Date   : Sun, 08 Jan 2006 23:43:01 +0000
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: Modulator Interference & 3.5 HD disk drive

Paul J <peterbilt@...> wrote:
> I then reconnected the sony drive, and got the same problem
> accessing the drive, with bad interferrence on the modulator. I
> just kept repeating *CAT on the machine, and after several
> attempts it just sprang into life, with no interference. Since
 
Could be an intermittance contact fault where the vibrations just
happened to fix, or something.
 
> intial problems were, but I think the sony drive thought it was
> talking to a pc, and tried to communicate on the newer protocol.
 
There isn't a "newer protocol".  The drive just sends and receives
data bits at the speed of the clock pulses.  Some drives record
data at s strength indicated by the level of the "density select"
pin, but the majority of drives select density according to the
presence or absence of a second hole on the disk.
 
Hmm... That could have been it. Maybe there was some much or
something triggering the second hole detector, so making the drive
trying to read in High Density mode.
 
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
RISC OS Choices System - http://mdfs.net/Software/RISCOS