Piedinature - Pinouts
S-Video to Composite Video RCA

Main Source: Tomi Engdahl (www.hut.fi/Misc/Electronics/circuits).

4 PIN S-VIDEO MINI-DIN Male


RCA Male Connector

 Y-Ground >-----+                +-----> RCA Composite Ground C-Ground >-----+  Y >------------+                +-----> RCA Composite Video C >-----||-----+       470pF Ceramic

Notes:
Larger capacitor values will also work, but cause picture to become "softer".
The impedances and signal levels not matched exactly right, but near enough to work accetably.