17
Subject to change without notice
“ext”:
External trigger mode is available in all time base and trigger
coupling modes except line/mains triggering. Then the
TRIG.EXT
. (30) BNC socket serves as the external trigger
signal input. On external triggering mode, the intensity
modulation (Z), which might have been present before, is
automatically switched off.
Note: The trigger point symbol is always switched
off if external triggering is chosen.
STORAGE MODE ONLY.
In
“rol”
(ROLL) mode all trigger controls and readout
information are deactivated.
(18) VOLTS/DIV.
Control knob for channel II with a double
function.
This control is active only if channel II is enabled and it‘s
input coupling (AC or DC) is activated. Channel II is active
in CH II (Mono), DUAL, Addition (“add”) and XY mode. The
knob is automatically disabled if the channel related to it is
switched off, or if the input coupling is set to GND (ground).
Y deflection coefficient setting (input attenuator):
This function is available if the VAR. LED is dark.
Turning the control knob clockwise increases the sensitivity
(decreases the deflection coefficient) in a 1-2-5 sequence
and decreases the sensitivity (increases the deflection
coefficient) if turned in the opposite direction (ccw.). The
available range is from 1mV/div up to 20V/div.
The deflection coefficients and additional information
regarding the active channel(s) are displayed in the readout,
e.g.
”Y2:
deflection coefficient, input coupling”
. The ”:”
:”
:”
:”
:”
symbolizes calibrated measuring conditions and is replaced
by the
”
”
”
”
”
>
”
”
”
”
”
symbol in uncalibrated conditions.
VAR.:
The vernier (variable) function is described under item VAR (19).
(19) CH II - VAR
.
.
.
.
. Pushbutton with several functions.
Pressing and holding this pushbutton selects the
VOLTS/
DIV
. (18)
. (18)
. (18)
. (18)
. (18) control knob function between attenuator and
vernier (variable). The current setting is displayed by the
VAR-LED
located above the knob.
CH II mode:
Briefly pressing the CHII button sets the instrument to
channel II (
Mono CH II
) mode. The deflection coefficient
displayed in the readout indicates the current conditions
(
”Y2...”
). If neither external nor line (mains) triggering was
Controls and readout
active, the internal trigger source automatically switches
over to channel II and the READOUT displays “Y2, trigger
slope, trigger coupling”. The last function setting of the
VOLTS/DIV (18
)
)
)
)
) knob remains unchanged.
All channel II related controls are active if the
input (28)
is
not set to
GND (29)
.
VAR.:
After switching the
VAR-LED (18)
on, the deflection
coefficient is still calibrated. Turning the
VOLTS/DIV. (18)
control knob counter clockwise reduces the signal height
and the deflection coefficient becomes uncalibrated.
The readout then displays e.g.
”Y2>...”
indicating the
uncalibrated condition instead of
”Y2:...”
. Pressing and
holding the CHI pushbutton again switches the LED off,
sets the deflection coefficient into calibrated condition
and activates the attenuator function. The previous vernier
setting will not be stored.
INV.:
Briefly and simultaneously pressing the CHII and the DUAL-
MENU (16) pushbutton switches the channel II invert
function on or off. The invert ”on” condition is indicated
on the readout by a horizontal bar above
“Y2”
(Yt mode)
respectively
“Y”
(XY mode). The invert function causes
the signal display of channel II to be inverted by 180°.
(20) TRIG. MODE
Pushbuttons.
Pressing one of these pushbuttons opens the trigger
coupling pulldown menu with the actual setting highlighted.
Briefly pressing a pushbutton selects the trigger coupling.
Please note “B: Menu Display and Operation”.
The term “trigger coupling” describes the way the trigger
signal is connected to the trigger unit.
AC
DC content suppressed,
DC
peak value detection inactive,
HF
high pass filter cuts off frequencies below
approx. 50kHz, trigger point symbol switched
off
LF
low pass filter cuts off frequencies above
approx. 1.5kHz,
TVL
TV signal, line pulse triggering,
trigger point symbol switched off,
TVF
TV signal, frame pulse triggering,
trigger point symbol switched off.
~
line/mains triggering,
trigger point symbol switched off.
Line/mains triggering inactivates the
TRIG. SOURCE (17)
pushbutton.
In some trigger modes such as alternate triggering, some
trigger coupling modes are automatically disabled and
cannot be selected.
(21) DEL/TR. POS
..... Control knob with several functions
and related HO LED.
The knob function depends on the actual mode setting.
Analog mode.
1. Hold off time.
The hold off time function can be activated if normal
(undelayed) time base mode is present. On condition that
the
HO
LED is not lit the hold off time is set to minimum.
The
HO
LED lights up and the hold off time increases as
