18
Subject to change without notice
vernier (variable). The current setting is displayed by the
VAR-LED located above the knob. After switching the
VAR-LED (24)
on, the deflection coefficient is still
calibrated. Turning the
VOLTS/DIV. (24)
control knob
counter clockwise reduces the signal height and the
deflection coefficient becomes uncalibrated.
The readout then displays i.e.
“Y2>...”
indicating the
uncalibrated condition instead of
“Y2:...”
. Pressing and
holding the CH II 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.
The
CH II
pushbutton can also be pressed simultaneously
with the
DUAL(22)
button.
Please note item (22).
(26) TRIG. MODE
Pushbuttons and associated indicator LEDs.
Pressing the upper or lower button selects the trigger
coupling. The actual setting is indicated by
a TRIG.
MODE-LED (26)
.
Each time the lower
TRIG. MODE
pushbutton is pressed
the trigger coupling changes in the sequence:
AC
DC content suppressed,
DC
DC content effective (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, in combination with automatic
triggering AC or normal triggering DC coupled,
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
and TRIG. LED (23) are switched off.
In some trigger modes such as alternate triggering, some
trigger coupling modes are automatically disabled and
can not be selected.
(27) DEL.POS.
Rotary knob with two functions and related HO-LED.
The
DEL.POS.
knob functions as a hold off time control,
when the time base is not working in the
SEA. (SEARCH)
or in
DEL. (DELAY)
mode. The HO-LED is not lit when the
hold off time is set to minimum. The HO-LED lights up and
the hold off time increases as the knob is rotated clockwise.
A signal sounds on reaching the maximum hold off time.
Similarly in the opposite direction until minimum hold off
time is reached (HO-LED extinguishes). The hold off time
is automatically set to minimum when the time base is
changed. (For the application of hold off time setting see
the paragraph with the same heading).
The start of the trace can be set with the
DEL.POS.
control in the time base modes
SEA. (SEARCH)
or
DEL.
(DELAY)
. See SEA. / DEL. - ON / OFF (29).
STORAGE MODE ONLY
The
DEL.POS.
control and the HO-LED are disabled,
since in this mode the hold off time is set to minimum.
The hold off time last used in the analog mode is not
saved. Consequently, the hold off time is set to minimum
when it is switched back to analog mode.
The
DEL.POS.
control cannot be used for delay setting
since neither
SEA. (SEARCH)
nor
DEL. (DELAY)
time
base operation is available.
(28) TIME/DIV.
- Control knob.
The time base is set with this knob in the TIME/DIV. field,
and the setting is displayed at the top left in the readout
(e.g. ”T:10µs”). This knob acts as the time base step
switch when the VAR-LED above it is not lit. Then, the
time deflection coefficient can be set in a 1-2-5 sequence
and the time base is calibrated. Rotating anticlockwise
increases the deflection coefficient and rotating clockwise
decreases the deflection. The control acts as a vernier
(fine adjustment) when the VAR-LED is lit.
The following description refers to the function as a time
base switch.
Attention
The different deflection coefficient ranges between the
analog and digital time bases require special conside-
ration when switching between analog and digital
modes. These are described in section (7).
ANALOG MODE ONLY
Time deflection coefficients between 500ms/div. and
50ns/div. in a 1-2-5 sequence can be selected without X-
MAG. x10 magnification. Time delay between 120ms and
200ns can be selected in the
”SEA” (SEARCH)
mode.
Time deflection coefficient range in the
”DEL” (DELAY)
mode extends from 20ms/div. to 50ns/div.
STORAGE MODE ONLY
The time base can be set to deflection coefficients
between 100s/div. and 1µs/div in storage mode, if X-
MAG x10 is inactive.
(29) SEA./DEL. - ON/OFF
pushbutton
The pushbutton is operative only in analog mode.
This button is used to switch between delayed and undelayed
time base. The delayed time base operation enables a
magnified display in X-direction which is otherwise only
possible with a second time base. Pressing and holding the
button switches from normal time base mode to
SEA.
(SEARCH)
, when currently neither
”SEA” (SEARCH)
nor
”DEL” (DELAY)
operation or
”DTR”
(triggered DELAY) is
effective. Afterwards, it can be switched between
SEA.
and
DEL.
by briefly pressing the button.
These operating modes are indicated in the readout to the
right of the trigger slope indication thus:
In case of SEARCH , ”SEA” will be displayed;
In untriggered DELAY mode, ”DEL” (DEL.) and
in triggered DELAY mode, ”DTR” (DEL.TRIG.).
Controls and readout
