Charts for Simplifying High-Impedance Measurements with the Radio-Frequency Bridge

The equal-arm capacitance bridge for making radio-frequency impedance measurements gives excellent results with very little labor, provided the magnitude of the unknown impedance is not too high. If the unknown is high, and if its components change rapidly with frequency, it is desirable from the st...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the IRE 1943-07, Vol.31 (7), p.372-378
Main Author: Nielsen, R.L.
Format: Article
Language:English
Subjects:
Arm
Bridge circuits
Broadcasting
Capacitance
Electrical resistance measurement
Impedance measurement
Inductance
Interpolation
Measurement standards
Radio frequency
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The equal-arm capacitance bridge for making radio-frequency impedance measurements gives excellent results with very little labor, provided the magnitude of the unknown impedance is not too high. If the unknown is high, and if its components change rapidly with frequency, it is desirable from the standpoint of ease of balance and accuracy of determination to shunt the unknown at the bridge terminals with a high-quality fixed condenser of known capacitance. The difficulty with this so-called shunt-condenser method has been the tedious calculations necessary to convert bridge readings into resistance and reactance of the unknown. In this paper there are presented charts which allow this conversion to be made quickly and easily. This should make possible more extensive use of the shunt-condenser method, especially in the standard broadcast band where there is considerable need for this type of measurement. In an example on the use of the charts there is pointed out a further advantage of the shunt-condenser method, the possibility for interpolation between bridge readings in the case of impedances which change very rapidly with the frequency.
ISSN:0096-8390
2162-6634
DOI:10.1109/JRPROC.1943.231353