FD400 drive troubleshooting - test-drb@ccmp.vtda.org

25 Nov 2007

...
  From: cclist at sydex.com
 To: cctalk at classiccmp.org
 Date: Sun, 25 Nov 2007 10:11:29 -0800
 Subject: RE: FD400 drive troubleshooting

 On 25 Nov 2007 at 9:50, dwight elvey wrote:

  I was thinking about Tony's idea of the
multiple and it occurred
 to me that there was an issue. We've been thinking of the
 flashes as instantaneous strobes while they have duration. 
 Dwight, I think it's worse than that. There's also the idea of
 "persistance of vision" that gets in the way and also makes the
 strobe disc work--our eyes do not have instantaneous response and the
 only reason a strobe disc really works is because a fixed pattern is
 drilled into our optic nerves many times per second. Were this not
 the case, one could have a 45 RPM strobe disc, not with 400 bars, but
 with, say 4 or 50--but our eyes would likely not register these as a
 single continuous event.

 Of course I haven't tried this yet and I really should.

Hi
 That is why I think the spiral with bars would work the
best. Persistance from adjacent bars would only be a
small issue at the tops and bottoms of the bars. The
eye would tend to follow the spiral.
 Such spirals could be made for any RPM. In the case
of disk drives, one could make three different spirals.
Each for a percentage below and a percentage above
the exact one. This way, one could quickly see if the
speed were within a specific tolerance.
Dwight

_________________________________________________________________
Put your friends on the big screen with Windows Vista? + Windows Live?.
http://www.microsoft.com/windows/shop/specialoffers.mspx?ocid=TXT_TAGLM_CPC…