34
Subject to change without notice
STOP
Note:
The function Cur. Track (cursor tracking) is only
available if 2 cursors are on display. The cursors
will then be moved simultaneously (tracking)
without changing their respective positions.
15
CH1/2–CURSOR–MA/REF–ZOOM
(pushbutton)
The function of the POSITION 1, POSITION 2 and VOLTS/DIV kn-
obs can be selected if suitable operating conditions are present
(cursor measurement, mathematic signal- and reference signal
display, ZOOM- and time base Search function). Then a menu
will be called by pressing this pushbutton and it will light.
The pushbutton will signal the function activated corresponding
to the front panel labelling:
dark:
Y position and vertical sensitivity CH1 and CH2.
blue:
Y position of cursors.
green: Y position and display height of:
– Mathematics signal(s)
– Reference signal(s)
– ZOOM or time base B display of signal(s)
16
VOLTS/DIV–SCALE–VAR
(knob)
This knob is a multi function CH1 control.
16.1 Selection of vertical sensitivity (1-2-5 sequence)
This function is present if the CH1 VAR button
31
is not lit.
Provided VAR on pushbutton CH1 is not illuminated the sensitivity
will be calibrated. Turning the control CCW will decrease and
turning it CW will increase the sensitivity. 1 mV/cm to 20 V/cm
can be selected in a 1-2-5 sequence. The readout will display
the calibrated sensitivity (e.g. ”CH1: 5mV..“). Depending on the
sensitivity selection, the signal will be shown with smaller or
greater amplitude.
STOP
Please note:
This sensitivity selection is always active, e.g. also,
if CH2 only was chosen. In that case CH1 may be
used as trigger source.
16.2 Variable control
This function can be activated by pressing the CH1 VAR push-
button
31
and selecting On by the “Variable“ function key. The
CH1 VAR pushbutton
31
lights and indicates that the VOLTS/DIV–
SCALE–VAR knob
16
now serves as Variable control. Thereafter
the defl ection coeffi cient can be changed continuously between
1 mV/cm and
>
20 V/cm and thus the signal display height.
If uncalibrated, the defl ection coeffi cient will be displayed as
e.g. “...
>
5mV...“ and correspondingly the results of cursor
voltage measurement. In calibrated condition e.g. “...:5mV...“
will be displayed.
If variable “off“ is activated in the CH1 menu, the defl ection
coeffi cient becomes calibrated, the CH1 VAR pushbutton
31
does not light any longer and the VOLTS/DIV–SCALE–VAR knob
16
returns to 1-2-5 sequence.
16.3 Scaling the FFT display
(digital mode only)
16.3.1
Preliminary note:
To avoid erroneous spectrum displays, it must be checked be-
fore switching over to FFT, that the Yt (time base) signal display
is suitable for calculation in FFT. This means that the time base
setting (sampling rate) must enable the display of minimum one
signal period; in the case of complex signals this is regarding
the signal with the lowest frequency. On the other hand the
sampling rate must not be too low (too many signal periods)
to avoid so called aliasing. The signal display height should be
between 5 mm (0.5 div.) and 8 cm (8 div.). Signal display heights
>
8 cm, cause the danger that the dynamic range is exceeded, so
that signals deformed by limiting effects to square wave form,
become digitised and at least show spectrum displays spectra
that do not exist in reality. If the sampling rate is too low the
readout displays “ALS“; if the signal is too high “overrange ±“
will be displayed.
Such problems can be avoided, by pressing the AUTOSET push-
button
11
before switching over to FFT or during FFT mode.
16.4.2
Scaling
In FFT mode the VOLTS/DIV–SCALE–VAR knob
16
only chan-
ges the scaling of the spectrum display; this means that the
spectrum (including noise) is displayed in double height after
switching over from 20dB/cm to 10dB/cm. The Y defl ection coef-
fi cient previously selected in Yt mode is thereby not affected.
If dBV is set in the FFT menu, the scaling is switched over from
5 dB/cm to 500 dB/cm in 1-2-5 sequence by the VOLTS/DIV–SCA-
LE–VAR knob
16
; at V
(rms)
the range is from 10 μV/cm to 20 V/cm
also switched in 1-2-5 sequence. Please note that in contrast
to Yt and XY signal display modes, rms values are displayed,
not peak to peak values.
17
VOLTS/DIV–SCALE–VAR
(knob)
This multi function control belongs to CH2.
17.1 Selection of vertical sensitivity
(1-2-5 sequence)
This function is present if the CH2 VAR-pushbutton
33
is not
lit.
The sensitivity will be calibrated provided VAR on the CH2 push-
button is not illuminated. Turning the control CCW will decrease,
turning it CW will increase the sensitivity. The sensitivities can
be selected from 1 mV/cm to 20 V/cm in a 1-2-5 sequence. 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: The sensitivity control is always active,
i.e. also if CH2 is not selected. CH2 may then still be
used e.g. as a trigger source.
17.2 Variable control
This function can be activated by pressing the CH2 VAR push-
button
33
and selecting On by the “Variable“ function key. The
CH2 VAR pushbutton
33
lights and indicates that the VOLTS/DIV–
SCALE–VAR knob
17
now serves as Variable control. Thereafter
the defl ection coeffi cient can be changed continuously between
1 mV/cm and
>
20 V/cm and thus the signal display height.
If uncalibrated, the defl ection coeffi cient will be displayed as
e.g. “...
>
5mV...“ and correspondingly the results of cursor
voltage measurement. In calibrated condition e.g. “...:5mV...“
will be displayed.
If variable “off“ is activated in the CH2 menu, the defl ection
coeffi cient becomes calibrated, the CH2 VAR pushbutton
33
does not light any longer and the VOLTS/DIV–SCALE–VAR knob
17
returns to 1-2-5 sequence.
17.3 Scaling the FFT display
(digital mode only)
17.3.1
Preliminary note:
To avoid erroneous spectrum displays, it must be checked be-
fore switching over to FFT, that the Yt (time base) signal display
is suitable for calculation in FFT. This means that the time base
C o n t r o l s a n d R e a d o u t
