Hameg HM504-2, Руководство пользователя

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Subject to change without notice
20
[31] MAIN MENU – READOUT – Pushbutton with double
function.
MAIN MENU
Briefly pressing calls the MAIN MENU. It contains the
submenus ADJUSTMENT and SETUP & INFO partly con-
taining further submenus. A menu description can be found
under „E: MAIN MENU“.
Although self explanatory, a description of the menu selection
and other operating functions can be found in this part of the
manual under „B: Menu Display and Operation“.
READOUT
Pressing and holding the pushbutton switches the readout
on or off. With the readout switched off, the INTENS/FOCUS
function can consequently not be set to RO.
It may be required to switch off the readout if interference is
visible on the signal(s). Such interference may also originate
from the chopper generator if the instrument is operated in
chopped DUAL mode.
All intensity and focus (INT./FOC.) settings are stored after
the instrument is switched off and present when switching
the instrument on again; however the READOUT will always
be switched on.
[32] MEASURE SET – Pushbutton with double function.
a) MEASURE:
Briefly pressing calls the “AUTO MEASURE” menu, if CUR-
SOR lines are not activated. Otherwise the “CURSOR
MEASURE” menu is displayed. Pressing and holding the
SELECT - ON/OFF-pushbutton
[34] activates or deactivates
the CURSOR lines.
Applicability of measuring functions
Where a measuring function is not supported in conjunction
with an operating mode, instead of a measuring value the
READOUT indicates “n/a” (not applicable). For example the
READOUT displays “
∆
t: n/a” if
∆
t measurement is selected
in combination with XY mode.
Uncalibrated Settings / Overflow Indication
If the deflection coefficient is uncalibrated the READOUT
indicates e.g. “Y1>2V= or >500 µs. Such conditions are
indicated by a “>” or “<” sign automatically put in front of the
displayed measuring value.
Measurement range overflow (exceeding) is indicated in
front of the measuring value by the “>” sign.
Non executability of measurements
A question mark (?) is displayed if the measuring unit can‘t
find a useful value (e.g. frequency measurement without a
signal).
b) AUTO MEASURE
The measurement results of the various menu items explained
under 32.x are related to the signal used for triggering.
For voltage measurement, AC or DC trigger coupling is
required. DC voltage measurement assumes DC input
coupling.
In the case of high frequency signals, the different frequency
responses of the trigger amplifier and Y amplifier cause a
reduction of the measurement accuracy.
If relatively low frequency signals (<20 Hz) are present, the
measurement value continuously changes, following the
waveform. The pulse duty factor of such signals also affects
the measurement result as well as the trigger slope setting.
Frequency and Period measurement assume that the trigger
condition is met (TR LED lit) and normal triggering active for
signals >20 Hz. Very low frequency signals require a
measuring time of several seconds.
To avoid measuring errors the complete signal must be
displayed within the vertical graticule limits; i.e. without
overranging.
DC shows the DC Mean Value (please note “Mean Value
Display”)
Frequency for frequency measurement. Depending on the
trigger point setting, complex signals cause different results.
Period measures the period length. Depending on the trigger
point setting, complex signals cause different results.
Peak + determines the positive peak value of an AC voltage.
The DC content is considered if DC input coupling is present.
Peak – determines the negative peak value of an AC voltage.
The DC content is considered if DC input coupling is present.
Peak Peak measures the difference voltage (AC) between
the positive and the negative peak values.
Trigger Level displays the trigger comparator reference
voltage which must be exceed for triggering.
Off automatic measurement switched off.
c) CURSOR MEASURE:
Briefly pressing the MEASURE SET pushbutton on condition
CURSOR ON
[34] calls this menu. The measurement results
of the different menu items then are related to the CURSOR
settings referring to the signal.
The Y-POS/CURS.I- [6] and Y-POS/CURS.II-knobs [8] enable
CURSOR line setting if the CURSOR POS LED is lit. Then
each CURSOR line is marked by a symbol (“I“, “II”) indicating
the relationship between each Y POS/CURS. knob and CUR-
SOR line. In cases where more than two CURSOR lines or
additionally “+” symbols are displayed, the SELECT
[34]
function switches over the assignment. If both CURSOR
lines or “+” symbols have the same marking, both can be
shifted simultaneously (Tracking function).
∆∆∆∆∆
t (display “
∆
t: measured value“)
Enables time measurement by aid of two vertical CURSOR
lines in Yt mode (not in XY mode). Briefly pressing the UNIT
(35) pushbutton directly switches over from
∆∆∆∆∆
t to 1/
∆∆∆∆∆
t
(frequency) measurement and vice versa.
Controls and Readout
INPUT CHI (X)
AC/DC/GND
max.
400Vp
1M
Ω
II
18pF
INPUT CHI (X)
max.
400Vp
1M
Ω
II
18pF
TRIG. EXT.
max.
100Vp
INP.
(Z)
x1 / x10
AC/DC/GND
x1 / x10
CAT
I
! ! !
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