabhangige Verstarker," W. Nestel, E. T. Z., 1934, Vol. 55, No. 36, 



pp. 882-4. 



17. "An Automatic Volume Expandor," W. N. Weeden, Electronics, June 1935, 



Vol. 8, No. 6, pp. 184, 5. 



18. "Die Arbeitsweise der selbsttatigen Regelapparaturen," H. Bartels and W. G. 



Ulbricht, E. N. T., 1935, Vol. 12, No. 11, pp. 368-79. 



19. "Practical Volume Expansion," C. M. Sinnett, Electronics, Nov. 1935, Vol. 8, 



No. 11, pp. 428-30, 446. 



20. "Light-bulb Volume Expandor," Electronics, Mar. 1936, Vol. 9, No. 3, p. 9. 



21. "Simplified Volume Expansion," W. N. Weeden, Wireless World, Apr. 24, 1936, 



Vol. 38, No. 17, pp. 407-8. _ 



22. "Practical Volume Compression," L. B. Hallman, Jr., Electronics, June 1936, 



Vol. 9, No. 6, pp. 15-17, 42. 



23. "Notes on Contrast Expansion," Gerald Sayers, Wireless World, Sept. 18, 1936, 



Vol. 39, No. 12, p. 313. 



24. "Contrast Amplification: A New Development," W. N. Weeden, Wireless World, 



Dec. 18, 1936, Vol. 39, No. 25, pp. 636-38. 



25. "Overmodulation Control and Volume Compression with Variable-mu Speech 



Amplifier," W. B. Plummer, Q. S. T., Oct. 1937, Vol. 21, No. 10, pp. 31-33. 



26. "Limiting Amplifiers," John P. Taylor, Communications, Dec. 1937, Vol. 17, 



No. 12, pp. 7-10, 39-40. 



27. "Low Distortion Volume Expansion Using Negative Feedback," B. J. Stevens, 



Wireless Engr., Mar. 1938, Vol. 15, No. 174, pp. 143-9. 



28. "Distortion Limiter for Radio Receivers," M, L. Levy, Electronics, Mar. 1938, 



Vol. 11, No. 3, p. 26. 



29. "Automatic Modulation Control," L. C. Waller, Radio, Mar. 1938, No. 227, 



pp. 21-6, 72, 74. 



30. "An AVE Noise Silencer Unit," McMurdo Silver, Radio News, May 1938, 



Vol. 20, No. 11, pp. 46. 55. 



