I'm using a pcie 6361 with a scb-68 breakout board to measure two signals simultaneously. My problem is that I am seeing a small trace of signal A in signal B and vice versa.
A simpler explanation of the same problem: if I connect a signal to any of the analog inputs, I can see that signal on every other analog input (very small of course, but present). Is there any way to eliminate that unwanted ghost signal?
you have discovered crosstalk due to the multiplexing ADC sample&hold capacitor settling time.
See spec of your card.
Minimize it by
reduce the samplerate and
reduce the source impedance
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