On 05/05/2017 01:14 PM, Fred Cisin via cctalk wrote:
Although, when I have an "unknown" disk,
before I launch a sector
editor, I type "DIR", just in case it ISN'T anything challenging. I
didn't try flux-transition until I failed with my sector editor.
The hardest that I've run into so far is verifying that a floppy has
*nothing* on it. Flux transition sampling showed zero correlation of
timings (i.e. SD almost 0.0). You could use magnetic developer and see
the tracks, but a photomicrograph showed no distinct reversal
boundaries. Probably DC-erased was my best guess.
--Chuck