482 THE BELL SYSTEM TECHNICAL JOURNAL, APRIL 1951 



Abstract — ^This paper discusses the economic background of the AMA sys- 

 tem, explains its fundamental coding technique, describes its unique appara- 

 tus elements, and presents the basic features of both the recording and 

 processing machinery. 



Conduction Phenomena in Gases * J. P. Molnar.^ Elec. Engg., v. 69, pp. 

 1071-1076, Dec, 1950. 



Abstract — ^A review is made of the processes involved in the breakdown 

 of a gas, in which a body of neutral gas particles that acts as an insulator is 

 changed to one containing a great many charged particles that acts as a 

 conductor. Factors which must be taken into account in discussing these 

 mechanisms include the gas pressure and the nature of the applied field. 



Rooter for Video Signals.* B. M. Oliver.^ I.R.E., Proc, v. 38, pp. 1301- 

 1305, Nov., 1950. 



Abstract — This paper describes a device which takes the nth root of the 

 instantaneous amplitude of a video signal. Its function is to linearize the 

 over-all transfer characteristic, and thus to improve the picture quality in a 

 television system using linear camera tubes and conventional cathode-ray 

 viewing tubes. 



Tone Rendition in Television* B. M. Oliver.^ I.R.E., Proc, v. 3S, pp. 

 1288-1300, Nov., 1950. 



Abstract — This paper is a review of some of the brightness transfer char- 

 acteristics which may be obtained in television using present-day apparatus 

 and techniques. Several families of curves are presented which show the 

 effects of varying one or more of the relevant factors, the remainder being 

 held constant at reasonable values. 



New Electronic Telegraph Regenerative Receiver* B. Ostendorf, Jr.^ 

 A.LE.E., Trans., v. 69, pt. 1, pp. 32-36, 1950. 



Abstract — An all-electronic device for removing distortion from start-stop 

 teletypewriter signals is described. The circuit utilizes a sine wave oscillator 

 for timing and binary counters for synchronization. It provides low output 

 distortion, high tolerance to input distortion, hit-reduction, transmission 

 of steady-space break signals, and regeneration of one element-length of stop 

 time. It features quick change of speed and code, use of office battery power, 

 and reduction of routine maintenance to one adjustment. Over a year's 

 experience has been obtained with about 100 of these units. 



Toward the Specification of Speech.* R. K. Potter^ and J. C. Steinberg.^ 

 References. Acoustical Soc. Am., Jl., v. 22, pp. 807-820, Nov., 1950. 



Abstract — This is an interim report on studies of the specification of speech 



* A reprint of this article may be obtained on request to the editor of the B. S. T. J. 

 iB.T.L. 



