I think i have the solution to your problem.
If the S-video out on your computer is a 7-pin female connector, and
the S-video in on your TV is a 4-pin connector, you just need to use a
standard S-video cable.
- HELSINKI UNIVERSITY OF TECHNOLOGY -
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What if my PC graphics card has a 7-pin S-video connector instead of
The four pin S-video connector as shown above is the standard
connector for carrying S-video. Those seven pin connectors seen on
some PC graphics cards are non-standard connectors for carrying
S-video. The use of the pins on those seven pin connectors is not
standardized and can vary from manufacturer to manufacturer. (For some
strange reasons some manufacturers in PC industry just keep constanly
breaking the industry standars and create lots of confuzion to users
when doing so).
Generally the four pins on those 7-pin connectors on the same places
as the standard four pin S-video connector have practcly always the
same fuctionality as those pins in S-video connector. The other three
pins can have then some extra signals which are not part of S-video
(usually some pins of those carry composite video and some control
signals, but the use of those three extra pins vary quite much). So if
you encounter 7 pin connector for S-video, then forget the three
center pins... just use the four on the standard positions. The
circuit shoudl work with those connectors as well.
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You must try a standard S-video cable which will be available in most
TV stores. If you need to know where you can get one, I can search it
out for you if you give me some details of where you are situated.
Please let me know if this works out for you, or else, there may be
something else that is causing the problem. I will continue the search
for a solution in this case...