31
Subject to change without notice
D i s p l a y o f s i g n a l s
tion mode in case of a non-triggered condition over an extended
period of time. This acquisition mode does not display an info
window as the data currently captured is displayed.
AUX. CURSORS:
This soft menu allows you to define the settings for auxiliary
cursors. Pressing the function keys enables you to activate or
deactivate the cursors. The menu item DEFAULTS resets the
default settings.
7.2 Use of the virtual screen area
The graticule for the HMO series includes 8 vertical divisions but
also has a virtual range of 20 divisions. These 20 divisions may
be used entirely by the optional digital channels D0 to D15, the
mathematical channels and the references signals. The analog
channels may use up to ±5 divisions from the center.
Fig. 7.1: Drawing of the virtual screen area and an example
Fig. 7.1 illustrates the functionality of the virtual screen. The
display includes a section of 8 vertical divisions in gray. This
section enables you to display analog signals. The small bar
next to the graticule indicates the position of the 8 visible divi
-
sions within the available 20 divisions. By pressing the SCROLL
BAR
5
the bar will be activated and displayed in blue and you
can use the universal knob to shift the 8 visible divisions (gray
section) within the available 20 divisions. This allows a simple
and clear display of many individual signal portions.
7.3 Signal
intensity and persistence functions
In the standard mode, the key INTENS/PERSIST will light up
white: the intensity of the signal display can be changed with
the universal knob from 0 to 100 %. The persistence mode may
be selected for the display of varying signals: this is a storage
mode such that several curves may be written to remain on
the screen. Also the so called „Variable Persistence“ may be
selected: in this mode the persistence can be changed from
50 ms to infinity; this will cause the most recent portion of the
signal to appear bright while the preceeding portions will fade
in proportion to the time elapsed. This mode can be selected in
the soft menu which will open upon pushing the key INTENS/
PERSIST; the signal intensity can be changed also in this menu.
Two more menu items are available:
GRID
and
BACKLIGHT
by
pushing the respective soft menu keys; the intensities can be
changed with the universal knob. The soft menu key next to
the lowest menu item toggles between
HIGH
and
LOW
of the
LED’s of all backlit keys and all other LED displays on the
front panel.
Fig. 7.2: Menu for setting the signal display intensities
After selecting the menu items PERSISTENCE and ADJUST
the persistence function can be defined: there are 3 choices
for the duration of the persistence: OFF, AUTOMATIC and
MANUAL. In MANUAL operation, the duration can be changed
with the
universal knob from 50 ms to infinity. If a finite time
was selected, the signal periods will be written on top of each
other such that the brightness will diminish from recent to
oldest. If e.g. 300 ms is selected, the signal curves will be-
come darker in 50ms steps and erased after 300 ms. In this
soft menu the function BACKGROUND may be activated in
addition: then all signal curves ever displayed will be shown
in the darkest colour.
Fig. 7.3: Persistence function
This kind of display is for example very useful for the analysis
of extreme values of different signals.
7.4 XY display
The HMO series features a key that allows you to switch directly
to the XY display. Two signals will be displayed simultaneously,
one in Y direction and one in X direction. This implicates that the
time base X will be replaced by amplitude values of a second
-
source. The resulting signal curves for harmonic signals are
known as Lissajous figures and allow the analysis of
frequency
and phase position for these two signals. In case of a nearly iden
-
tical
frequency the figure will rotate. If the
frequency is exactly
identical, the figure will stand still and the phase position can
be deduced from its shape. You can activate the XY display by
