Hameg HM504-2, Manual

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Subject to change without notice
16
base setting, but can be changed in the pulldown menu. The
oscilloscope automatically determines the channel switching
mode after a change of the time base setting.
“chp” (Chopped):
Indicates chopped mode, whereby the channel switching
occurs constantly between channel I and II during each
sweep. This channel switching mode occurs when any time
base setting between 500 ms/div and 500 µs/div has been
chosen.
“alt” (Alternate):
Indicates alternate channel switching. After each time base
sweep the instrument internally switches over from channel
I to channel II and vice versa. This channel switching mode
is automatically selected if any time coefficient from 200 µs/
div to 50 ns/div is active.
“add” (Addition):
The readout indicates this mode by a ”+” sign located
between both channel deflection coefficients. In addition
mode, two signals (channel I and II) are displayed as one
signal. The Y position of the signal can be influenced by both
Y-POS/CURS.I [6] and Y-POS/CURS.II [8] controls. For
correct measurements the deflection coefficients for both
channels must be equal. While the trigger mode is not
affected, the trigger point symbol is switched off.
Whether the algebraic sum (addition) or the difference
(subtraction) of both input signals is displayed, depends on
the phase relationship and the INV (invert function) setting.
XY mode:
In XY mode the deflection coefficients are displayed as
”X...” for channel I and ”Y...” for channel II, followed by
”XY” . The following READOUT information is switched off:
time deflection coefficient, trigger source, slope, coupling
and trigger point symbol.
In addition to all trigger and time base related controls, the
Y-
POS/CURS.I- knob [7] is deactivated. For X-position alteration,
the X-POS.- knob [12] can be used.
The front panel shows that the DUAL MENU push button [16]
can also be depressed together with the CH II pushbutton
[19] . Please note item [19].
[17] TRIG. SOURCE – Pushbutton.
This pushbutton is for trigger source selection and deactivated
if line (mains) triggering is selected or XY operation is chosen.
The term “trigger source” describes the source from which
the signal used for triggering originates. The measuring
amplifiers (internal triggering) or the BNC socket which
serves as an input for externally applied signals (external
triggering) can be used as a trigger source.
Single channel operation (CH I or CH II):
Briefly pressing switches the trigger source over without
displaying the Pulldown menu. During single channel operation
the internal trigger signal (originating from channel I or
channel II) or the external trigger signal can be chosen.
DUAL and Addition mode:
Briefly pressing opens the trigger source Pulldown menu
with the actual setting highlighted.
Please note “B: Menu
Display and Operation”.
The following listing shows the possible trigger sources and
how they are indicated by the READOUT. Their availability
depends on the actual channel operation mode.
„Y1“: The measurement amplifier of channel I serves as
Pulldown trigger source.
„Y2“: The measurement amplifier of channel II serves as
trigger source.
„alt“: Alternate triggering can be chosen if DUAL mode is
present. In alternate trigger mode, the switch over of the
internal trigger sources “Y1” and “Y2” is carried out
synchronously with the alternate channel switching and the
trigger point symbol is switched off.
As alternate triggering requires alternate channel operation,
alternate channel switching is set automatically. A change of
the time coefficient then has no affect regarding the channel
switching mode.
The following trigger coupling settings can not be chosen in
combination with alternate triggering:
TVL , TVF and line
(mains).
If “add” (addition) or delayed time base mode (“sea”, “del”
or “dTr”) is present, alternate triggering is not available.
Therefore alternate triggering is automatically switched off if
one of these modes has been chosen.
“ext”: External trigger mode is available in all time base and
trigger coupling modes except line/mains triggering. Then
the TRIG.EXT. BNC-socket
[30] 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.
[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
Controls and Readout
Y-POS / CURS.I
VOLTS / DIV.
CH I CH II DEL.MODE Z-ON/OFF
Y-POS / CURS.II LEVEL X-POS.
CURSOR
POS
VOLTS / DIV.
DEL.POS.
TRIG.
SOURCE
DUAL
MENU
TIME / DIV.
20V 1mV 20V 1mV 0.5s 50ns
NM
AT
X-
MAG.
PUSH
BOTH
PUSH
LONG
INV. VAR.
VAR.
ON
OFF
VAR.
TRIG. MODE
MENU
6 7 9 8 11 13 12 10
14
15 17 19 16 24 21 22 23 20
18
VAR
CUR
VAR
TR
NM
HO
VAR
x10