Flutter and Time Errors in Magnetic Data Recorders

Abstract

Flutter and time errors are critical factors in all instrumentation recording. They become even more so in many current and future applications, especially in the data recovery and reduction processes of various telemetering systems. This paper presents analytically the relationship between flutter, time base error, and time base error difference (sometimes called jitter), plus the effects of these errors on direct and FM recording. Methods of measuring these quantities are discussed and experimental examples are given. Spectral and probability density analyses and measurements have indicated that these variables are basically random in nature, and as such, they should be specified in terms of a levels, rather than in conventional peak-to-peak figures. Finally, a measurement method for the typical values of interchannel time error is presented, and some trends of correlation among all channels are discussed.