Accession Number : AD0282292

Title :   A METHOD OF MEASURING THE TIME-DEPENDENT IMPEDANCE OF THE LOAD,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS CRUFT LAB

Personal Author(s) : Iizuka,Keigo

Report Date : 20 APR 1962

Pagination or Media Count : 10

Abstract : By processing a sequence of scope pictures of the output from the probe of a standing-wave detector placed successively at a sequence of positions along a slotted coaxial line, the instantaneous values of a non-stationary load impedance terminating a coaxial line may be measured. This method was applied to measure the instantaneous values of the impedance of a fast-response Cadmium Selenide photo-cell which has a rise and decay time of the order of milliseconds. The experiments were performed at 600 mc. The experimental results were satisfactory and a change that took place in a few milliseconds could easily be measured. On the other hand, a change that occurs in a few tenths of a microsecond would be near the present limit of measurement. This technique could be extended to the measurement of the dynamic impedance of a plasma tube during the rise and decay period of the plasma intensity, or to the measurement of dynamic conductivities, or electric and magnetic susceptibilities in general. (Author)

Descriptors :   (*MICROWAVE PROBES), (*IMPEDANCE), (*COAXIAL CABLES), PLASMAS(PHYSICS), PHOTOELECTRIC CELLS

Distribution Statement : APPROVED FOR PUBLIC RELEASE