3 Nov
2007
3 Nov
'07
8:43 a.m.
On Fri, 2 Nov 2007, Chuck Guzis wrote:
In the early days of the PC AT, many PC XT wanted the
ability to
handle the "new" 1.2MB media. This would have meant replacing the
floppy controller for one that could do the tri-rate (250/300/500
Kbps) trick, but such beasts were expensive (I have a Sysgen
Omnibridge that I use in my XT and it wasn't cheap). Someone (Fred
might remember; my mind is too fuzzy right now) came out with a 1.2MB
drive that would spin down to 180 RPM for high density and 300 RPM
for double-density use. Pretty slick--no need to replace your FDC,
but you get about one-quarter of the read head output voltage at the
lower speed, so performance on the inner tracks wasn't wonderful.
Weltec
I heard (unconfirmed) that the speed at 180RPM wasn't always close enough