4 PIN S-VIDEO MINI-DIN Male
RCA Male Connector
S-Video (Y/C) uses a 4-pin mini-DIN connector to carry luminance (Y) and chrominance (C) on separate conductors, each with its own ground return. Composite video (CVBS) combines both signals onto a single 75-Ω coaxial line, typically terminated with a yellow RCA plug, at 1 V peak-to-peak including sync. This passive adapter merges the two S-Video signal lines into one composite output by AC-coupling the chrominance through a ceramic capacitor, avoiding a full Y/C encoder; signal quality is visibly lower than a proper encoder because impedances and signal levels are not perfectly matched. The composite video signal format is governed by ITU-R BT.470-7 for both PAL (625-line/50-field) and NTSC (525-line/59.94-field) systems.
| S-Video source | Via | RCA composite output |
|---|---|---|
| Y-Ground + C-Ground | direct | Composite ground |
| Y (luma) | direct | Composite video |
| C (chroma) | 470 pF ceramic capacitor | Composite video |
| Pin S-Video | Description | Pin RCA |
|---|---|---|
| 1 | Ground (Y) | Ground |
| 2 | Ground (C) | Ground |
| 3 | Y - Intensity (Luminance) | Signal |
| 4 | C - Color (Chrominance) | Signal through 470pF Ceramic Capacitor |
Notes
- Larger capacitor values will also work, but cause picture to become “softer”.
- The impedances and signal levels are not matched exactly, but near enough to work acceptably.
- S-Video luminance is 1.0 V p-p at 75 Ω; chrominance is approximately 0.3 V burst (PAL) or 0.286 V p-p (NTSC) at 75 Ω. The composite output should present 1 V p-p into a 75-Ω load.
- Both ground pins (Y-ground and C-ground) are tied together and connected to the RCA sleeve.
- This adapter produces a standard-definition analogue composite signal only; it is not suitable for high-definition sources.