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The amplitude may be changed in either of the ways detailed in General: Numeric Editing. The
amplitude can be set in terms of peak-to-peak Volts (Vpp), r.m.s. Volts (Vrms) or dBm (referenced
to the user specified load, see the section on setting the output load; the default is 50
Ω
). For Vpp
and Vrms the level can be set assuming that the output is either open-circuit or terminated; dBm is
not available if the output load is set to HiZ
.
Note that the actual generator output impedance is
always 50
Ω
; the displayed amplitude values for other load values take this into account.
The
+/–
key will allow a negative amplitude value to be entered because the units may be
selected as dBm where a negative value is meaningful. If the units are not dBm and a negative
value is entered a warning will pop up and the value will be accepted as if it had been positive.
DC Offset
Pressing the
Offset
soft-key shows the dc offset parameter in the Edit Box and the Graph Box
changes to show that offset is being edited.
The offset may be changed in either of the ways detailed in General: Numeric Editing. During a
new offset entry the +/– key can be used at any time to set a negative offset; alternate presses
toggle the sign b and – .
High Level and Low Level
The instrument allows the amplitude and offset parameters to be entered in terms of high level and
low level. Pressing either the
Ampl
or
Offset
soft-key while it is highlighted will switch the
mode from amplitude/offset to high/low level. To return to amplitude/offset mode press the
highlighted
HiLvl
or
LoLvl
soft-key.
With high/low level mode selected the Edit Box shows the parameter, the Parameters Box shows
HIL
and
LOL
in place of
AMP
and
OFS
and the Graph Box changes to show the parameter
which is being edited.
The selected parameter may be changed in either of the ways detailed in General: Numeric Editing.
During a new entry the
+/–
key can be used at any time to set the value negative; alternate
presses toggle the sign b and –.
