Abstracts of Technical Articles by Bell System Authors 



Remaking Speech} Homer Dudley. Speech has been remade 

 automatically from a buzzer-like tone and a hiss-like noise correspond- 

 ing to the cord-tone and the breath -tone of normal speech. Control 

 of pitch and spectrum obtained from a talker's speech are applied 

 to make the synthetic speech copy the original speech sufficiently 

 for good intelligibility although the currents used in such controls 

 contain only low syllabic frequencies of the order of 10 cycles per 

 second as contrasted with frequencies of 100 to 3000 cycles in the 

 remade speech. The isolation of these speech-defining signals of 

 pitch and spectrum makes it possible to reconstruct the speech to a 

 wide variety of specifications. Striking demonstrations upon altering 

 the pitch of the remade speech stress the contribution of the pitch to 

 the emotional content of speech. Similarly the spectrum is shown 

 to contribute most of the intelligibility to the speech. 



Deviations of Short Radio Waves from the London-New York Great- 

 Circle Path.^ C. B. Feldman. During the past year experiments 

 have been made to determine the frequency of occurrence and extent 

 of deviations of short radio waves from the North Atlantic great-circle 

 path. For this purpose the multiple-unit steerable antenna (Musa), 

 described to the Institute at its 1937 convention, has been used to 

 steer a receiving lobe horizontally. This is accomplished by arraying 

 the unit antennas broadside to the general direction from which the 

 waves are expected to arrive. The Musa combining equipment then 

 provides a reception lobe in the horizontal plane, steerable over a 

 limited range of azimuth. Two such Musas have been used, one of 

 which possesses a wide steering range but is blunt, while the other is 

 sharp but is restricted in range. Transmissions from England have 

 been studied with this equipment at the Holmdel, N. J., radio labora- 

 tory of the Bell Telephone Laboratories. Comparisons of results 

 obtained on transmission from antennas directed toward New York 

 with those from antennas otherwise directed have, to a limited degree, 

 given results representative of the efifects of horizontally steerable 

 transmitting directivity. Observations made on these British trans- 

 missions during the past eight months have disclosed the following 

 characteristics: 



1 Jour. Acous. Soc. Amer., October 1939. 



2 Proc. I. R. E., October 1939. 



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