ADInstruments Bio Amp, Руководство пользователя

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Bio Amp Owner’s Guide
28
EEG Mode
The
EEG Mode
checkbox changes the available filters of the Bio Amp to suit
EEG applications. When this checkbox is selected, the
High Pass
pop-up
menu gives filter settings of 0.03, 0.1, 0.3 and 1 seconds, and the
Low Pass
pop-up menu gives filter settings of 3, 10, 30, 60, and 120 Hz. It is a
convention in EEG to deal with high-pass filter settings in terms of seconds
(giving the time constant of the first-order filter).
Inverting the Signal
The
Invert
checkbox provides a simple way to change the polarity of the
recorded signal without having to swap the connections to the recording
electrodes.
Units
Click
Units…
to display the Units Conversion dialog, with which you can set
the units for the channel and, using waveform measurements, calibrate the
channel. The waveform in the data display area of the
Bio Amp dialog is transferred to the data display area of the Units Conversion
dialog. (Use the Pause button to capture a specific signal.) The units
conversion only applies to subsequently recorded signals, so it is more limited
than choosing
Units Conversion…
from the Channel Function pop-up menu,
as it does not allow conversion of individual blocks of data.
DC Restore
The
DC Restore
button is available for the Dual and Octal Bio Amps. It
provides a quick way to bring the recording trace back to zero. It is for use
with the 0.02 Hz high-pass filter, since the trace can take a long time to zero
automatically at that setting. In later versions of LabChart the
DC Restore All
command from the Setup menu performs this operation on all Bio Amp
channels.