Hi all,
I'm using Daq USB-6211. Platform is MAC OS X. Labview version: 8.5.
The Daq sample at 250 HZ and each time take 250,000 data. So basically it sample 1 sec and continue sampling without stop. It's in differential mode.
The measurement starts with measuring the background noise of an ordinary coil. The coil is made up of thin copper wire with resistance 40 khm and inductance 0.1 Henry. There is a SR-560 preamplifier in between the Daq and the coil. Gain is 1000. it's in low noise mode and no filter is applied.
Now the energy spectrum shows there are 10K, 20K, 30K, 40K and 50K noise in it. They are very regular and I suspect they are produced by the Daq itself. It seems like its intrinsic clock? I really need to get rid of these noise to proceed. Also, I didn't connect anything except A1 and A9 in the daq. Is there anything we can do about the ground?
Sorry I mistakely click the "solution", which in fact this problem has not been fully solved yet. If this violate the rule, please let me know...
Thanks,
John
