[fdutils] Need help with weird floppy issue

Simon Owen snowen at gmail.com
Wed Mar 8 16:36:15 CET 2006

On 3/8/06, Donnie Barnes <djbarnes at gmail.com> wrote:
> Taking a peek at a drive I certainly didn't see any potentiometer anywhere,
> but if given guidance on where to put one I certainly have the skills to give
> that a try.

The drives I've modified have been older 3" units, as found in PCW
machines and the Amstrad CPC / Spectrum +3.  Here's a picture showing
the motor on the back, with a peep hole to access the pot without
removing the cap: http://obo.homeip.net/speedmod1.jpg

I've had a look at a few 3.5" drives (all Sony, of different ages) and
I can't see a way to adjust it either.  They all seem to be beltless
direct-drive units, which are probably much more reliable, but less

Another possibility is to use multi-pass interrupted formatting.  I do
something similar to write mixed-mode track patches to simulate 'weak'
sectors for retro copy protections.  The first pass would lay sectors
in the correct positions later on the track, with the start of the
track holding the necessary dummy sectors to aid their positioning. 
One or more repeat passes would then complete writing of the earlier
sectors, with the controller interrupted before it overwrites the
later ones.

It's a bit of a hack, but it can help work around the problem of
needing fixed size/gap multiples for mixed-size formatting.  I see if
I can work out a suitable layout that will do it - it's not critically
tight so I'm reasonably hopeful.

A CatWeasel would certainly have no problem at with this, but it'd be
nice to have a solution available to people with only standard

Best regards,


fdutils mailing list
fdutils at tux.org

More information about the Fdutils mailing list