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Talk:Write precompensation

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Content moved from hard disk as per discussion on talk:hard disk. - Zephyris Talk 11:09, 18 February 2007 (UTC)[reply]

Is this even accurate?

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I'm not a doctor, but I thought precomp had to do with moving the position of the flux transitions on inner tracks, not changing the intensity, which I could have sworn was actually reduced on inner tracks (not increased as this stub says) -- the TG43 (track greater than 43) line is called RWC (reduced write current) in some FDC data sheets. My vague understanding was that precomp was done because if you use the same bit rate on the shorter tracks, it means the flux reversals end up closer together, which means they have a greater effect on neighboring flux reversals (compared to outer tracks where they're farther apart) and tend to deflect the magnetic fields enough to cause problems with reading. So my hazy vague impression was that write precomp means carefully doing things slightly early/late while writing so that the resulting flux lines are what the read circuitry expects, as if there had been no deflection. Right??? Or something. I can find nothing useful on the net (everyone thinks of precomp as just being a semi-meaningless BIOS parameter on older PCs) and was hoping Wikipedia could illuminate me on the actual nuts and bolts (I'm writing a SW data separator). Thanks! — Preceding unsigned comment added by 24.34.177.232 (talk) 19:09, 26 April 2012 (UTC)[reply]

You're completely right. I just fixed the article to say as much, and a bit more. -- 92.231.117.183 (talk) 00:37, 21 October 2012 (UTC)[reply]

typical timings ?

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I think it would be useful to illustrate which are the typical time intervals involved in precomp. It could help to convey the order of magnitude of these timing adjustments, in comparison to the time it takes to spin the disc once, read a sector, or even detect a single-bit pattern. — Preceding unsigned comment added by Felipe.sanches (talkcontribs) 18:17, 21 October 2017 (UTC)[reply]

More citations.

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Title is self-explanatory, this page needs more citations... Or citations at all for that matter. 2001:1970:5DE6:A300:2595:A47C:CB96:5AE3 (talk) 22:44, 15 December 2022 (UTC)[reply]