Rohde & Schwarz SMB100A - Chapter 3: Repair; Instrument Design and Function Description

Instrument Function
R&S
®
SMB100A
122Operating Manual 1407.0806.32 ─ 13
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 Signal Generator 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 consideration.
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)
The RF output is protected against overloading by an external signal applied to the RF
output (see "Reverse Power Protection" on page 127).
Setting the RF level
To change the RF level, press the LEVEL key and enter the desired level. Changes to
the RF level have an immediate effect (without confirmation with the Enter key) on the
output signal.
RF Level
Enters the RF level, considering the level offset (see "RF level vs. RF output level"
on page 122).
dBm, dBuV, mV and uV can be used as the level units. The 4 unit keys are labeled with
these units.
Note: The SCPI command sets the level of the "Level" display, i.e. an entered level offset
is taken into consideration in the level value.
Remote command:
[:SOURce<hw>]:POWer[:LEVel][:IMMediate][:AMPLitude] on page 341
RF Block