Histogram Mode
Successive measurement results are converted into a histogram.
The number of bins along the horizontal axis can be set by the
user through the Settings -> Stat menu. The bins in the histogram
are autoscaled based on the measured data. Limits, if enabled, and
the running mean value X are shown as vertical dotted lines. The
center of the graph is indicated by a filled triangle on the X-axis. The
corresponding numerical value is displayed below it and so is the
scale factor. Enabled limits affect the autoscaling so as to visualize
the current measurements and the set limits simultaneously.
Trend Plot Mode
This mode is used for observing periodic fluctuations or possible
trends. A trend plot terminates (if HOLD is activated) or restarts
(if RUN is activated) after the set number of samples has been
completed. The trend plot is always autoscaled based on the
measured data, starting with 0 at restart. Limits are shown as
horizontal lines, if enabled.
Remote
When the instrument is controlled from the GPIB bus, and the
remote line is asserted, or when the instrument is controlled from
the USB bus, then the presentation mode changes to Remote,
indicated by the label REM on the display. The main measurement
result and the input settings are displayed in this mode.
Hard Menu Keys
These keys are mainly used for opening fixed menus, from which
further selections can be made, for instance by means of the soft
keys.
Input A
By depressing this key, the bottom part of the display will show the
settings for Input A.
The active settings are in bold characters and can be changed by
pressing the corresponding soft key below the display. You can also
move the cursor, indicated by text inversion, with the RIGHT and
the LEFT arrow keys to the desired position and then make the
selection by pressing the UP or the DOWN arrow keys. You can
also use the ENTER key.
The selections that can be made in this menu are:
•
Trigger Slope: positive or negative, indicated by corresponding
symbols
•
Coupling: AC or DC
•
Impedance: 50 Q or 1 MQ
•
Attenuation: 1x or 10x
•
Trigger: Manual or Auto (always Auto 10/90 % when measuring
transition times).
•
Trigger Level: If Manual has been selected, the absolute level can be
adjusted with the up/down arrow keys or by entering a numerical
value from the keyboard.
•
Filter: On or Off. Pressing ENTER or the soft key below the text
opens up the Filter Settings menu. See below.
You can select a fixed 100 kHz analog
filter or an adjustable digital filter. The equivalent cutoff frequency
is set via the value input menu that opens if you select Digital LP
Frequency from the menu above.
Input B
The available settings under Input B are equal to those available
under Input A.
Settings
This key accesses a range of more sophisticated instrument settings
that usually need not be changed for basic measurements. The
figure below shows the display after recalling the default settings
via the USER OPT menu.
A detailed description of all the possibilities is far beyond the scope
of this introductory manual. See the User’s Manual for full details
on functions mentioned and unmentioned here.
Meas Time
This value input menu is only useful if you select a frequency
function. Longer measuring time means fewer measurements per
second but gives higher resolution. You can change the Measuring
Time by entering a numerical value, or you can use the UP/DOWN
arrow keys to increase or decrease the current value.
Burst
This settings menu facilitates measurements on pulse-modulated
signals and is only useful if Frequency Burst is the main
measurement function.
Both the carrier frequency and the modulating frequency – also
known as the pulse repetition frequency (PRF) – can be measured,
often without the support of an external arming signal (see below).
Arm
Arming is the general term used for the means to control the actual
start or stop of a measurement. When arming is used, the normal
free-running mode is inhibited, and triggering takes place only
when certain pretrigger conditions are fulfilled.
The signal(s) used for initiating the arming can be applied to three
channels, and the start channel can be different from the stop
channel. All conditions can be set via the menu below.
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