22
Horizontal System
also allow you to center the markers in the middle of
the screen. This feature enables you to quickly compare
marked signal sections in ZOOM mode. To delete a marker,
center it in the middle of the screen and press the SET/CLR
key once again. You can also delete all time markers simul-
taneously in the marker soft menu. With the soft menu
key TRIGGER TIME TO ZERO the triger time can be set to
0 s. Additionally, CLEAR ALL MARKER removes all defined
time stamp markers.
Fig. 5.6: Marker in Zoom mode
6 Trigger System
Four keys are available to se-
lect one of the frequently used
trigger settings:
❙
TYPE
: Selection of trigger
type Edge, Puls, Logic, Video
and Hold off time
❙
SLOPE
: Type of slope
❙
SOURCE: Determines the
trigger source
❙
FILTER
: Determines the
exact trigger conditions
Additional keys are available
to select the trigger mo-
des (AUTO, NORMAL and
SINGLE).
6 .1 Trigger Modes Auto, Normal and Single
The AUTO/NORM
29
key allows you to toggle directly
between the basic trigger modes. If Auto mode is activa-
ted, the key is not illuminated. Pressing the key will activate
NORMAL mode, and a red LED will highlight the
key. In AUTO mode, the screen always displays a signal.
If a signal fulfills the
trigger conditions, the oscilloscope
will synchronize with this event and triggers when the set
condition is met. In case of a signal that does not fulfill the
trigger condition (a simple case would be direct current),
the oscilloscope itself will generate a trigger event. This
allows a glance at the input signals at any time, regardless
of the trigger condition. In NORMAL mode, the signal will
now be captured and displayed if the trigger condition is
met. In case no new signal fulfills the set trigger condition,
the signal that was triggered last will be displayed. To
ensure that only a signal that meets the trigger condition
is detected and displayed, press the Single key to
33
ac-
tivate this mode. This key is highlighted in white when
the SINGLE mode is activated. The R&S®HMO1002 resp.
R&S®HMO1202 series detection and trigger system is now
activated, indicated by a blinking RUN/STOP key
39
. If the
trigger condition is fulfilled, the trigger system is activated,
data is stored and the oscilloscope switches to STOP mode
(the RUN/STOP key is permanently highlighted in red).
6 .2 Trigger Source
The two analog channels are available as trigger sources
(SOURCE key). If the optional extension with active logic
probes R&S®HO3508 including 8 digital inputs is connec-
ted, up to 8 digital inputs are available as trigger source.
The soft menu key AC LINE enables you to trigger the
trigger at system frequency. The trigger signal is extracted
internally from the power supply.
6 .3 Trigger type
The trigger type can be selected with the TYPE key
17
in
the TRIGGER section. A submenu will be opened.
Fig. 6.1: Control panel
for the trigger system
28
C
29
30
33
31
34
35
36
32
