Frequency Response Characterization and Compensation of the Lamdascan™ A/F Analyzer

A procedure which uses modulated engine exhaust to characterize the amplitude vs. frequency response of air-fuel ratio (A/F) measuring equipment is described, and typical results obtained when the procedure is applied to a standard Lamdascan A/F Analyzer are given. A technique for extending the frequency response of the Lamdascan instrument by a factor of approximately two is discussed, and the measured characteristics which result when the improvements are incorporated into the instrument are presented.