43
Subject to change without notice
VOLTS/DIV–SCALE–VAR knob
16
CH1 serves as variable control
that allowes change of the defl ection coeffi cient continuously over
the complete range and consequently the signal display height.
If uncalibrated, a “
>
“ sign is displayed by the readout in front of
the defl ection coeffi cient; if calibrated a “:“ sign. The results of
voltage measurement are labelled in the same way.
After switching over from “Variable on“ to “Variable off“
with the function key, the VOLTS/DIV–SCALE–VAR knob
16
returns to 1-2-5 sequence switching and CH1 to calibrated
condition.
32
VERT/XY
(pushbutton)
This pushbutton switches the ”vertical“ menu on/off. This
menu allows you to select the operating modes of the vertical
amplifiers.
32.1 CH1
If ”CH1“ is selected only CH1 will be turned on, the mode is
Yt. Also the readout will only display the parameters of CH1.
(sensitivity, inverted/not inverted, coupling.) Although CH2 will
not appear in the readout it may be used e.g. as a trigger input.
Its controls are active but are not shown.
32.2 CH2
If ”CH2“ is selected only CH2 will be active, it is Yt mode, and
only its parameters will be shown in the readout. Although CH1
will not appear in the readout it may be used e.g. as a trigger
input. Its controls are active but are not shown.
32.3.1
DUAL trace alt./ chop
In dual trace mode both channels are turned on and the para-
meters of both are shown in the readout. Between the sensi-
tivity indications there is an indication whether alternate ”alt.“
or chopped ”chp“ mode is active. Normally, the mode will be
automatically set by the time base speed selection, but it may
be directly set using the function pushbutton. For time base
speeds of 500 ms/cm to 500 μs/cm, chopped will be used, from
200 μs/cm to 50 ns/cm alternate. This refers to unmagnified time
bases. Alternate is the preferred mode, at any time one channel
is displayed for a full sweep, after each sweep the other channel
has its turn. At slow sweep speeds this will cause annoying
flicker, at still slower ones the channel switching becomes
visible. Here, the chopped mode steps in, both channels are
switched at some high frequency so they are both visible at any
sweep speed. This however, is not appropriate for fast sweep
speeds as the switching may become visible and may interfere
with the proper signal display.
32.3.2
DUAL (digital mode).
In digital mode there is an A/D converter for each channel so
both are measured simultaneously. Hence no channel switching
is necessary and no information pertaining to it is shown.
FFT: DUAL mode will not be offered in combination with FFT.
32.4 ADD
In ADD mode the signals of both channels are algebraically added
and displayed as one sum signal. The Y position can be changed
with both position controls. If one channel is inverted the diffe-
rence will be displayed. Only one ”0 V“ symbol will be shown in the
readout. The ADD mode will be indicated by placing a ”+“ symbol
between the sensitivity indications of both channels.
STOP
In digital mode ”1+2“ will be displayed at the end of
the trace.
Please note that the results of auto and cursor measurements in
this mode will only be correct if the sensitivities of both channels
are identical, otherwise the readout will show ”CH1
<>
CH2“.
As the trigger signals are taken off the inputs and not from the
added signal there is no true reference for the trigger point
symbol, the symbol will thus be switched off in analog mode.
However, the LEVEL A/B control
19
is active. In digital mode a
trigger time symbol is displayed one line above the lowest gra-
ticule line to indicate the trigger time position along the signal
and thus can only be moved horizontally.
FFT: ADD mode will not be offered in combination with FFT.
32.5 XY
In this mode CH1 will move the trace in X direction, hence the
readout will show ”CHX..“, CH2 will move the trace in Y direction,
hence ”CHY...“ will be shown rather than ”CH2...“.
As the time bases are not involved in XY no time base related
information will be shown. Also the trigger circuits are disabled
so no trigger information is shown either. The magnifier MAG
x10
29
is disabled. The ”0-Volt“ symbols will be shown as tri-
angles at the right hand graticule and above the sensitivities.
Both the HORIZONTAL
27
or the POSITION 1
13
knobs will
move the trace horizontally. The Y position is controlled by the
POSITION 2 knob.
32.5.1
Analog mode
The CH1 signal can not be inverted, there is hence no menu
item in the CH1 menu (CH1 VAR pushbutton
31
). The TIME/DIV-
SCALE-VAR knob
28
is disabled.
Please note that the bandwidths and phase differences in XY
analog and digital mode differ considerably so there may be
changes in the signal display when switching the mode.
32.5.2
Digital mode
The readout will indicate the sampling rate with which the A/D
converters digitise the input signals. The appropriate sampling
rate must be set depending on the signals and can be selected
C o n t r o l s a n d R e a d o u t
AUXILIARY INPUT
TRIGGER
EXTERN
Z-INPUT
AUX
1M
Ω
II
15pF
max
100 Vp
INPUTS
1M
Ω
II15pF
max
400 Vp
CAT I
!
CAT I
!
VERT/XY
CH 1
VAR
CH 2
VAR
HOR
VAR
MAG
x10
FFT
CH 1
CH 2
X-INP
POWER
43
31
34
32
33
35
36
37
38
29
30
