On Apr 7, 2007, at 8:42 AM, Steven N. Hirsch wrote:
   John Kourafas
wrote:
  Also looking for a Micropolis 1325 MFM Drive,
71/80MB , I've seen
 both the ST506 and Mic. 1325 on eBay for like 600.00 which I
 think is crazy... 
 What's the largest capacity 3.5" MFM HDD available? 
 I have an extensive collection of MFM/RLL drives and have _never_
 run across one with that interface in a 3.5" form-factor.  Not sure
 that anything of this sort existed.  5.25" 1/2-ht. was about as
 sophisticated as they got. 
 
   No, they definitely exist, I've installed a great many of them
into machines years ago.  The company I worked for sold a lot of
PeeCees (my karma just hasn't been the same) and we used a HardCard
knock-off extensively; it was a 3.5" MFM drive bolted to a frame
attached to an MFM controller.  I *think* the drive was made by
Miniscribe but I am not sure about that.  It was a 20MB drive.
  The largest MFM drive ever made was _probably_ the
Maxtor 2190 at
 190MB unformatted.  ISTR that there was a logical limit to the
 number of cylinders due to the control protocol (or perhaps
 limitations in the PC BIOSes of the time) and physical limits to
 the number of sectors/cylinder and the number of platters (the 2190
 had 15 or 17?) 
   I believe this is correct.
          -Dave
--
Dave McGuire
Port Charlotte, FL