digital out cdrom to receiver

jammer

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Apr 8, 2008, 11:43:07 PM4/8/08

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I want to use the digital output of my LG GSA-4163B as input to my
receiver.
It is a weird 2-4 pin connector though.
What do I need to do this?

Arno Wagner

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Apr 9, 2008, 9:00:27 AM4/9/08

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Are you sure this drive has a digital output?

Arno

jammer

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Apr 9, 2008, 10:14:09 AM4/9/08

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On Apr 9, 9:00 am, Arno Wagner <m...@privacy.net> wrote:

Yes, see the bottom of this:
http://www.cdrinfo.com/Sections/Reviews/Specific.aspx?ArticleId=12429

Arno Wagner

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Apr 9, 2008, 12:49:45 PM4/9/08

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Aha. You do not have a 2+4 connector. You have a 4 pin analog connector
and a 2 pin digital connector. That one is very likely a standard
S/PDIF connector, one pin is ground and one a 1V level digital
output. I am not aware of internal to external S/PDIF cables,
so you likely have to roll your own. For this you can get an internal
S/PDIF cable, and add a standard RCA Plug (shild goes to outside).
If you accidentially swap the connections, you should not damage
anything, as the driver has a 75R series resitor. If your receiver
has an optical input, you need to get a powered converter
(likely expensive) as the signal levels are not enough to drive an
LED.

Arno

Arno Wagner

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Apr 9, 2008, 12:56:27 PM4/9/08

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> Arno

Update: It seems manu CDROMS actually have a TTL level S/PDIF output.
If yours has one too, you need a converter in any case and you
may damage your receiver if you connect directly. Sorry.

Arno

jammer

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Apr 9, 2008, 1:47:46 PM4/9/08

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This is my receiver:
http://www.yamaha.co.jp/english/product/av/products/ht/rxv1000.html

The PDF says it has coaxial digital inputs but I assumed they were all
optical (they all look the same)

1. I need something like:
http://www.pccables.com/cables/05026.htm

2. solder a female RCA on one end

3. use this:
http://cgi.ebay.ca/25-FT-Digital-Coaxial-RCA-S-PDIF-Extension-Cable-M-M_W0QQitemZ300214094830QQihZ020QQcategoryZ73384QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
to connect it to my receiver

jammer

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Apr 9, 2008, 1:59:58 PM4/9/08

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On Apr 9, 12:56 pm, Arno Wagner <m...@privacy.net> wrote:

Why do CDROM manufacturers do that?
I can't be the ONLY person that wants to connect my cdrom digital
output to my receiver.

jammer

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Apr 9, 2008, 2:09:16 PM4/9/08

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I found this site:
http://www.andrewkilpatrick.org/mind/spdif/

jammer

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Apr 9, 2008, 2:45:18 PM4/9/08

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I found 'S/PDIF brackets' that convert digital output from a
motherboard to an external connector.
Do you think this would work for my CDROM (not going throught the
motherboard)?

Arno Wagner

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Apr 9, 2008, 3:56:16 PM4/9/08

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I have no idea.

Arno

M.I.5¾

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May 8, 2008, 7:37:17 AM5/8/08

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"jammer" <james...@mail.com> wrote in message
news:a9d11496-93bd-4c6a...@n1g2000prb.googlegroups.com...

Actually, motherboard manufacturers do it as well. Most on board sound
systems output TTL level digital.

M.I.5¾

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May 8, 2008, 7:39:04 AM5/8/08

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"Arno Wagner" <m...@privacy.net> wrote in message
news:664aprF...@mid.individual.net...

The one advantage that TTL level S/PDIF outputs have is that they can be
converted to optical using just an LED and a 120 ohm resistor (though the
inclusion of an op amp to act as a buffer would be better.

Arno Wagner

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May 8, 2008, 10:34:54 AM5/8/08

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Previously "M.I.5¾" <no....@no.where.no_spam.co.uk> wrote:

OpAmp as buffer is a very bad idea, unless you use a very expensive
high-speed rail-to-rail 5V capable OpAmp. I am not even sure these
exist. Simply use a 5V digital driver and an appropriate resister if
you need more than the around 2mA a standard digital output can supply.

Arno