The geometry of the signals recorded on tape is interesting.
The VHS variants included linear tracks at the top and bottom edges (for audio and control tracks) and the helical scan for video & HiFi audio toward the center.
The Video8/Hi8 on the other hand did not use linear tracks. The helical scam used over 210 degrees of head rotation; 180 for the video, AFM audio, and tracking signals, followed by ~5 degrees for time and data code, and ~31 degrees for PCM audio. The consumer RCTC system was NOT the same encoding system as the time code Sony used with its professional Hi8 gear, so a consumer Hi8 camcorder that can do RCTC might not read the time code on a professional camcorder recording. (Note: As I recall, the original Video8 design developed by Kodak included a linear track but that was not implemented in most gear.)
The neat thing about the consumer RCTC is that it could be added to an already recorded tape, as could PCM sound, enabling nearly frame-accurate editing of Vdeo8/Hi8 taped material.
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