rb said:
I'm planning to send audio from my old pc (win XP) to a TV.
The TV has the standard yellow coax looking plug.
My pc has a small NIC card in back with line, speaker, and audio. The audio
plug uses a small pin plug. No other audio output things on the frame.
If I find a cable to hook these up, will that be OK on audio?
If not, what a good choice for a NIC or some other way?
The first thing you do, is positively identify what the jack is
on the TV set. TV sets use a standard coloring scheme for at
least some of the jacks.
Yellow RCA jack = composite video only
White RCA jack = left audio channel
Red RCA jack = right audio channel
On the TV set, you may see the three of those clustered together.
The fact that the audio and video have separate jacks, tells you
the standard for the yellow jack, doesn't carry any audio.
Some TV sets have no provision to send them audio. Mine, for
example, requires that I use my stereo to carry the audio
portion of the program. There is only a composite video jack
on the front of my small portable TV set.
To connect to a particular TV set, I would need two things.
1) Composite video output from the graphics card. On the graphics
card, there may be a "TV" output. It will be a black, circular
DIN connector, with room for multiple pins on it (4 or 7 or 9, it
varies). Again, there are standards that are roughly adhered to.
Four particular, symmetrically placed pins on the outside circumference
of the DIN connector, yield S-video (Y, C, GND, GND, carrying luma
and chroma). An adapter, converts from DIN pinout, to an RCA jack.
That RCA jack is what would be connected, via 75 ohm video coax,
to the yellow jack on the TV. Note that you cannot use audio
cables for this one - the cable must be specifically for video.
The key ingredient is "75 ohm" and "coax".
2) For the audio, that comes from the sound card. The sound card
may have three to five 1/8" stereo jacks on it. Again, there
are color standards, and green is usually the "Lineout". To go
to the TV set, you need a 1/8" stereo plug on one end, and
two RCA female jacks on the other end. You can use a pair of
audio cables with RCA males on each end, to connect to the TV.
For cables, you can either use video rated cables (can be used
for video or audio), or audio cables (good enough for audio).
For audio, the cables don't have to be "75 ohm" or "coax".
If you were stuck on a desert island, and had only zip cord
(appliance two wire cord) and male RCA plugs, you could make
acceptable audio cables for carrying line level signals.
So the signals come from two separate cards on your PC, and have
adapters needed for each.
*******
For video:
This is the DIN pin pattern for S-video.
http://www.tkk.fi/Misc/Electronics/circuits/svideo_connector.gif
This one is DIN S-video to composite - yellow colored to go to yellow TV jack.
http://www.sandberg.it/img/prod/lg/502-34_lg.jpg
This is the "bullet" version of the same adapter. It is more compact
and these sometimes come with the graphics card in the box.
http://www.tvcables.co.uk/images/items/AD009.jpg
*******
For audio:
This goes into the green Lineout on the sound card. There are two
RCA jacks on the opposite end. One jack is "white" for "left audio",
and the other jack is "red" for "right audio"
http://www.radioshack.com/product/index.jsp?productId=2103225
Radioshack wants a fortune for cables, so I might shop around
for them. Finding "Monster" brand cables in their store, is not
exactly good for the customer's pocketbook.
One way to make cables, is to get coax cable with the thin wire
in the center of the connector. The connectors on the end are
threaded. Usually that kind of wire is cheap and commonly available.
You can stick one of these on either end of the cable, to convert
to RCA format.
"F" Connector to RCA.
http://www.radioshack.com/product/index.jsp?productId=2103580
Also, in the video description above, the TV set could have a
DIN connector (black, with four pins), and if that is the case,
then an S-video cable could be used, instead of the DIN to
RCA adapter. In that case, the cable carries S-video (Y,C,GND,GND)
from the video card, right to the TV set. Expect that cable
to be suitably overpriced as well.
There are other standards for TV, now available on new LCD TV sets.
Some of those are easier to connect up. But on the computer end,
support is still far from perfect. There are only a few computer
graphics cards, with fully featured HDMI. A proper HDMI output
now, carries both digital video and digital audio, so separate
cables are no longer needed. Only one cable to do the whole
job. But many early computer HDMI connectors lack the audio
channels. For a lot of people, audio still has to be solved
separately.
Paul