R&S SMJ100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMJ100A
215 Operating Manual 1403.7458.32 ─ 14
5.5.6 RF Level
5.5.6.1 Overview of RF Level
Message "Level overrange/underrange"
If this message appears in the status line, the following parameter is in the overrange
(see data sheet):
●
the set level ("Level")
●
the displayed peak envelope power ("PEP") for Digital Modulation or Digital Stan-
dard
In this case, the signal level at the output can deviate from the set value.
The value of the RF level is displayed in the level field in the header of the instrument's
display and the easiest way to set the RF level is to set it directly in this field.
The center line ("Level") and, to the left of this, the peak envelope power ("PEP") of the
modulated RF output signal is displayed in the case of digital modulation or digital
standard.
Be aware, that there is a difference between the RF level displayed in the header and
the RF output level set in the "Level/EMF" dialog of the "RF" block.
RF level vs. RF output level
The level entered and displayed in the "Level" field takes the offset of any downstream
attenuators/amplifiers into consideration by way of calculation. This means that with a
level offset the level displayed in the header does not correspond to the level at the RF
output, but rather to the level at the output of the downstream instrument.
This allows the desired level at the output of downstream instruments to be entered.
The R&S
SMJ changes the RF output level according to the set offset.
However, the level entered and displayed in the "Level" menu of the "RF" function
block always corresponds to the RF output level. Any level offset is not taken into con-
sideration.
The level offset is entered in the "Level" menu. Here it is also possible to set the level
without taking the offset into consideration, and to make other settings, such as level
offset, attenuator mode, power-on state.
The correlation is as follows:
"Level" (in header) = "RF output level" (Level in menu) + "Level offset" (Offset in menu)
RF Signal and Analog Modulations - RF Block