🚀 go-pugleaf

In article <1256@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) writes:
>
>I don't understand why nobody has built magnetic disks that spin at
>a constant speed, but vary the clocking of data to the disk so that
>all the bits end up the same width on the media.  This means that you
>might get 30,000 bytes per track on the inside and 90,000 on the 
>outside -- but who cares?

This is an interesting idea to consider. One possible challenge is
that of extracting the clock from the bits stored from the media.
Usually the clock is encoded with the data and there is no separate
clock source. The more you constrain the frequency that the clock
might be at, the easier and faster it is to acquire the clock. If you
let it vary over a factor of three, it might be more difficult,
especially with effects like peak shift, wherein flux reversals
written on the disk tend to repel one another. Because of this, the
flux reversals appear displaced from where they were written. It's not
necessarily impossible, just more difficult. Perhaps the clock
separation circuit would then become the limit on seek time instead of
head settling time. Just some speculations on my part.

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