A new design of a total difference-frequency distortion (TDFD) meter having the highest sensitivity to date is described. It requires no critical filter stages and produces its own test signals. Quadrature synchronous detectors, simple passive and active filters, and phase-locked-loop synthesizers are used to achieve a measurement dynamic range of 135 dB or 0.15 ppm. The microprocessor displays TDFD and shows odd- and even-order distortion fractions. The possibility exists of locking to an external reference, allowing the measurement of CD players or a change of test signal frequency by shifting the master reference. Block diagrams and example measurements are presented.

Authors: Scott, Jonathan; Heuer, Dirk
Affiliations: Department of Electrical Engineering, University of Sydney, Australia ; Heuer Instruments, Carlingford, Australia(See document for exact affiliation information.)
JAES Volume 42 Issue 6 pp. 483-489; June 1994
Publication Date: June 1, 1994 Import into BibTeX
Permalink: https://www.aes.org/e-lib/browse.cfm?elib=6940

Click to purchase paper as a non-member or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!

This paper costs $33 for non-members and is free for AES members and E-Library subscribers.

Learn more about the AES E-Library

E-Library Location: (CD aes5)   /jrnl8997/1994/8541.pdf

Start a discussion about this paper!