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Dont use ungrounded laptops with no extra ground
When using a laptop on battery power, make sure to ground If you're using the acquisition board with a laptop that's running off battery power, you will have a "floating" ground. This will cause your signals to look extremely noisy. To fix the issue, connect the ground of the acquisition board to the building/table ground, otherwise the recording will pick up a lot of line noise. The best way to do this is with the "GND" screw terminals at the side of the board. You can, for now, also connect the shield (but not the center) of the back-panel "clock" BNC to your favorite ground. This may not be a good idea, since we might someday do something with the clock pin.whatever ground you're using for your experimental setup (perhaps a wall socket or a Faraday cage). You can either do this via the BNC connector (alligator clips work well for this), or by attaching a wire to one of the two dedicated screw terminals on the side of the board. The screw terminals are preferred because someday we may do something with the BNC. If you use the BNC, ground the shell of it to the wall, not the center pin. Connecting center pin of the BNC to ground will short your board and may fry the FPGA.
Beware of bad power supplies
Sometimes, aftermarket power supplies, mostly for laptops, but also for LED lights, or any other power brick, can cause a lot of line noise - try individually turning off equipment to isolate the offending one.
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