Post #1581446
2026-04-18 06:30 UTC
@muddle @infosecdj It could be more mondane than that, I think floppy drives always use the same bits/angle. so the VFO would be to track variations in motor speed.
Replies (1)
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@brouhaha@mastodon.social 2026-04-18 08:42
@RueNahcMohr @muddle @infosecdj The vast majority of floppy drives use constant motor speed and constant bit rate, on a given disk, so have higher FCPI near the center. Apple, Commodore, and Sirius were notable exceptions. Apple and Sirius/Victor varied motor speed but kept data rate constant. Commodore kept motor speed constant but varied data rate. Even at constant rotation rate and data rate, high data densities require a PLL, and thus a VCO or digital equivalent, for reliable reading.