Amstrad CPC 6128 Floppy problem - test-drb@ccmp.vtda.org

29 Nov 1999

On Nov 29, 19:02, Tony Duell wrote:
...
  >
 > I have a CPC6128 which reports that there is no disk in the drive when I
...
  > try to run a program or even |dir.
 >
 > I have opened the box up and it looks as if the drive isn't spinning up.

...
   I don't notice
 a disk-inserted sensor on the FD1 schematic in the 8256 service manual
 (which I am pretty sure is the same drive), though, and it appears to
 detect a disk in place by looking for index pulses (the circuitry around
 Q5-Q8). 
I think that's right.  The classic symptom of the very common drive belt
problem is that the disk isn't detected.  Since the motor is pretty quiet,
yo might not realise it's running but simply not driving the spindle.

...
  These drives are well-known for suffering from drive
belt problems, which
 of course results in the motor spinning but the disk not turning. Could
 that be the problem with your drive? 
*Very* common.  After a few years disuse, the belt goes slack.  In a pinch,
you can replace the belt with a flat rubber band to prove the rest of the
drive is operational, but it won't be completely reliable.  The belts are
easy to get, at least here in the UK, and quite cheap (a pound or so) if
you don't buy the branded Amstrad spare part.  However, they're flat belts
and not very stretchy, unlike most round- or square-section cassette belts,
so you do need to get the right size.

-- 

Pete						Peter Turnbull
						Dept. of Computer Science
						University of York