User manual

23
Horizontal System
5.7 Marker Function
Markersallowyoutohighlightspecicpositionsonthe
screen, e.g. a rising or falling slope, an unexpected sig-
nal value or a search result. Markers can be used to iden-
tifyspecicsignalsectionstozoominonandtoanalyze
the data more closely. Use the soft menu to activate the
marker function. Press the MENU key in the HORIZON-
TAL section to open the soft menu. Use the universal knob
in the menu to select MARKER. Once this mode is acti-
vated, you can press the SET/CLR key to set a time mar-
ker at the 6th time unit (the menu in the center of the grid
must be deactivated). The time markers are marked by a
vertical line in gray-blue. The knob X Position allows you to
move the signal including the set marker. After identifying
an important signal position and setting it to the center of
the screen using the position knob, you can set an additi-
onal marker. This procedure allows you to mark up to 8 in-
teresting positions within the signal. You can toggle bet-
ween markers by pressing the arrow keys
37
. These
keys 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dened
time stamp markers.
5.8 Search Function
The search function of the R&S®HMO Compact series ena-
bles you to search for all slopes, pulse widths, peaks or ad-
ditional events in the detection mode that match the ma-
nuallyspeciedsearchcriteria.Specicsettingsareavaila-
ble for each search type. Searches can be performed on
any analog channel or mathematical signal. The searched
timebasesectioncanberestrictedbydeningalevel.
Press the MENU key in the HORIZONTAL section of the
control panel to activate the search function in the soft
menu. Use the universal knob in the CURSOR/MENU sec-
tion to select the menu item SEARCH. Once this mode
Fig. 5.6: Marker in zoom mode
isactivated,youcandeneevents,e.g.arise time with
specicattributes.Thesearchfunctionwillcheckthese
events in STOP mode. Press the menu item SEARCH TYPE
and use the universal knob in the CURSOR/MENU section
to select the desired search criteria. The following func-
tions are available:
❙ Slope: Comparable to the slope trigger; this function
searches for slopes in the signal. The point in time of a
detected slope corresponds to the point in time when the
signal leaves the set hysteresis. The soft key LEVEL
selects a level for the slope detection of the search
function. The search function level matches the trigger
level of the slope trigger, for instance. Level and hysteresis
will display in the signal window. The hysteresis
determines the area that the signal has to pass until a
validslopeisdetected.Thisareaalsodenestherise time
oftheslope.Itisrecommendedtoselectasufciently
large hysteresis to reduce noise on the signal slope.
❙ Pulse: Comparable to the pulse width trigger; this function
searches for pulses with a predetermined pulse width. A
pulse always consists of a rising and a falling slope.
Leaving the hysteresisdenesthestartandendtimeofthe
pulse. The level for the search function corresponds to the
trigger level of the slope trigger, for instance. Level and
hysteresis will display in the signal window. The adjustable
comparison type is a search criterium for the detected time
event width. The pulse width is the time period between
start and stop slope of the pulse.
❙ Peak: The peak search function searches for pulses
within the signal. The time of the event is the maximum
value of the peak.
❙ Rise time / fall time: This function searches for slopes
withaspecicrise/fall time within the signal. The point in
time of a detected slope corresponds to the point in time
when the signal leaves the set hysteresis. The upper and
lowerleveldenetheupper/lowerpositionofthe
hysteresis. The adjusted level will display in the signal
window. The adjustable comparison type is a search
criterium for the detected time event width.
❙ Runt: A runt is an aborted pulse within a signal. This
occurs when the rise times of the system are greater than
necessary for the desired pulse width. A positive runt
exceeds the lower level of the hysteresis, for instance, but
does not reach the upper level. The analyzing digital
circuits of this signal fail to detect the pulse which leads to
transmission errors. The pulse width of the runtisdened
by the entry and exit point from the hysteresis (duration
between start and stop slope of the pulse). The adjustable
comparison type is a search criterium for the detected
timeeventwidth.Thedifferencedenesthemaximum
timerangebywhichthespeciedeventwidthmayvary.
Once you have selected the appropriate search type, you
can choose the desired SOURCE (choose from any of the
activated analog channels including mathematical chan-
nels). Use the menu item SETUP to open a submenu
where you can choose the settings for the selected search
criterium(e.g.greaterthanaspecicpulse width). Some
of the adjustable parameters may be dependent on the