RK06 alignment pack

[Noel Chiappa]

    > From: Pontus Pihlgren

    > How was alignment packs produced?

On a special rig, I'm pretty sure. I don't know how the RK06 alignment pack
works, but I am familiar with the RK05 (our machine had them, and we had to
realign one after a head crash), and I assume it's probably similar; it had to
have been created on a special rig (the exact nature of which I don't know,
but I know a normal drive couldn't write it).

For the RK05, the alignment pack has alignment tracks with alternating
sectors written a couple of thousandths of an inch offset from the track's
nominal center line; when one watches the head's output on a 'scope (at a
timebase sufficient to show pairs of sectors), if the output for both sectors
in a pair is at the same amplitude, the head is correctly aligned. If not,
it's easy to see on the 'scope - one has higher output than the other.

	Noel