I wrote about the problems with "modern"
removable-rigid-media drives:
>> Air filters? Ha! They have nothing but a shutter on the cartridge and a
>> door flap on the drive. Absolute rubbish. It's miraculous that they work
>> even for a few weeks.
"Hans Franke" <franke(a)sbs.de> wrote:
> Dame has been said on 8" FD: These will be damaged within hours
Same?
No, no one with a grasp of how the technology works
has ever claimed that a
little dust or smoke will damage a floppy disk or drive. Floppy disks use a
much different head/media interface than winchester rigid-media drives. Dust
or smoke particles can and will cause head crashes on winchester drives.
And dust particles will work like sandpaper and grind the
disk surface (we have a nice wording in German for that:
FD are 'Spanabhebende Datenverarbeitung'. Datenverarbeitung
means data provessing and spanabhebend is the term for a
metal forming process thru producing fillings with using
cutting tools like on a lathe :). Any material will degenerate
the surface - and even in clean room condition, the head
itself grinds the magnetic surface away.
I am not a technical expert on the innards of Iomega
Jaz and Syquest SyJet
and Sparq drives. However, a casual examination suggests that they use
winchester technology. This is consistent with the manufacturers descriptions
of the drives in product literature, and it is also consistent with the
high failure rate I've observed (approaching 100% after four weeks on the
Syquest drives). Winchester drive technology was developed for permanently
sealed HDAs, not cartridge drives. And even the sealed drives were designed
with air filtration.
Maybe to clear some things:
We are not talking about 'Winchester' technology
there are 4 basic technologies for the head/surface
management of disk Magnetic:
1. Fixed head over hard surface
2. Flying head over fixed surface (Winchester)
3. Fixed head over flexible surface (Bernulli)
4. Head grinding over flexible surface (Floppy)
(also tapes go into #4 but since the head surface
speed is only slow, the effekt is less visible)
And we are talking about 2 vs. 4 (head flying over hard
surface vs. head on flexible surface). The other ones
have been used in several drive types thru the past. And
all in encapsulated (seled) and 'free' environment.
Before there where capsulated 'Winchester' type drives
mainframes relied on removable disk stacks wit technology
#1. Of course these had air filtration etc., but the stacks
itself have not been encapsulated at all time, especialy not
air tight.
The old Syquest 44s (and following) are using this technology
(number 1), like back in the 60s to 80s on mainframes. The
head surface distance is basicly fixed by the drive mechanic,
althrough modern drives of this kind have some sort of control
to adjust it.
Someone pointed out that he'd had no trouble with
Syquest 230M drives; I've
personally had reasonable results with their earlier 44M and 88M 5.25 inch
drives. I don't what differences between the lower and higher capacity
drives accounts for the huge difference in reliability.
I have used (and still use) the 44/88 drives over years without
any failiure. the same with the 3 1/2" drives, So I've no reason
to fight - instead I'm very sad that Syquest fades away.
Gruss
hans
--
Ich denke, also bin ich, also gut
HRK