I'm trying to figure out the pinout on a SF Rush so I can wire it to a GBS-8200 CGA/EGA/YUV -> VGA board. The manual for Rush the Rock does not get into the pinouts of the wiring connectors.
It was connected to a NT-2701.
On the NT-2701, the input signal plugs into a connector P901. From right to left it looks like the pins go:
![](https://i.imgur.com/3uAvELc.png)
VSYNC
HSYNC
Empty
Empty
BLUE
Empty
GREEN
Empty
RED
-----
However, the connector from the Rush the Rock board has 2 black wires in the 3rd and 4th pin (from the left).
![](https://i.imgur.com/0OOrJlD.jpg)
I'm assuming these are ground? They go back to the same pin on the Rush the Rock board.
It would seem odd the NT-2701 would take a video signal without ground, but it's odd ground isn't called out on the connector. I'm assuming the NT-2701 can take ground on those pins marked "empty".
Is it likely this is correct? The GBS-8200 needs a ground for the input.
Thanks in advance for any help?