"Meat Plow" wrote in message
...
On Sun, 02 Dec 2007 09:08:57 +0000, N Cook wrote:

Meat Plow wrote in message
...
On Sat, 01 Dec 2007 17:26:24 +0000, N Cook wrote:

Meat Plow wrote in message
...
On Sat, 01 Dec 2007 12:32:20 +0000, N Cook wrote:

Someone asked me to look at this very expensive unit , but I
declined.
Not seen and model number unknown.
Apparently there is something called OPC that checks the material
of
the
blank media. About 2 out of 10 attempts to record, it drops out at
this
OPC
check stage, equally so for the 2 makes of disc he uses.
As it is still useable I declined to look at something that may
well
end
up
worse, and I suggested he try some other makers discs.
Any other advice ?

http://en.wikipedia.org/wiki/OPC_Data_Access

Don't know if this is related to your situation but read it anyway.

I've only previously come across OPC meaning optical photo-conductor
surely this OPC means Optimum Power Control rather the Ole Process
Control

Ok I've never heard of it before obviously. But I would assume it is an
a control found in every optical recording device and not unique to the
device you reference.


I did a bit of reading up about the technology in and around
http://www.chipchapin.com/CDMedia/cdr3.php3

Good read and it answered a couple questions that have been floating in
the back of my head.

1. Why blank CDR media Branded as Music CDR exist and why it is more
expensive.
2. What actually was going on in the power calibration part of
the debugging information I sometimes read in K3B DVD/CD burner for Linux
KDE desktop.

One thing though. The article states that stand alone CD burners need to
use discs with special info encoded in the wobble on a blank CDR but I
have never needed to use Music branded media in our Fostex stand alone
studio burner.

Many makes take no notice of whether the disc is a genuine 'audio' one or
not. A notable exception used to be burners from Philips. A friend of mine
bought what appeared to be a brand new Philips disc to disc audio recorder,
from a dealer at a radio rally. He paid silly money for it - a fiver as I
recall. The dealer had a whole stack of them on his stand, and most were
marked "will not record". My friend was not particularly bothered by this,
as all he was interested in was the playback capability, which both fitted
decks, have. However, when he got it home and tried it, using a CDR disc
that he would normally use in his computer burner, it was apparent from the
error message that he got, that it was not recording because there was
something about the media that it didn't like. The next day, he popped into
a HiFi shop that he passed on his way to one of his calls, and asked if they
knew what the error message meant. The shop guy immediately told him that
it was a question that he often got asked, particularly by people who had
bought second-hand Philips units off ebay, and that all that was needed, was
to use recording duty-paid discs, which said "audio" on them, and contained
the digital watermark. He duly bought some, and when he got them home, the
guy was quite right, and it recorded perfectly.

Arfa