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Noise

Open LibiF opened this issue 6 years ago • 4 comments

Hey, The data I record suffers from strong noise fluctuations at the nyquist frequency of the probe (15 kHz oscillations). It is also periodic in some sense, and oscillations repeat at 50,100 Hz (so they are "carried"/amplified by electrical noise). I was wondering whether anyone else had experience with this kind of noise/how to solve it?

Here is an example: image

LibiF avatar Jul 04 '18 15:07 LibiF

Hi - it looks like it might be possible that the data is not being loaded properly, which I'm inferring based on the fact that it shifts in time from channel to channel. Does your params.py have n_channels_dat=385 (if you acquired with spikeGLX, because there are 384 channels from the probe and a 385th from the synchronization information). If you use kilosort, ops.NChanTOT should be 385, and if you load in matlab, also use fread(fid, [385 n], '*int16'). Let me know if that might be the problem?

nsteinme avatar Jul 05 '18 16:07 nsteinme

Hey Nick, it actually is the problem (or at least one, I am checking to see if all works out)... Should number of active channels (ops.Nchan) be set to 374/375 accordingly?

LibiF avatar Jul 07 '18 06:07 LibiF

374!

On Sat, 7 Jul 2018, 08:48 LibiF, [email protected] wrote:

Hey Nick, it actually is the problem (or at least one, I am checking to see if all works out)... Should number of active channels (ops.Nchan) be set to 374/375 accordingly?

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nsteinme avatar Jul 07 '18 08:07 nsteinme

Thanks so much!!! I think it finally looks good=]

LibiF avatar Jul 07 '18 08:07 LibiF