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Subject to change without notice

C o n t r o l s a n d R e a d o u t

29.1.3

50Ω / 1 MΩ Input Impedance

This function allows you to select the input impedance of chan-
nel 2. For measurement of low and high frequencies, voltages
at sources with impedances deviating from 50Ω an impedance
setting of 1 MΩ is recommended, together with the use of a
frequency compensated divider probe for minimum capacitive
load.

If the source impedance is 50Ω and the voltage to be measured
is within the voltage limits a 50Ω cable and 50Ω impedance
setting should be used.

29.2 Ground (GND) On Off

The pushbutton will alternate between switching the ampliﬁ er
input to the signal or to ground.
If the signal is disconnected respectively the ampliﬁ er input
connected to ground the readout will show a ground symbol
behind the sensitivity indication. In automatic trigger mode the
trace will be visible in a reference position which can be used as
a 0 V ground reference. The readout will show a symbol ( ) for
0 V which will be close to the vertical centre line of the graticule,
it is the zero reference for any measurements.
Referred to the trace position 0 V a DC voltage may be measured
after the input was returned to the signal.

29.3 Invert On Off

The pushbutton will alternate between not inverted and inverted.
An inverted signal will be indicated in the readout by bar above
the channel symbol. The trigger signal taken from an input will
not be affected.

29.4 Variable On Off

If activated (“On” intensiﬁ ed) the CH2 VAR pushbutton

will

be illuminated and the VOLTS/DIV VAR knob

will function as

variable which can change the sensitivity continuously between
1 mV/cm to

20 V/cm. If in uncalibrated position, the readout

will replace ”:“ by ”

“ (e.g. ”CH2

5mV“.) and this also in any

cursor measurements indicating that the sensitivity is unca-
librated.
Pressing the “Variable On Off” function key again, switches
“Variable” off and the VOLTS/DIV VAR knob

back to calibrated

1-2-5 sequence deﬂ ection coefﬁ cient function.

29.5 Probe

The menu display depends on whether the probe has dividing
ratio identiﬁ cation. The value (automatically or manually selec-
ted) will be automatically taken into account regarding the
sensitivity indicated and measurements.

29.5.1

If a HAMEG probe with automatic dividing ratio identi-

ﬁ cation is used, the menu display shows in normal intensity
“Probe” and beneath the dividing ratio (e.g. “*10”).

29.5.2

If no probe or a probe without automatic dividing ratio

identiﬁ cation is used, the menu displays “Probe” and beneath
the last manually selected dividing ratio: the INTENS knob

symbol. Pressing the allocated function key causes “Probe” to be
displayed intensiﬁ ed and the FOCUS TRACE MENU pushbutton
illuminated. The INTENS knob

then can be used for manual

selecting the dividing ratio of the applied probe. If no probe is
applied “*1” should be selected.

INPUT CH1

(BNC connector)

This is the CH1 signal input connector. In Yt mode it is a Y input,
in XY-mode it is the X signal input. The connector housing is
connected to the instrument housing and thus to safety ground.
The ring around the connector is the probe identiﬁ cation contact,
no voltage may be applied here.

INPUT CH2

(BNC connector)

This is the CH2 signal input connector. It is a Y input in Yt and XY
mode. The connector housing is connected to the instrument
housing and thus to safety ground. The ring around the connector is
the probe identiﬁ cation contact, no voltage may be applied here.

AUX pushbutton

This pushbutton belongs to AUXILIARY INPUT

(additional

input). The menu called by this pushbutton will depend upon
the actual operating mode.

VAR

x10

FOCUS
TRACE

VOLTS / DIV

VAR

VOLTS / DIV

VAR

TIME / DIV