4 Jun
2012
4 Jun
'12
7:15 a.m.
On 06/04/2012 04:54 AM, Christian Corti wrote:
On Sun, 3 Jun 2012, Fred Cisin wrote:
There are two common track density 48 and 96 tpi or otherwise said
40 and 80 cylinders. there are more tracks/cylinders to the radial inch.
Also the head width is narrower by two for the 96tpi.
Recording density is experssed in FRPI Flux Reversals per Inch.
The problem with floppies is that for 5.25 you had:
for 48tpi:
Single sided 40 track FM (about 80k)
Single sided 40 track MFM (about 160K)
Two sided 40 track MFM (about 160k)
Two sided 40 track MFM (about 360k)
for 96tpi:
Single sided 80 track FM (about 180k)
Single sided 80 track MFM (about 360K)
Two sided 80 track MFM (about 360k)
Two sided 80 track MFM (about 720k)
for 96tpi, HD:
Two sided 80 track double data rate MFM (about 1.2M)
The problem is that marketing named them!
so we have single density, double density, quad density
(mostly seen in the cp//m world), and HD never mind the
sector size variations and layout.
I also left out the oddball drives like 35track and 100tpi.
Allison
A DD track is about 1/3mm wide, and spaced about
1/2mm apart (48 tpi)
An HD track is about 1/6mm wide, and spaced about 1/4mm apart (96tpi)
How on earth do you come to that conclusion? I have enough 96tpi "DD"
drives. I think you mix up track density and recording density, two
unrelated things.
Christian