eDAQ Picostat, Руководство пользователя

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Chapter 4 — The QuadStat 55
Signal Display
The current signal is previewed scrolling across the display area. Note
that the signal is not being recorded to hard disk at this stage, and that
when the window is closed the signal trace is lost.
You can stop/start the signal scrolling by clicking the Pause/Resume
button .
You can shift or stretch the vertical Amplitude axis to make the best use
of the available display area. All changes to axis scaling are reflected
in the Chart and Scope main window, and vice versa.
Setting the Range
The Range pop-up menu lets you select the input current range or
sensitivity. The QuadStat has ranges of 2 nA to 1 mA. You should set
the range so that it is larger than the biggest current that you expect to
encounter during your experiment. If, during the experiment the current
signal exceeds the range, then the data will be truncated and therefore
lost.
Filtering
The QuadStat has low-pass filter settings (10 kHz to 1 Hz) for removal
of high frequency signals (‘noise’). The Off setting gives the full
bandwidth of the QuadStat which can be up to 16 kHz (but which may
also be limited by the characteristics of your electrodes and sample
solution).
The 10 Hz filter settings, and less, are highly effective for the removal
of mains hum (50 or 60 Hz interference) and, as a general rule, should
be employed whenever possible. However, low pass filters should be
used with care when performing pulse amperometric or voltammetric
experiments, or for other signals which are likely to exhibit fast rise or
fall times. For example if you are using the 10 Hz filter, then applied
potential pulses should be longer be longer than 100 ms, and
voltammetric experiments should have scan rates scan rates less than
about than 100 mV/s — otherwise excessive smoothing of the signal
may occur.