39
Subject to change without notice
26.2.2
DELAY Zoom Pos
This pushbutton will be illuminated if the ”Time base“ menu was
called with the HOR VAR pushbutton
30
and ”Search“ selected.
The HORIZONTAL
27
knob can then be used to select a portion
of the time base display which is to be displayed expanded in
time.
In ”Search“ mode the normal and the expanded displays are
displayed simultaneously, if neither reference nor mathematic
signals are displayed. The expanded portion of the signal will
be shown on the normal display as an intensified sector. The
length of this sector is dependent upon the setting of the 2nd
”Z“, time base which is shown in the readout as ”Z...“ and is
equal to the run time of the Z time base.
27
HORIZONTAL
(knob)
The various functions of this knob depend on the operating mode
and are described under X POS DELAY pushbutton
26
.
FFT (digital mode only)
As in Yt mode this knob moves the display in X direction. This
changes the frequency range and consequently the center
frequency setting displayed in the readout.
28
TIME/DIV.–SCALE–VAR
(knob)
This knob is normally used as the time base speed selector, but
has also other functions depending on the operating mode. In
XY mode this control is disabled.
28.1 Analog mode
28.1.1
Time base A time/cm selection
This function is active if in the ”Time base“ menu HOR VAR
pushbutton
30
”A only“ is selected and the option ”A variable
On Off“ is set to Off.
Turning the knob CCW will decrease, turning it CW will increa-
se the time base speed. The time base speed may be chosen
between 500 ms/cm... 50 ns/cm in a 1-2-5 sequence and will be
calibrated. The readout will show the setting (e.g. ”A:50ns“).
28.1.2
Time base B time/cm selection
This function is active if in the ”Time base“ menu HOR VAR
pushbutton
30
”Search“ or ”B only“ was selected and the option
”B variable On Off“ was set to Off. Turning the control CCW will
decrease, turning it CW will increase the time base speed. The
speed can be selected between 20 ms/cm.. 50 ns/cm in a 1-2-5
sequence and will be calibrated. The readout will show the speed
(e.g. ”B:50ns“). The time base B allows display of portions of
the time base A display on an expanded time base scale. This
implies that the speed of TB B must always be greater than that
of TB A. Therefore with the exception of 50 ns/cm, TB B can not
be set to the same speed as TB A or slower.
Further information is available in the section ”Time base B (2
nd
time base) / Delay / Triggering“ (Analog mode) in the chapter
”Triggering and time bases“.
28.1.3
Variable
The TIME/DIV–SCALE–VAR control may also be used to change
the time base speed continuously but uncalibrated. VAR will
light up on top of the HOR VAR pushbutton
30
in order to warn
that the time base is uncalibrated and the knob has now that
function.
In order to arrive at that function press HOR VAR pushbutton
30
which calls the ”Time base“ menu. Depending whether time
base A or B is selected either ”A variable On Off“ or ”B variable
On Off“ will be shown. The function pushbutton can then be
used to select On/Off.
In order to point out that the time base is now uncalibrated
the readout will replace ”:“ by ”
>
“ preceding the time/cm. (e.g.
”A
>
500ns“ and ”B
>
200ns“). Also the results of cursor time/pe-
riod measurements will be marked that way.
28.2 Yt digital mode
28.2.1
ZOOM OFF (A time base time/cm selection)
Select the menu ”Zoom“ by pressing HOR VAR pushbutton
30
and then ”Off“ in order to set the function of the knob TIME/
DIV–SCALE–VAR to time base A speed as in analog mode. If
”Zoom Off“ is active, the whole memory will always be displayed.
Turning the control CCW will decrease and turning it CW will
increase the time base speed. Depending on the signal captu-
re/display the time base can be set from 50 s/cm to 5 ns/cm in
a 1-2-5 sequence (e.g. ”A:50ns“) and will be calibrated. There
is no variable function as in analog mode.
28.2.2
Search Zoom only (Zoom time base speed selection)
One of the functions ”Search“ or ”Zoom only“ may be selected
in the ”Zoom“ menu after pressing HOR VAR pushbutton
30
.
”Zoom Off“ is equivalent to time base A in analog mode. With
”Zoom only“ a portion of the display in Zoom ”Off“ can be ex-
panded over the whole screen. This is possible because there
is a very large memory for signal capture/display. The ”Zoom
Off“ display will present the whole memory contents. With
”Search“ both the ”Zoom Off“ and the expanded ”Zoom only“
C o n t r o l s a n d R e a d o u t
FFT-
Marker
VOLTS / DIV
SCALE
·
VAR
VOLTS / DIV
SCALE
·
VAR
TIME / DIV
SCALE
·
VAR
AUTO
MEASURE
20 V
1 mV
20 V
1 mV
X-POS
LEVEL A/B
50s
5ns
AUX
HORIZONTAL
DELAY
CH 1/2
CURSOR
MA/REF
ZOOM
MODE
FILTER
SOURCE
TRIG
’
d
NORM
HOLD OFF
TRIGGER
POSITION 1
POSITION 2
VERT/XY
CH 1
VAR
CH 2
VAR
HOR
VAR
MAG
x10
FFT
POWER
19
26
27
20
23
21
24
28
22
25
29
30
13
15
14
17
16
18
