27
Subject to change without notice
C o n t r o l s a n d R e a d o u t
– When measuring pulse signals there may be an infl uence
of the duty cycle or the slope selected on the accuracy of
the result.
– The signal must remain within the graticule area, i.e. the
input amplifi ers must not be overdriven.
– On condition the variable function is switched on the … VAR
pushbutton is lit, the defl ection coeffi cient and/or the time
base are/is uncalibrated and a “
>
“ sign is displayed by the
readout in front of the defl ection coeffi cient. The results of
voltage and/or time/frequency measurement are labelled
in the same way.
STOP
Please note:
Complex signals should be measured using the
CURSORs.
If a variable is activated and thus the sensitivity or time base
uncalibrated, the ”:“ will be replaced by a ”
>
“ symbol.
14.1 Meas.(uring) Type
If this function is activated, the INTENS knob
2
can be used
for measurement selection. In most cases the corresponding
unit will be automatically displayed. The measuring modes are
self explanatory.
14.2 Respect Tr
The “Respect Tr” display is just a reminder indicating that the
trigger signal is used for measurement. The assigned function
key has no effect.
14.3 Off
Pressing the function key “Off” switches the “AUTO MEASURE”
menu and the measurement result line off.
If only the displayed “AUTO MEASURE” menu is to be switched
off, press the MENU OFF pushbutton
37
.
15
LEVEL A/B
(knob)
The LEVEL control allows to set the trigger level, i.e. the vol-
tage respectively signal level, which will generate a trigger to
start the time base whenever the signal passes that level. In
most Yt- modes the readout will show a symbol the vertical
position of which indicates the signal point which will trigger.
The trigger symbol will not be shown those modes where
there is no direct relationship between trigger signal and
trigger point.
In normal trigger mode the LEVEL control will move the trigger
symbol anywhere. In automatic peak-to-peak detection mode the
level can only be selected between the signal’s peak values.
The movement of the trigger symbol is vertical only. The range
of this symbol is limited in order to prevent that this symbol will
overwrite other readout information. As soon as the trigger sym-
bol leaves the graticule its form will change, this change signals
in which direction the trigger symbol left the graticule.
Depending on the time base mode the LEVEL control will affect
the time base A or B triggering. Press the HOR VAR pushbutton
26
in order to select the time base mode in the ”Time base“ menu. In
”Search“ mode (alternate time base mode) the last trigger level
setting for time base A will remain valid (graticule left) if time
base B is switched to triggered mode. (Menu ”Time base“: set
B trigger to positive or negative slope). Thereafter the LEVEL
A/B control will control the time base B trigger, a second trigger
point symbol will be shown and marked with ”B“.
turning it CW will increase the sensitivity. The sensitivities can
be selected from 1 mV/cm to 5 V/cm in a 1-2-5 sequence; the
range is (automatic probe) factor or (manual probe setting) de-
pendent. The readout will show the sensitivity (e.g. ”CH2:5mV..“).
Depending on the sensitivity the signal will be displayed with
smaller or greater amplitude.
STOP
Please note:
This sensitivity selection is always active, e.g. also,
if CH1 only was chosen. In that case CH2 may be
used as trigger source.
13.2 Variable control
Select this function with the CH2 VAR pushbutton
29
to display
the “CH2” menu and press the function key “Variable On Off”
so that “On” is activated. The CH2 VAR pushbutton will light up,
indicating that the VOLTS/DIV VAR knob
13
now has the function
of a variable control. Using the VOLTS/DIV VAR control knob the
sensitivity can be changed from 1 mV/cm to
>
20 V/cm; the range
is (automatic probe) factor or (manual probe setting) dependent
and thus the signal display height.
Uncalibrated the readout will add a ”
>
“ to the sensitivity in-
dication (”CH2
>
5mV..“) in order to show that the sensitivity is
now uncalibrated. The results of cursor measurements will be
fl agged accordingly.
After resetting “Variable” to “Off”, the CH2 VAR pushbutton
29
extinguish, the defl ection coeffi cient is calibrated and the
VOLTS/DIV-VAR knob
13
switches in 1-2-5 sequence.
14
AUTO MEASURE
(pushbutton)
In XY mode AUTO MEASURE can not be called.
If the AUTO MEASURE function is switched off, pressing this
pushbuttones it on and displays the measuring results in the
readout (2
nd
line in the top right position), (e.g. dc(Tr):100μV.)
Symbol (Tr) indicates reference to the trigger signal. Someti-
mes a ”?“ will be displayed, indicating that there is no, or an
insuffi cient signal.
If AUTO MEASURE is activated, pressing the AUTO MEASURE
pushbutton again causes the display of the “Measure” menu
and its selection box. Additionally the FOCUS TRACE MENU
pushbutton
3
is lit, indicating that the INTENS knob
2
can be
used to select the measurement mode.
Depending on the operating mode this menu offers various
automatic measurements of the trigger signal. The following
conditions must be met:
a) For frequency or period measurements suffi cient trigger
signals must be available. Use normal triggering for signals
<
20 Hz. Please note that signals of very low frequency may
require seconds to complete one measurement.
b) In order to measure DC or the DC content of a signal the
input channel as well as the trigger must be set to DC coup-
ling.
Further notes:
– Due to the limited frequency response of the trigger channel
the accuracy will decrease with increasing frequency.
– The frequency responses of the vertical channel and the
trigger channel differ substantially; this may affect the signal
display.
– When measuring very low frequency signals the display will
follow the signal.
