DocumentCode :
1184993
Title :
The Relation of the Carrying Car to the Accuracy of Portable Field-Intensity-Measuring Equipment
Author :
Dewitt, John H., Jr. ; Omberg, A.C.
Author_Institution :
Chief Engineer, Station WSM, Nashville, Tennessee
Volume :
27
Issue :
1
fYear :
1939
Firstpage :
1
Lastpage :
4
Abstract :
The distortion of radio-frequency fields in the vicinity of automobiles is shown to be due to a secondary field resulting from eddy currents induced in the metal parts by the primary field. Theory and experiment demonstrate that the error of measurement caused by the presence of a metal-body car is independent of frequency within the broadcast band. It is shown that the distortion of the field changes with the position of the car, being greatest when the car is in line with the direction of the source and least when the length of the car is normal to the direction of the source. One method of equalizing this difference is pointed out. Measured field contours around three types of automobiles are illustrated.
Keywords :
Antenna measurements; Automobiles; Broadcasting; Coils; Distortion measurement; Eddy currents; Frequency measurement; Radio frequency; Time measurement; Voltage;
fLanguage :
English
Journal_Title :
Proceedings of the IRE
Publisher :
ieee
ISSN :
0096-8390
Type :
jour
DOI :
10.1109/JRPROC.1939.228634
Filename :
1686746
Link To Document :
بازگشت