Text 55961, 49 rader
Skriven 2009-07-18 20:42:18 av Jeff Guerdat (1:124/311)
     Kommentar till en text av August Abolins
Ärende: Re: mac/pc keyboards anyone?
====================================
On 07/18/2009 09:27 PM, August Abolins wrote:

> The G3 has a slot for the CD.  According to the line printed on a label:
> "iMac/600/GR/256/40/CDRW/Ultra/56k/FW/VGA"..  I surmise that it's 600 Mhz,
> 256meg ram, 40gb hdd, CD burner, 56k modem.  I don't know what "GR", or "FW"
> would mean.

I'll wager FW is for FireWire.

> I have a OS X Panther 10.3. Install disc 1. But there's a major scratch on it
> near the outer edge.  The PC errors out at boot up and prompts for the CD. 
But
> the CD fails.
...
> The other bright idea I had was to create a new CD from the scratched version
> hoping that the error-correction in the process might correct the problem.
> There are two small radial scratches near the edge of the CD. The cut right
> through the label. You can see light passing through when holding the CD up
to
> the light.

When faced with a damaged CD, I always try to copy it since the ECC can 
take it's sweet time trying to overcome the problem.  I'll also use 
different drives since each one will have it's own characteristics that 
may get past the problem when others fail.  However, having a scratch at 
the outer edge would seem to not be as problematic as an inner radius 
since the disc is typically read from the inside out as opposed to a 
magnetic drive which reads from the outside in.  No guarantees since it 
depends on how the disc was authored.

The ECC and level detection is important in how a particular drive 
handles such scratches.  I had an audio CD I was trying to copy back in 
my Kodak days when working on the high-speed (6x!) writer in the early- 
to mid-'90s.  They actually got me a new disc since such damage couldn't 
be easily created in the lab.  The Philips 2x writer would successfully 
copy the disc while the Kodak one failed.  Analysis determined that the 
read threshold was set low enough on the Philips drive to read the 
reduced signal (reduced since the reflective surface had been scratched 
through).  Readjusting the threshold on the Kodak writer allowed the 
disc to be read.  Trying the same disc on other drives can be a valuable 
recovery technique.

-- 
Jeff Guerdat

Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?
--- Platinum Xpress/Win/WINServer v3.0pr5a
 * Origin: FidoTel & QWK on the Web! www.fidotel.com (1:124/311)