Rohde & Schwarz ESW Series, User Manual

Page: 162 / 759

Common Measurement Settings
R&S
®
ESW
162 User Manual 1177.6298.02 ─ 08
Source Offset
Constant level offset for the external generator. Values from -200 dB to +200 dB in 1
dB steps are allowed. The default setting is 0
dB. Offsets are indicated by the "LVL"
label in the channel bar (see also "Displayed Information and Errors" on page 158).
Using this offset, attenuators or amplifiers at the output connector of the external gen-
erator can be taken into account. This is useful, for example, for the displayed output
power values on screen or during data entry. Positive offsets apply to an amplifier,
while negative offsets apply to an attenuator after the external generator.
Remote command:
SOURce<si>:POWer[:LEVel][:IMMediate]:OFFSet
on page 491
Source Frequency Coupling
Defines the frequency coupling mode between the R&S ESW and the generator.
For more information on coupling frequencies, see "Coupling the Frequencies"
on page 156.
"Auto" Default setting: a series of frequencies is defined (one for each
sweep point), based on the current frequency at the RF input of the
R&S
ESW (see "(Automatic) Source Frequency (Numerator/Denomi-
nator/Offset)" on page 162). The RF frequency range covers the cur-
rently defined span of the R&S ESW (unless limited by the range of
the signal generator).
"Manual" The generator uses a single fixed frequency, defined by (Manual)
Source Frequency which is displayed when you select "Manual" cou-
pling.
Remote command:
SOURce<si>:EXTernal<gen>:FREQuency:COUPling[:STATe]
on page 488
(Manual) Source Frequency
Defines the fixed frequency to be used by the generator.
Remote command:
SOURce<si>:EXTernal<gen>:FREQuency
on page 488
(Automatic) Source Frequency (Numerator/Denominator/Offset)
With automatic frequency coupling, a series of frequencies is defined (one for each
sweep point), based on the current frequency at the RF input of the R&S
ESW.
However, the frequency used by the generator may differ from the input from the
R&S
ESW. The RF frequency can be multiplied by a specified factor, or a frequency
offset can be added, or both.
Note: The input for the generator frequency is not validated, i.e. you can enter any val-
ues. However, if the allowed frequency ranges of the generator are exceeded, an error
message is displayed on the R&S
ESW. The values for Result Frequency Start and
Result Frequency Stop are corrected to comply with the range limits.
The value range for the offset depends on the selected generator. The default setting is
0
Hz. Offsets <> 0 Hz are indicated by the "FRQ" label in the channel bar. Negative
offsets can be used to define reverse sweeps.
Data Input and Output