Subject to change without notice
18
NM - AT selection
Press and hold the pushbutton to switch over from auto-
matic to normal triggering (
NM
-LED above the push-
button lit) and vice versa. If the LED is dark, automatic
triggering is selected.
Whether the peak value detection in automatic trigger
mode is automatically activated or not, depends on the
trigger coupling setting (
TRIG.MODE (27)
). The way the
trigger point symbol in the readout responds on different
LEVEL control knob settings indicates the situation:
1.If the trigger symbol can not be shifted in the vertical
direction when no signal is applied or the signal height
is not sufficient, the peak value detection is active.
2.Under the condition that the trigger point symbol
cannot be shifted in such a way that it leaves the signal
display on the screen, the peak value detection is
active.
3.The peak value detection is switched off if the trigger
point can be set outside the maximum peak values of
the signal, thus causing an untriggered signal display.
Slope selection
Briefly pressing this pushbutton selects which slope of
the signal is used for triggering the time base generator.
Each time this pushbutton is briefly pressed, the slope
direction switches from falling edge to rising edge and
vice versa. The current setting is displayed in the readout
by a slope symbol.
AT/NM
and
(SLOPE)
The current time base mode determines the pushbutton
function:
a)
A
time base mode: Both functions affect the
A
time
base only.
b)
alternate
time base mode, with
B
in free run condition:
Both functions affect the
A
time base only.
c)
alternate
time base mode, with
B
in triggered
(DEL.-
TRIG.)
condition:
B
time base
SLOPE
selection only.
d)
B
time base in free run condition: Both functions affect
the - not displayed -
A
time base.
e)
B
time base in triggered
(DEL.TRIG.)
condition:
B
time
base
SLOPE
selection only.
Function settings which are not accessible in the current
operating conditions remain unchanged.
Attention!
In digital mode, the operating conditions described
under item c) are not available.
(17) TR
- Trigger indicator LED
The
TR LED
is lit in
Yt
(time base) mode if the triggering
conditions are met. Whether the LED flashes or is lit
constantly depends on the frequency of the trigger
signal.
(18) LEVEL
– Control knob
Turning the control knob causes a different trigger point
setting (voltage). The trigger unit starts the time base
when the edge of a trigger signal (voltage) crosses the
trigger point. In most
Yt
modes the trigger point is
displayed in the readout by the symbol on the left vertical
graticule line. If the trigger point symbol would overwrite
other readout information or would be invisible when
being set above or below the screen, the symbol
changes and an arrow indicates in which vertical direction
the trigger point has left the screen.
The trigger point symbol is automatically switched off
in those modes where there is no direct relation between
the trigger signal and the displayed signal. The last set-
ting in
A
time base mode is stored and still active if the
alternate (
A and B
) or
B
time base are selected.
This allows for a different level setting for the
B
time
base if the
DEL. TRIG.
function is active. Under this
condition the letter
“B”
is added to the trigger point
symbol.
STORAGE MODE ONLY
In storage mode the trigger point symbol also indicates
the post or pre trigger condition by a horizontal position
shift.
Please note “PTR” (8)
.
(19) X-POS.
– Control knob
This control knob enables an
X
position shift of the
signal(s) in
Yt
and
analog XY
mode. In combination with
X magnification x10 this function makes it possible to
shift any part of the (Yt) signal on the screen.
STORAGE MODE ONLY
In
XY
mode the
X-POS.
knob is inoperative. The
Y-POS.
II
(
15
) knob must be used for X position shift.
(20) X-MAG. x10
– Pushbutton and LED
Each time this pushbutton is pressed the
x10
LED
located above is switched on or off. If the
x10
LED is lit,
the signal display in all Yt and time base modes is
expanded 10 fold and consequently only a tenth part of
the signal curve is visible. The interesting part of the
signal can be made visible with aid of the
X-POS.
control.
As the X expansion results in a higher time base speed
(lower time deflection coefficient), all time and frequency
relevant information in the readout is switched over.
Please note that in alternate time base mode the
intensified sector may become invisible due to the X
position setting.
This pushbutton is not operative in XY mode.
(21) VOLTS/DIV.
– Control knob.
This control knob for
channel I
has a double function.
The following description relates to the input attenuator
function (
VAR
LED dark).
Turning the control knob clockwise increases the
sensitivity in a 1-2-5 sequence and decreases it if turned
Controls and Readout
