"Rod Speed" wrote:

Whatever you like to call it. It has nothing to do with head
calibration, it's the zone of the disk under the ramp where the heads approach the disk and establish a stable flying
height.

Wrong. There was no ramp initially, that came later to avoid
stiction which happens due to the very smooth platter and head

No, it was the glue (used to keep the magnetic media on the aluminum
platters), would get sticky when hot, when the heads parked
themselves, the glue would cool down and the heads would become stuck.
Mostly a Seagate problem.

and the heads never ever deliberately contact the platter anymore,
because the heads dont get anywhere hear the platter from the
ramp until the platters are up to rotation speed and so the last
thing you want is a head crash. They certainly dont ever
deliberately 'the head hits the disk in order to find it'.

You should take the cover off a hard drive and watch how the heads
operate, you turn off the HD the heads move very quickly to the inner
sector, where they sit, as the heads need air to float or lift
themselves up - can't remember the effect that causes this - but it
was used on those old 8" floppies (in plastic cases).

The floppies would sag at the outside edge, and this effect would
bring the edges up and the floppy even. (No, not centrifugal force)

I've never seen a ramp, when I take a HD apart it's always the same
the heads are as close to the spindle as they can get, and all the
heads are sitting on the platters.

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