Noise on Unused GSR channels

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ffpresto
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Joined: Thu Oct 08, 2009 5:37 pm
Location: University of Waterloo

Noise on Unused GSR channels

Post by ffpresto »

We have two Active 2 systems (in two different labs). We recently ran a study in each lab, without GSR electrodes connected. One system appears to have recorded nothing, while the other has noise in these channels.

Is it possible we have a difference in configuration settings that is causing this? Or could there be some other difference in our systems?

Thanks
.. Frank

ERP Lab Manager
University of Waterloo

Coen
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Post by Coen »

The CFG file has no influence on the GSR channels.

Without GSR electrodes connected, you cannot draw any conclusions about the recorded GSR data.

Best regards, Coen (BioSemi)

ffpresto
Posts: 3
Joined: Thu Oct 08, 2009 5:37 pm
Location: University of Waterloo

Enabling GSR Sensors

Post by ffpresto »

Hi again,

I found a document with the following in it:

".... your ActiView CFG file must enable the use of sensors. Since most systems are sold without GSR measurement capability, the default configuration files that come with new versions of software contain a code that disables the sensors. To edit the CFG file, open it in Windows Notepad, and go to the section entitled [FreeChoice]. Look for the code:

AuxFree=0%

If you find this, change it to:

AuxFree=1%"

In one of our systems, our Default CFG file has:

AuxFree=1%2%3%4%5%6%

Would this create noise in the SCR (GSR) channel when we do not have electrodes attached? Should I change it to 0% when not collecting data and to 1% when collecting this data?

Thanks,
.. Frank

Coen
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Post by Coen »

The answer to both questions is: No.

Best regards, Coen (BioSemi)

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