Please help me understand s-video connection from my PC to Television

[Fotis_Greece]

My VGA card is an ASUS 8460 Ultra which has a. s-video out for connection to the TV. I am mostly interested in using it for viewing DVD movies in my big TV Set. I have some questions to ask since I am a bit confused with cables issues:
1)I have realised that the best quality connection is connection s-video to s-video to the TV set (if it has such input). Is it true?
2) Most televisions I have seen do not have s-video input but only scart (in europe where I live). Is it possible this scart to actully be s-video input with the appropriate adaptor? I mean I have bought an s-video cable which ends by itself in a scart connector. Is my TV set now receiving s-video signal or the scart "kills" the quality?
3) What is the maximum allowed length of an s-video cable so as not to lose quality
4)I have seen s-video ports with 7 or 4 pins. Is there a difference?
5) In the site of the software TV Toll (http://tvtool.info/index_e.htm) the author says that the s-video connection has the disadvantage of having to use two cables, one for Luminance and one for Chrominance. I can't understand this, where does the second cable connects since the VGA has only one port? <br> (Here is what he says:Especially TVs of the higher price segment offer also a S-VHS input. The 'S' means super and shall clarify that this standard offers a better quality than normal VHS. The S-VHS standard transmits video signals on two lines. On one line you find a b/w picture and on the other line there is the belonging color information. By splitting the picture into these parts the interference effects can be avoided. Also most device which can handle S-VHS use the full resolution of the PAL or the NTSC standards. Therefore you get a sharper picture than with VHS. The disadvantage is that you need two lines instead of one. Also you need special connectors when making a cable since the normal cinch cables can´t be used.If you want to make a S-VHS cable you have to use two lines of course, one for the luminance and one for the chrominance. So if your cable must be 15 m long you have to buy 30 m, what can make the connection expensive )<br>
6) If my TV set is long away from the TV set how can I connect it without losing quality, is there such a thing as repeater like the way we use firewire cables for long connections networking.

I would really appreciate if you could please someone clarify these issues to me. Thanks in advance

[oddyseus]

1). Yes it is.
2. There r scart cables that r labeled as 'full21 scart' and realize the svideo input if your tvset is expecting such a signal.
3. I would suggest not to overcome 100cm in length.
4. 7pin svideo r special ports that implement special functions per appliance. Standard din svideo is 4 pins.
5. The 2 signals r implemented through 2 cables in a common coating.
6. U can manufacture a long svideo cable but be prepared for quality loss. I dont think I have ever heard of repeaters in svideo cables.

[Fotis_Greece]

Originally posted by oddyseus
5. The 2 signals r implemented through 2 cables in a common coating.

What do you mean by this, I've alway known the s-video cable is one cable. Do I have to make it myself or there are ready to buy ones? Do I need an adaptor for there two cables? Do these two cables are joined at the ends so to fit in the one port of the PC and the TV's?
Thank you very much for your answer ( I hope I am not getting boring)

[oddyseus]

For all our concerns its one cable. The internal structure of it is transparent and irrelevant to us.

Svideo is made up of 2 cables as scart cables r actually 21 of them in a common coating. I hope this makes it clear.

U just would out and buy a svdieo cable that has a mini-din at one end and a scart at the other. If u can't find one just buy a svideo with mini-din both ends and a scart adapter for svideo.

[ulfschack]

Additionally on q4: One (or two even, if no common ground) of the seven pins has composite signal as well. That's why you can get thoses dummy adapters to convert to an RCA plug from your "s-video" port for the people that don't have s-video capable TVs.

I can't account for the last 1-2 pins tho, but Odysseus' "special function per appliance"-thing seems reasonable.

cheers

[mpucoder]

Are you talking about the 7-pin mini din found on capture/tvout cards? On my ATi it has the normal 4 (Y, C, and 2 grounds) plus composite and 2 audio. It also comes with 2 breakout cables with a 4-pin mini-din and the familiar yellow/black/red RCA jacks.

[ulfschack]

I must missunderstand you.

Does two of the seven pins on the plug that goes into your graphic card carry audio?

Where does the breakout cables spring from?

[mpucoder]

Yes, the card is a tuner/capture/tvout card. There are 2 7-pin mini-dins on it, one for input, one for output. This is where the breakout cables attach. The input audio is routed to the output audio if either composite or S-Video is selected as the capture source, otherwise the output audio is the tuner. The output dongle actually has a mini-phone plug (not RCA, as on the input), and goes into the audio card.

[pomo]

I see there was some misunderstanding here about that thing with the two cables ;-)
I may clarify:
as we know S-video is that thing you plug in somewhere.
Here comes the point:
S-VHS is not S-Video , S-VHS is the name of a cassette standart (it's a super VHS), it's a medium that stores video.
The S-VHS casette saves the video different to a normal VHS in two lines, which is luminance an chrominance.
Further the text sais that for S-VHS, you need two Cinch-cables (where Cinch is not S-Video). As far as I know, a S-Video-connector (as it has more pins) works that way to (with seperated luminance and chrominance), such does the Scart (I guess).

hope I have clairified things up some little
(I may have said certain things that are not true, this is what I guess due to some small knowledge and locigal deduction).

Question btw:
I guess that S-video and Scart are equivalent in quality as they transmit the same signals. the difference in the huge number of pins of a scart is because the scart first of all also transmits two-channel audio and second: it does this in two directions (from VHS-receiver to TV and vice versa). My question in this is: is this true the way i believe it to be ?

[oddyseus]

Scart is a European connector that has 21 pins, capable of transfering, composite video, s-video, rgb video, and 2 channel audio at the same time.

What actually is carried is dependant on the transmitting appliance. Your dvd player is capable and is actually transmitting rgb or s-video signal according to your settings. The problem is that 'is your tv set capable of receiving either of them?' If not, what u actually see is the composite signal that is transmitted all the time along.

Both video signals r travelling through the 21 'chanells' of the scart cable.

On the other hand a normal vhs vcr is only capable of transmitting composite video, whereas a s-vhs can provide u with high quality s-video video signal.

[vascosaavedra]

Hi.
In your opinion, what type of input produces the best image quality results?
The s-video input or the scart?
What are the main diferences between them?

[Zhnujm]

just read the post above yours ;) ,it explains everything.

[TheWEF]

Originally posted by oddyseus
If not, what u actually see is the composite signal that is transmitted all the time along.

this means:
if your tv-out can provide s-video only and your tv only "understands" composite you will see a black&white picure.

if a tv has an s-video plug you know that it understands s-video.
if it has a scart plug only you don't know, but it's possible.

wef.

[DDogg]

This may be a good place to ask one of you old solder hounds if you have a pinout diagram for 8 pin Din RGB. I have an old Janeil monitor that accepts separate Chroma/Luma as well as RGB III or RGB I. I think I will hack up a S-video cable to connect from the s-video out on my DVCam to the sep Chroma/Luma, but I am also curious what the RGB I & III was for. Also, for some reason I remembered DIN as either 5 or 9 pin, but I only count eight including the middle pin with this one. Anybody remember this stuff?

[mpucoder]

The only din-8 rgb I know of is ttl level (equivalent to CGA) - here's the pinout:
Pin Description
4 Red Video
1 Green Video
5 Blue Video
3 Ground
2 Horizontal Sync
6 Vertical Sync


There is also a din-8 connector used by Sony that carries audio, composite video, and S-Control (remote control). There's a pinout at http://www.whatvideotv.com/articles/hardware/images/200102_scart_4.gif

[Slogra]

I also found a nice Scart article on that site:
http://www.whatvideotv.com/articles/frame.html?http://www.whatvideotv.com/articles/hardware/200102_scart.shtml

[DDogg]

mpucoder, thanks! Yeah, I think it probably was CGA as this was a monitor I found in my attic that I had bought as a substitute for a Commodore 64 monitor way back when. Hmm, my daughter was in her teens then, now 33 and getting married in a few days...How time does fly. Anyway, it sure works darn good as a passthrough monitor for my DV editing setup and the price was right.

[mpucoder]

Ah, C64 - I have a C128 with a DIN-8, but it's Y/C, not RGB. For those not familiar, the C128 was a strange machine with both 6502 and Z80 processors, both VIC and CGA, ie a dual personality that could run C64 programs as well as CP/M.
Anyway, this is probably what you are looking at http://www.computerrepairservice.com/cables/co_C128C64CVideo.html

There are lots of connector pinouts at that site http://www.computerrepairservice.com/cables/menu_Connector.html