Instruction manual

27
Subject to change without notice
1.2 SETUP
This menu allows changes to the default settings
regarding the instrument behavior during operation.
The SETUP menu contains the submenus
”MISCELLANEOUS” and ”FACTORY”.
1.2.1 MISCELLANEOUS contains:
1.2.1.1 CONTROL BEEP ON/OFF.
In OFF condition the acoustic signals actuated by
the control limits are switched off.
Note:
The default setting is ON. If different conditions
are required the setting must be performed
each time after switching the oscilloscope on.
1.2.1.2 ERROR BEEP ON/OFF.
Acoustic signals indicating faulty control operation
are suppressed in OFF condition.
Note:
The default is ON. If different conditions are
required the setting must be performed each
time after switching the oscilloscope on.
1.2.1.3 QUICK START ON/OFF.
In condition ON the B&K logo and the menus
will not be displayed after switching the instrument
on. Then the instrument is quickly ready for
operation. To change from QUICK START OFF to
ON, press and hold the AUTOSET pushbutton when
switching the instrument on until the menus become
visible and change the setting from ON to OFF.
1.2.1.4 TRIG.-SYMBOL ON/OFF.
In most of the Yt (time base) modes the readout
displays a trigger point symbol which will not be
displayed in condition OFF.
1.2.1.5 DC REFERENCE ON/OFF.
If ON is selected and Yt (time base) mode is present,
the readout displays a ground symbol (
⊥⊥
⊥⊥
⊥). This symbol
eases the evaluation and determination of DC
contents by indicating the 0 Volt reference position.
1.2.1.6 EXTENDED CURSOR ON/OFF.
If ON is selected and Yt (time base) storage mode
is present, additional cursor measurement functions
are available. For further information please note item
ON/OFF – CHI/II – 1/
∆∆
∆∆
∆ t (41) in section “Controls
and Readout”.
1.2.2 FACTORY
Attention!
The submenues are available only for B&K
authorized workshops, due to very expensive
required in connection with oscilloscope adjustment.
1.3
First Time Operation
The following text assumes that the “SAFETY” section of
this manual has been read carefully and understood.
Each time before the instrument is put into operation check
that the oscilloscope is connected to protective earth. For
that reason the power cable must be connected to the
oscilloscope and the power outlet. Then the test lead(s) must
be connected to the oscilloscope input(s). Check that the
device under test is switched off and connect the test lead(s)
to the test point(s). Then switch on the instrument and after-
wards the device under test.
The oscilloscope is switched on by depressing the red
POWER pushbutton. After a few seconds the B&K logo
and the instrument software release is displayed on the
screen. As long as the B&K logo is visible different internal
checks are made. Thereafter the instrument will revert to its
last used operating mode.
If after approx. 20 seconds no trace is visible, the AUTO SET
pushbutton should be pressed briefly. This selects the Yt mode
and medium trace and readout intensity (please note “AUTO
SET”). Adjust Y-POS.I and X-POS. controls to center the
baseline. Adjust INTENS. (intensity) and FOCUS controls for
medium brightness and optimum sharpness (input(s) groun-
ded) of the trace. The oscilloscope is now ready for use.
If the AUTO SET function was not used and only a spot
appears (CAUTION! CRT phosphor can be damaged), redu-
ce the intensity immediately and check that the XY mode is
not selected (XY not displayed in the readout).
To obtain the maximum life from the cathode-ray tube, the
minimum intensity setting necessary for the measurement
in hand and the ambient light conditions should be used.
Particular care is required when a single spot is displayed, as
a very high intensity setting may cause damage to the
fluorescent screen of the CRT. Switching the oscilloscope
off and on at short intervals stresses the cathode of the CRT
and should therefore be avoided.
The instrument is so designed that even incorrect operation
will not cause serious damage.
Trace Rotation TR
In spite of Mumetal-shielding of the CRT, effects of the earth‘s
magnetic field on the horizontal trace position cannot be
completely avoided. This is dependent upon the orientation
of the oscilloscope on the place of work. A centered trace
may not align exactly with the horizontal center line of the
graticule. A few degrees of misalignment can be corrected
by a potentiometer accessible through an opening on the
front panel marked TR.
Probe compensation and use
To display an undistorted waveform on an oscilloscope, the
probe must be matched to the individual input impedance of
the vertical amplifier.
For this purpose a square wave signal with a very fast rise
time and minimum overshoot should be used, as the sinusoi-
dal contents cover a wide frequency range.
The built-in calibration generator provides a square wave signal
with a very fast rise time (<4ns), and switch-selectable
frequencies of approx. 1kHz and 1MHz from the output socket
below the CRT screen.
As the square wave signals are used for probe compensation
adjustments, neither the frequency accuracy nor the pulse
duty factor are of importance and therefore not specified.
First Time Operation