User manual
23
Horizontal System
5.4 Interlace Mode
In interlace mode, ADC and storage of two channels are
connected. This doubles the sampling rate and the acqui-
sition memory. Interlace groups are channels 1 and 2 and
channels 3 and 4. If an interlace group is not interlace-ca-
pable, the non-interlace mode is also applied to the related
group. A channel is considered active even if it has been
deactivated while still serving as the trigger source. If a
channel is activated, the respective LED next to the input
connector is illuminated. The following conditions must be
met to activate the Interlace mode:
❙ No active logic pod
❙ None of the serial or parallel buses are active
❙ Logic trigger not active
The interlace mode will be activated automatically. The fol-
lowingtableshowsthechannelcongurationsthatallow
the operation in interlace mode.
Interlace group 1 Interlace group 2
CH1 CH2 CH3 CH4
ON Off Off Off
Off ON Off Off
Off Off ON Off
Off Off Off ON
ON Off ON Off
Off ON ON Off
Off ON Off ON
Tab.5.2:Channelcongurationininterlace mode
5.5 ZOOM function
The R&S®HMO Compact series features a memory depth
of 1 MByte per channel. This allows the user to record long
and complex signals which can be analyzed in full detail
with the Zoom function. To activate this feature, press the
ZOOM key
40
. The screen will be divided into two sections.
The upper window displays the entire time base window
whereas the lower graticule shows an enlarged section of
the upper window. The enlarged signal section is marked
by two blue cursors in the original signal (upper window).
If several channels are activated in Zoom mode, all dis-
played channels will be zoomed simultaneously by the
same factor and at the identical position. Fig. 5.5 displays
the Zoom window with 100 µs per division. The signal was
captured within a time window of 12ms. The zoom area
(lower grid) also displays the parameter for zoom time base
whereas time is displayed above the zoom window. Z in-
dicates the zoom time base (zoom factor) and determines
the width of the zoom area displayed in the zoom window
(10 divisions x scaling per division). Tz indicates the zoom
time and determines the position of the zoom area. The
time base setting in the upper right of the display is high-
lighted in gray while the zoom time base above the zoom
window is marked in white. The large knob in the HORI-
ZONTAL menu is used to change the zoom factor. You can
also press this knob. If the knob is pushed, the time base
setting is highlighted in white and the zoom time base in
gray. Now the knob is available to select the time base set-
ting. This allows you to change time base settings without
having to leave the zoom mode. Pressing the knob again
will highlight the cursors limiting the zoom area in white,
allowing you to use the knob to change the zoom area.
Now you can use the small knob in the horizontal area of
the control panel to move the position of the zoomed sec-
tion across the entire signal. As described above, pressing
the large knob enables you to set the time base but not the
zoom factor. This in turn enables the small knob to move
thetriggerpositiontodenetherelationshipofpre-and
post captures/records.
In the acquisition mode ROLL, it is generally not possible
to zoom in on the memory because the signal values of
the X axis are always captured with the maximum memory
depth. The acquisition mode NORMAL always includes
more samples in the memory than what can be shown in
the display. That explains why in this mode you are able
to zoom in on the memory. The same does not apply to
the values in the Y axis (amplitude). These values apply to
aspeciedaxisandcanthereforealsobescaledinROLL
mode.
5.6 Navigation function
The X-POS. function (MENU key in the HORIZONTAL
section) offers easy trigger time handling and allows it
to be entered numerically. The soft menu keys allow you
to set the trigger time to the minimum or the maximum
value, for instance. You can use the soft menu key TIME
REFERENCEtodenewhereinthesignalwindowtond
the trigger point value “0”. The signal is scaled by this re-
ference point. You can use the universal knob in the CUR-
SOR/MENU section to select the desired setting.
5.7 Marker function
Markersallowyoutohighlightspecicpositionsonthe
screen, e.g. a rising or falling slope, an unexpected signal
value or a search result. Markers can be used to identify
specicsignalsectionstozoominonandtoanalyzethe
data more closely. Use the soft menu to activate the mar-
ker function. Press the MENU key in the HORIZONTAL
The ZOOM function is not available in ROLL mode.
Fig. 5.5: Zoom function