S-video to composite problem

[Al]

I have a video output device which has only an S-video output. I
purchased an s-video to composite adaptor. It's supposed to convert the
s-videooutjput to NTSC composite. It doesn't work.

It didn't work on three different NTSC input monitors. The monitors do
work fine as a NTSC composite video from a video camera works with all
of them. The s-video also works as it works with an s-video input on
another system. So what is wrong here?

I checked the so called composite output from the adaptor with an
'Oscope. The levels were only aobut 0.4 Vpp. I suspect this is the
problem.

Aside from buying an active converter for $30 for so, what can I do?

Any hints would be appreciated.

Al

 

[Luhan Monat]

Al wrote:

I have a video output device which has only an S-video output. I
purchased an s-video to composite adaptor. It's supposed to convert the
s-videooutjput to NTSC composite. It doesn't work.

It didn't work on three different NTSC input monitors. The monitors do
work fine as a NTSC composite video from a video camera works with all
of them. The s-video also works as it works with an s-video input on
another system. So what is wrong here?

I checked the so called composite output from the adaptor with an
'Oscope. The levels were only aobut 0.4 Vpp. I suspect this is the
problem.

Aside from buying an active converter for $30 for so, what can I do?

Any hints would be appreciated.

Al

Sounds like that device has maybe 2 resistors. Guaranteed to lose over
half the signal level trying to mix the luminance and color signals
together.

May be a lost cause without an active mixing device.

--
Luhan Monat: luhanis(at)yahoo(dot)com
http://members.cox.net/berniekm
"Any sufficiently advanced magick is
indistinguishable from technology."

 

[Si Ballenger]

On Sun, 15 May 2005 19:15:26 GMT, Al <no.spam@wanted.com> wrote:

I have a video output device which has only an S-video output. I
purchased an s-video to composite adaptor. It's supposed to convert the
s-videooutjput to NTSC composite. It doesn't work.

It didn't work on three different NTSC input monitors. The monitors do
work fine as a NTSC composite video from a video camera works with all
of them. The s-video also works as it works with an s-video input on
another system. So what is wrong here?

I checked the so called composite output from the adaptor with an
'Oscope. The levels were only aobut 0.4 Vpp. I suspect this is the
problem.

Aside from buying an active converter for $30 for so, what can I do?

Any hints would be appreciated.

Al

You may just need a 470pf capacitor from Radio Shack. I made the
composite to S-video adapter below from the below schematic. This
simple setup seems to work both ways. www.geeks.com has the
adaptes for ~$1.50

http://www.tkk.fi/Misc/Electronics/circuits/svideo2cvideo.html
http://www.geocities.com/zoomkat/winnov.htm
http://www.geeks.com/details.asp?invtid=4PINS-VIDEO&cat=CBL