Hi all

I have an NC200 which works fine except the floppy disk drive which
appears to be unserviceable.

I have stripped the drive and a little hair spring about an inch long
fell out but I can't see where on the drive internals it was supposed to go!

When a disk is loaded and I try to access the drive the stepper motor
drives the heads towards to end of the motor thread and then end stops.

What I really need is a scrap NC200 with a 'known good' drive.

Can anyone help please?

Nick

"Nick" wrote in message
eenews.net...
Hi all

I have an NC200 which works fine except the floppy disk drive which
appears to be unserviceable.

I have stripped the drive and a little hair spring about an inch long fell
out but I can't see where on the drive internals it was supposed to go!

When a disk is loaded and I try to access the drive the stepper motor
drives the heads towards to end of the motor thread and then end stops.

What I really need is a scrap NC200 with a 'known good' drive.

Can anyone help please?

Nick

I'm not familiar with this model, I assume it has a standard 3.5" floppy,
and not an old 5.25"?

If the drive loads/ejects discs properly, and the heads snap shut against
the disc when inserted, my guess is the spring doesn't go anywhere! 9 times
out of ten, when I extract springs from floppy disc drives, the spring
jumped out of a faulty floppy disc and into the drive mechanism. The spring
is usually the one which closes the protective metal slider on the disc
itself.

If I'm right, this could mean that a faulty floppy disc probably fell apart
inside the drive and was forcibly extracted, damaging/misaligning the
drive's read/write heads. Is there no way a standard floppy disc drive can
be fitted? Repairing faulty floppy disc drives is rarely successful.

Dave

Dave D wrote:
"Nick" wrote in message
eenews.net...

Hi all

I have an NC200 which works fine except the floppy disk drive which
appears to be unserviceable.

I have stripped the drive and a little hair spring about an inch long fell
out but I can't see where on the drive internals it was supposed to go!

When a disk is loaded and I try to access the drive the stepper motor
drives the heads towards to end of the motor thread and then end stops.

What I really need is a scrap NC200 with a 'known good' drive.

Can anyone help please?

Nick


I'm not familiar with this model, I assume it has a standard 3.5" floppy,
and not an old 5.25"?

If the drive loads/ejects discs properly, and the heads snap shut against
the disc when inserted, my guess is the spring doesn't go anywhere! 9 times
out of ten, when I extract springs from floppy disc drives, the spring
jumped out of a faulty floppy disc and into the drive mechanism. The spring
is usually the one which closes the protective metal slider on the disc
itself.

If I'm right, this could mean that a faulty floppy disc probably fell apart
inside the drive and was forcibly extracted, damaging/misaligning the
drive's read/write heads. Is there no way a standard floppy disc drive can
be fitted? Repairing faulty floppy disc drives is rarely successful.

Dave


Dave

I agree re the spring; the one that fell out does look suspiciously like
those used to close the shutter on a 3.5" floppy disk.

When I first powered it up I tried to format a 720kB floppy and it went
all the way through to track 80 but then said there had been an error
and the disk had not been formatted. I then tried a 1.44MB (didn't
realise at the time it was a DSDD drive) and had similar results.

The following day I tried it again with the 720kB floppy but the heads
moved all the way to the centre of the disk and the stepper motor
started slipping with a buzzing noise until I popped the disk and the OS
trapped the interrupt.

That's when I removed the drive and the spring fell out.

I cleaned the heads and checked the connectors both external and
internal to the drive, but no go.

I then confirmed from the spec that the NC200 has a 3.5" drive which
formats DSDD DOS compatible i.e. 720kB.

But the interface looks non-standard. It's only got 26 pins vs. 34 pins
on a standard PC FDD. It's a Z80 based machine so I will inspect the
motherboard to see what disk controller it uses. It may then be
possible to interface a PC FDD to it.

The easiest solution would be to find a scrap machine and change the drive.

This machine only cost me 70p so fixing it makes no economic sense, but
I have this irrational desire to restore it to full working order!

Nick

"Nick" bravely wrote to "All" (08 Sep 05 21:31:19)
--- on the heady topic of "Amstrad NC200"

There is a spring that goes on the loading arm of the upper head
assembly. If it fell out then the heads might not be reading properly.
If you feel no tension when trying to lift the upper head that is it.
What did you do to the drive that resulted in the spring falling off?
Those old 5-1/4" drives bring back memories.

A*s*i*m*o*v


Ni From: Nick
Ni Xref: core-easynews sci.electronics.repair:341672

Ni Hi all

Ni I have an NC200 which works fine except the floppy disk drive which
Ni appears to be unserviceable.

Ni I have stripped the drive and a little hair spring about an inch long
Ni fell out but I can't see where on the drive internals it was supposed
Ni to go!
Ni When a disk is loaded and I try to access the drive the stepper motor
Ni drives the heads towards to end of the motor thread and then end
Ni stops.
Ni What I really need is a scrap NC200 with a 'known good' drive.

Ni Can anyone help please?

Ni Nick

.... Back when I was a boy, we carved our own ICs out of wood.

"Nick" wrote in message
eenews.net...
Dave D wrote:
"Nick" wrote in message
eenews.net...

Hi all

I have an NC200 which works fine except the floppy disk drive which
appears to be unserviceable.

I have stripped the drive and a little hair spring about an inch long
fell out but I can't see where on the drive internals it was supposed to
go!

When a disk is loaded and I try to access the drive the stepper motor
drives the heads towards to end of the motor thread and then end stops.

What I really need is a scrap NC200 with a 'known good' drive.

Can anyone help please?

Nick


I'm not familiar with this model, I assume it has a standard 3.5" floppy,
and not an old 5.25"?

If the drive loads/ejects discs properly, and the heads snap shut against
the disc when inserted, my guess is the spring doesn't go anywhere! 9
times out of ten, when I extract springs from floppy disc drives, the
spring jumped out of a faulty floppy disc and into the drive mechanism.
The spring is usually the one which closes the protective metal slider on
the disc itself.

If I'm right, this could mean that a faulty floppy disc probably fell
apart inside the drive and was forcibly extracted, damaging/misaligning
the drive's read/write heads. Is there no way a standard floppy disc
drive can be fitted? Repairing faulty floppy disc drives is rarely
successful.

Dave

Dave

I agree re the spring; the one that fell out does look suspiciously like
those used to close the shutter on a 3.5" floppy disk.

When I first powered it up I tried to format a 720kB floppy and it went
all the way through to track 80 but then said there had been an error and
the disk had not been formatted. I then tried a 1.44MB (didn't realise at
the time it was a DSDD drive) and had similar results.

The following day I tried it again with the 720kB floppy but the heads
moved all the way to the centre of the disk and the stepper motor started
slipping with a buzzing noise until I popped the disk and the OS trapped
the interrupt.

That's when I removed the drive and the spring fell out.

I cleaned the heads and checked the connectors both external and internal
to the drive, but no go.

I then confirmed from the spec that the NC200 has a 3.5" drive which
formats DSDD DOS compatible i.e. 720kB.

But the interface looks non-standard. It's only got 26 pins vs. 34 pins
on a standard PC FDD. It's a Z80 based machine so I will inspect the
motherboard to see what disk controller it uses. It may then be possible
to interface a PC FDD to it.

The easiest solution would be to find a scrap machine and change the
drive.

This machine only cost me 70p so fixing it makes no economic sense, but I
have this irrational desire to restore it to full working order!

Nick

A lot of the pins on standard floppy drives are grounds. If you can find the
data on the floppy drive interface, and cross reference it with a standard
PC floppy interface, you may find that the Amstrad interface is simply a
variation minus a few grounds. If it is, it should be fairly
straightforward to knock a cable together and replace the existing 3.5"
floppy with a standard one.

I used to occasionally work on Amstrad gear years ago and I do recall some
non-standard floppies. ISTR some early Compaq PCs went down that route as
well. Unfortunately I no longer have any data on the old Amstrad stuff.

Dave