Talk:Helical scan

message: This really needs a diagram. — Omegatron 16:07, 21 July 2006 (UTC)
replies: text: You would think it would be easy to find patent images, but navigating their site is a pain.  I've found a few that would be useful, though? — Omegatron 18:48, 21 July 2006 (UTC)
replies: text: OK I draw a very simple diagram. One more thing. Could someone please draw a simple arrow on a copy of this photo to point out the plane of head tilt in azimuth recording. The text-based description is not clear too me. --Kubanczyk 22:29, 3 April 2007 (UTC)
thread_title:  Diagram need 

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thread_title:  External links modified 

message: I am moving the following uncited material here until it can be properly supported with inline citations of reliable, secondary sources, per WP:V, WP:NOR, WP:CS, WP:NOR, WP:IRS, WP:PSTS, et al. This diff shows where it was in the article. Nightscream (talk) 19:08, 3 September 2022 (UTC)
thread_title: Uncited material in need of citations

message: I see the material on "Slant azimuth" has been removed from the article as of "Revision as of 17:18, 27 July 2022". However, references to "slant azimuth" elsewhere on Wikipedia are being redirected here. That, together with the absence of any description of slant azimuth creates the impression that the term is synonymous with helical scan.  However, the two are different techniques that solve different problems.
Not being a regular Wikipedian, I don't know how to fix this except by offering the following explanation:
Helical scan is all about the angle between the head drum and the tape, whereas slant azimuth is about the angle of each head within the drum. Alternate heads are tilted opposite ways relative to the direction of spin, creating a herringbone pattern of alternately tilted magnetic signals on the tape. On playback, each head can only clearly read the signals that are tilted in its matching direction, so the adjacent tracks cannot be read by accident, or cause cross-talk with the intended signal. This allows tracks to be packed closer together than with the older gap-based method of avoiding cross-talk, thereby increasing the recording time for a given length of tape.
I realise the problem with the removed material is the lack of citations, and right now I can't offer any either (I only just noticed the problem! =:o} ). If I turn up any suitable references later I'll come back and report them here.
 - Paul Bristow (contactable as: bristow.paul, over at the place known as virginmedia.com) 92.239.225.237 (talk) 13:49, 12 January 2024 (UTC)
thread_title:  Confusion with "Slant azimuth".