FMCG/Data Acquisition with LabVIEW Software: Difference between revisions

## Use the room coils to apply a low-frequency (~ 20 Hz) signal in the '''X''' direction. You should now see the fuzz being modulated at that frequency. To optimize it may help to set up another function generator to output a sine wave at the modulation frequency and use the SYNC output to trigger the scope. Zoom in so there are a few cycles of the 1 kHz frequency visible on the scope. If done correctly, you should see a row of 20 Hz-modulated "bulbs" when looking at the magnetometer output.

## The program can be set up to output the ''demodulated'' signal so that signal can be optimized. To do so, locate the row of four switches on the FPGA breakout box near the red '''ANALOG OUT''' BNC ports. Flip the switch(es) up for the channel(s) you are optimizing. This will connect the FPGA AO channels 0-3 (normally outputting the chirp) to the top row of red BNC ports. Connect these outputs to a second scope triggered by the source of the 20 Hz modulation (likely the BK precision generator). In the LabVIEW program, make sure that '''AO Type''' is set to '''X Magnitude''' and then in the '''Chan Settings''' box, click the buttons in the '''chans?''' column to send the demodulated X Magnitude signal to the second scope.