ABSTRACTS OF TECHNICAL ARTICLES 769 



Measurement of Hole Diffusion in N-Type Germanium. F. S. Goucher^ 

 Letter to the editor. Phys. Rev., v. 81, p. 475, Feb. 1, 1951. 



Theory and Experiment for a Germanium P-N Junction. F. S. Goucher^, 

 G. L. Pearson', M. Sparks^ G. K. Teal', and W. Shockley'. Letter to 

 the editor. References. Phys. Rev., v. 81, pp. 637-638, Feb. 15, 1951. 



Gain of Electromagnetic Horns.* W. C. Jakes, Jr.^ I.R.E., Proc, v. 39, 

 160-162, Feb., 1951. 



Abstract — An experimental investigation of the gain of pyramidal elec- 

 tromagnetic horns is described. For the horns tested it was found that (1) 

 the "edge effects" are less than 0.2 db so that the gain of the horns may be 

 computed to that accuracy from their physical dimensions and Schelkunoff's 

 curves; and (2) for the transmission of power between two horns the ordinary 

 transmission formula is valid, provided that the separation distance between 

 the horns is measured between the proper reference points on the horns, 

 rather than between their apertures. 



A Pulse Method of Determining the Energy Distribution of Secondary Elec- 

 trons from Insulators.* K. G. McKay^ References. Jl. Applied Phys., v. 

 22, pp. 89-94, Jan., 1951. 



Abstract — A novel method is described of determining the energy dis- 

 trubution of emitted secondaries from an insulator. This is based on an 

 analysis of the transient resulting from pulse bombardment. The analysis 

 is simplest when leakage through the target is negligible, but the effect of 

 leakage is also treated. Space charge limitation of the emitted current is 

 assumed to be negligible. 



Some General Properties of Magnetic Amplifiers.* J. M. Manley'. Refer- 

 ences. I.R.E., Proc, V. 39, pp. 242-251, Mar., 1951. 



Abstract — The magnetic amplifier is discussed in general terms as a 

 carrier system in which there is a modulation gain and a small demodulation 

 loss. Relations are given which show how a magnetic modulator may exhibit 

 a gain. 



Some results of calculation and measurement on the type of circuit in 

 which the modulator output consists of the even harmonics of the carrier 

 source for dc signal input are given. It is shown that the ratio of dc gain to 

 response rise time is a constant depending only on the carrier frequency, the 

 losses in the nonlinear core, and its nonlinearity. The conditions for self- 

 oscillation at the carrier even harmonics are also given. 



Influence of Rotatory Inertia and Shear on Flexural Motions of Isotropic, 

 Elastic Plates. R. D. Mindlin^ References. Jl. Applied Mech., v. 18, pp. 

 31-38, Mar., 1951. 



* A reprint of this article may be obtained on request. 

 » B. T. L. 



