Abstracts of Bell System Technical Papers* 

 Not Published in this Journal 



Principles and Applications of Converters for High-Frequency Measure- 

 ments. D. A. Alsberqi. I.R.E., Proc, 40, pp. 1195-1203, Oct., 1952. 

 (Monograph 2030). 



The heterodyne method permits measurements over wide frequency bands 

 with the standards operating at a fixed frequency. The accuracy of such measure- 

 ments depends upon the performance of heterodyne conversion transducers or 

 converters. Design principles are derived to maximize hnearity and dynamic 

 range and minimize zero corrections. These principles have been applied to point- 

 to-point and sweep measurements of delay, phase, transmission, and impedance. 



Ferroelectric Storage Elements for Digital Computers and Switching Sys- 

 tems. J. R. Anderson^. Elec. Engg., 71, pp. 916-922, Oct., 1952. (Mono- 

 graph 2014). 



These ferroelectric storage devices, although still comparatively new, show 

 great promise. They can store up to 2,500 bits of information per square inch in 

 a surface only a few thousandths of an inch thick with pulses less than a micro- 

 second long. 



Transistors in Switching Circuits. A. E. Anderson^ I.R.E., Proc.^ 40, 

 pp. 1541-1558, Nov., 1952. Corrections to Figs. 17, 18 and 19 giving 

 synopses published in December issue, pp. 1732 and 1733. 



The general transistor properties of small size and weight, low power and 

 voltage, and potential long hfe suggest extensive apphcation of transistors to 

 pulse- or switching-type systems of computer or computer-like nature. 



It is possible to devise simple regenerative circuits which perform the normally 

 employed functions of waveform generation, level restoration, delay, storage 

 (registry or memory), and counting. The discussion is hmited to point-contact 

 type transistors in which the alpha or current gain is in excess of unity and to a 

 particular feedback configuration. 



Such circuits, which are of the so-called trigger type, are postulated to involve 

 negative resistance. On this basis an analysis, which approximates the negative- 

 resistance characteristic by three intersecting broken lines, is developed. Con- 



* Certain of these papers are available as Bell System Monographs and may 

 be obtained on reauest to the Publication Department, Bell Telephone Labora- 

 tories, Inc., 463 West Street, New York 14, N. Y. For papers available in this 

 form, the monograph number is given in parentheses following the date of pub- 

 lication, and this number should be given in all requests. 



* Bell Telephone Laboratories. 



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