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Subject to change without notice

pushbutton is illuminated. The length of the intensiﬁed sector

is determined by the speed of time base B and is equal to the
run time of B. Hence this intensiﬁed portion of A will be spread
over the full screen as displayed by B and thus expanded. The
Y position of the signal is the same when displayed with either
A or B. This means, however, that both displays will be written
over each other.

This can be avoided by changing the time base B trace position in
the following way: Press the CH1/2–CURSOR–MA/REF–ZOOM-
pushbutton

to call the “Pos./Scale“ menu. Then press the

function key “TB B“ so that the POSITION 1 knob

becomes

the trace separation control (see 13.1.5 Y Position - 2nd time
base). As there is only a demand for trace separation in “Search
mode“ this function is only offered in this time base mode.

Also in ”Search“ the 10 x magniﬁer is available by pressing the
pushbutton MAG x10

. The magniﬁer will affect solely time

base B.

30.1.3

”B only“

In this mode only time base B will be displayed. Thus the readout
only displays in the top left position only “B“. The TIME/DIV-SCA-
LE-VAR knob then only affects time base B. By aid of the MAG
x10 pushbutton

the signal display can be expanded 10 fold;

reducing the time deﬂ ection coefﬁ cient by factor 10.

30.1.4

B trigger –

Edge

In this mode time base B will not start immediately after the set
delay time has elapsed, but will be only set ready, waiting for a
signal trigger. This has the advantage that any jitter is removed,
but the delay time adjustment will now only have the effect that
the time base B display will jump from signal period to period.
In this setting a positive slope will trigger.

The (trigger) LEVEL A/B

knob will set the trigger level for

B. Only normal triggering and DC coupling are possible. All
parameters of time base A remain stored and preserved. (LE-
VEL, auto or normal, Slope, coupling). In addition to the delay
time (”Dt:...“) also the B trigger parameters are shown in the
readout: ”BTr:slope, DC“. In ”Search“ mode the trigger point
symbol will be preceded by ”B“. As mentioned changing the
delay time will not cause a continuous move of the intensiﬁed
portion of the time base A display and the time base B display,
but jumps from signal period to period.

If the trigger level symbol of time base B is shifted outside the
signal representation by time base A there will be no triggering
of time base B any more and thus no time base B display. The
same holds in time base B only mode.

30.1.5

B trigger –

Edge

Except for the negative edge the function is identical to the one
described above (30.1.4).

30.1.6

B trigger – OFF

Time base B will be started at the end of the delay time set.
The delay time can be changed continuously in this mode and
can be seen as the intensiﬁed sector of the time base A display.
The disadvantage here is that with very long delay times, jitter
of the time base B display may occur. As time base B is not
operated in the signal triggered mode, the controls for time
base B trigger will be disabled.

30.1.7

A variable – On Off

If ”On“ was selected the TIME/DIV-SCALE-VAR knob

will

function as variable control for the time base A speed. Only
in time base A only mode will this option be available in the
menu.
For a full description see ”28.1.3 Variable“.

30.1.8

B variable – On Off

If ”On“ was selected the TIME/DIV-SCALE-VAR knob

will

function as the time base B variable control. For a full descrip-
tion see ”28.1.3 Variable“.

30.1.9

Holdoff …%

In this mode the hold off time may be selected from 0 to
100 % with the INTENS knob

. Values

0 extend the

waiting time after a sweep before a new one can start
and decrease thus the repetition rate which may darken
the display. This is indicated by the HOLD OFF-LED

lighting up. The hold off time is only valid for time base A.
Further information can be found in the section ”Hold off adjust-
ment“ in the chapter ”Triggering and time bases“.

30.2. Digital mode

In the ”Zoom“ menu the following time base functions are
available:

30.2.1

Off

In ”Zoom Off“ condition only time base A is active. The readout
will thus only show ”A...“ in the top left corner. The speed can
be set with the TIME/DIV-SCALE-VAR knob

30.2.2

Part of the time base A display will be intensiﬁed and this portion
will also be displayed expanded over the full screen, if neither
reference nor mathematic signal display is activated. With the
HORIZONTAL knob

the intensiﬁed sector and the expanded

display can be shifted provided that the pushbutton X POS DE-

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