Elekta Neuromag NM21283A, Руководство пользователя

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8 Basic measurements
44 NM21283A-A
2. Change the entry in the text field
expertLevel
and press
RETURN
.
After changing the level new entries should appear in to the prefer-
ences dialog. Also some new menus will appear.
3. Close the dialog by pressing Close .
The rest of the parameters in preferences settings dialog are explained in
Appendix B.
8.2 Selecting and running jobs
Before staring an operation you need to select what to do. You can select
the operation from the
Job menu. The jobs are described in more detail in
the following sections.
The “jobs” available are:
I/Phi Measure flux vs. current curves.
Noise Measure white noise levels.
FFT Measure spectra.
Signal Measure signal trace.
Tune Tune noise.
Tune (fine) Fine tune noise.
Tune (gate) Tune noise adjusting only gate values.
Tune (offs) Tune offset setting.
Manual tune Measure I/Phi curves fast to allow manual tuning.
Meas derivatives Measure parameter derivatives at operating point.
To run a measurement, select it from the
Job
menu, unless it is already
selected. The text on the “start button” changes according to the job so
that you can identify the currently selected job. To start a measurement
press the “start button”, to stop it, press the “stop button”.
There are two kinds of jobs. Some of them are continuous; they continue
until they are explicitly stopped. Others are one time jobs which are
started and they automatically stop when they are ready.
The acquisition system runs in three different states during the usage of
Tuner. It can be either idle, suspended, or active. When the program starts,
the acquisition is idle (unless somebody else is performing a measure-
ment). When a job is initiated the acquisition system is started and it
becomes active. When a job stops, the acquisition is suspended, not
stopped. This means that the front end (Collector program) is actually col-
lecting data continuously, but it is not send to the clients like Tuner. The
benefit of this arrangement is that if the measurement parameters are not
changed, a new measurement can be started without delays. The stop but-
ton has a dual action. When a measurement is running, pressing it stops
the current operation and suspends the acquisition. The label on the “stop