Viktor Pilpenok wrote in a message to All:

 VP> Hello All!

 VP> (Here is some additional info about 5.25" floppies)

 VP> For 5.25" floppies it was less messy than 3.5". The basic formats
 VP> were: 160k - 1 Sides 40 Tracks 8 Sec/Track  180k - 1 Sides 40
 VP> Tracks 9 Sec/Track 320k - 2 Sides 40 Tracks 8 Sec/Track  360k - 2
 VP> Sides 40 Tracks 9 Sec/Track 640k - 2 Sides 80 Tracks 8 Sec/Track 
 VP> 720k - 2 Sides 80 Tracks 9 Sec/Track 1.2m - 2 Sides 80 Tracks 15
 VP> Sec/Track

 VP> The 2 most common formats with more sectors/track were: 11 s/t
 VP> (880k - used on 720k floppies) and 20 s/t (1.6m - used on 1.2
 VP> floppies).

 VP> There were 2 pretty popular formats with additional tracks in the
 VP> 360k days: 41 and 42 tracks (410k and 420k) And 2 less popular used
 VP> on 1.2 floppies - 82 and 83 tracks (1.48m and 1.49m)

And then of course there were all the CP/M formats (on 5.25",  almost
no machines used 3.5"),  and the 96tpi drives and 100tpi drives,  as
were used in the DEC Rainbow and the C= 8050...     :-)

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