Convention Paper
Azimuth and Interchannel Time Displacement Error in Multi-Track Magnetic Tape Recording
AES Convention 66 · Paper 1666 · May 1980
Abstract
Tape is often slit with a sinuous centerline ("country laning"). When this tape travels through a transport, the recording on one track shows a varying time displacement with respect to that on another track. When the same signal is recorded on two tracks, and the reproduced signals are subsequently combined, the time displacement produces a "comb filter" frequency response. The output of a full-track head shows a response which is similar up to the first output null. This filter response is used here as a "slope detector" to measure the short-term time azimuth angle variations. Typical peak to peak azimuth angle variations are 600 microradians (0.03 degrees, or 2 minutes); this sets a limit to the interchannel time-displacement performance of recording systems, and to the accuracy of azimuth angle measurements.
