30
Subject to change without notice
First Time Operation
1.1.2 Y AMP
1.1.3 TRIGGER AMP
1.1.4 X MAG POS
1.1.5 CT X POS
1.1.6 STORE AMP
Each item may be called only on condition that no signal is
applied at the BNC sockets. Further information can be found
under “Adjustments”.
1.2 MANUAL ADJUSTMENT
contains menu items which are available only for HAMEG
authorized workshops.
2. SETUP & INFO
contains the submenus:
2.1 MISCELLANEOUS
Active functions are marked by “x”. “Set” changes
from active to inactive and vice versa.
2.1.1 CONTROL BEEP.
In OFF condition the acoustic signals actuated by the
control limits areswitched off.
2.1.2 ERROR BEEP.
Acoustic signals indicating faulty operation are suppressed
in OFF condition.
2.1.3 QUICK START.
In condition ON neither the HAMEG logo nor the check
and initialisation are displayed by the readout. Then the
instrument is quickly ready for operation.
2.2 FACTORY
contains menu items which are available only for HAMEG
authorized workshops.
2.3 INFO.
Displays information regarding the instrument’s hardware
and software.
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 afterwards the device under test.
The oscilloscope is switched on by depressing the red
POWER
pushbutton. After a few seconds the
HAMEG
logo and the
instrument software release is displayed on the screen, if this
function is active. As long as the
HAMEG
logo is visible different
internal checks are made. Thereafter the instrument will revert
to its last used operating mode.
If after that no trace is visible, the
AUTOSET
pushbutton should
be pressed briefly. This selects the Yt mode and medium trace
and readout intensity (
please note
”AUTOSET”
). Adjust Y POS.I
and X POS.
.
.
.
. controls to center the baseline. Set
INT./FOC
..... for
suitable brightness
brightness
brightness
brightness
brightness (intensity) and for optimum sharpness
sharpness
sharpness
sharpness
sharpness
(focus) of the trace. The oscilloscope is now ready for use.
If the
AUTOSET
function was not used and only a spot appears
(CAUTION! CRT phosphor can be damaged), reduce 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 centred trace may not align exactly with the
horizontal center line of the graticule. A few degrees of misalignment
can be corrected. Please note “Controls and Readout” section “D:
Controls and readout item (3) TRACE ROT.”.
Probe compensation and use
To display an undistorted waveform on an oscilloscope, the probe
must be matched to the individual input impedance of the Y
amplifier.
For this purpose a square wave signal with a very fast rise time
and minimum overshoot should be used, as the sinusoidal
contents cover a wide frequency range.
The built in calibration generator provides a square wave signal
with selectable frequencies and a very fast risetime (<4ns)
from the output socket below the CRT screen.
As the squarewave signals are used for probe compensation
adjustments, neither the frequency accuracy nor the pulse duty
factor are of importance and therefore not specified. The output
provides 0.2Vpp ±1% (tr <4ns) for 10:1 probes. When the Y
deflection coefficient is set to 5mV/div, the calibration voltage
corresponds to a vertical display of 4 divisions (10:1 probe).
The output socket has an internal diameter of 4.9mm to
accommodate the internationally accepted shielding tube
diameter of modern probes and F series slimline probes. Only
this type of construction ensures the extremely short ground
connections which are essential for an undistorted waveform
reproduction of non sinusoidal high frequency signals.
Adjustment at 1kHz
The C-trimmer adjustment (low frequency) compensates the
capacitive loading on the oscilloscope input. By this adjustment,
the capacitive division assumes the same ratio as the ohmic
voltage divider to ensure the same division ratio for high and low
frequencies, as for DC. (For 1:1 probes or switchable probes set
to 1:1, this adjustment is neither required nor possible). A baseline
parallel to the horizontal graticule lines is essential for accurate
probe adjustments. (See also ”Trace rotation TR”).
