Sega Genesis/MD Model 1 C-Sync Questions

Hello everyone! I made a custom Sega Genesis/MD Model 1 RGBS cable using a spare VGA cable. I have a breakout adapter (VGA female connector with solder terminals) on the other side that splits RGB, C-Sync, +5V, and ground into wires for a project I'm working on.

After wiring everything up, I noticed I'm getting 4V on the C-Sync pin of the VGA side (uses the H-Sync pin). Is this normal? I do have +5V running to the ID1/SDA pin next to the H-Sync pin. Is it cross-talking?

I have also heard some things about modding the console for a better C-Sync signal so how can I do that? Will a sync booster still be needed?

Any help will be highly appreciated!

EDIT: I should probably add that my console is a VA6.5.

 

The c-sync mod involves cutting the trace between pin 7 of the din port to the cxa ic pin 10 (c-sync in) and connecting pin 11 of the ic (c-sync out) to pin 7 via a 220 uF cap and 75ohm resistor in series.

Same thing on the master system. Wonder why Sega did it this way? I had to do this mod to get any picture at all.

 

Ah ok. I'm not having trouble with C-Sync on my system (that I know of) so I'll do that as a last resort. I'll keep it in mind when I get a Master System.

So I tested the C-Sync pin of the DIN connector on the motherboard and I got 4.55V on it. I guess my cable wasn't cross-talking with the +5V line after all.