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F3 Technical

The F3 board has a few extra connectors, most of which I have not figured out yet. You can see the two marked "3P" and "4P" which I am assuming are Player 3, and Player 4. There is also a connector for a Spinner to be used with Arkanoid Returns and Puchi Carot, but I'm not sure which one it is yet.
Here is the switch to change between a Joystick and a Spinner controler. You also need to go into the PCB setup to change it there as well.
The test button is in the upper Right hand corner of this picture. On the board itself, it is in the lower Right corner, just above the connectors. You will need that if you don't have a Jamma test button wired up. This will get you into the setup menu.

This is another 4 pin connector. Also note above the pot marked "VR1" That is NOT a volume control. It is used to adjust the voltage at the PCB. Don't mess with it or you will screw the PCB up.