Rohde & Schwarz FSW13, Руководство пользователя

Страница: 398 / 1150

Common Measurement Settings
R&S
®
FSW
398 User Manual 1173.9411.02 ─ 19
RF Attenuation
Defines the attenuation applied to the RF input.
Attenuation Mode / Value ← RF Attenuation
The RF attenuation can be set automatically as a function of the selected reference
level (Auto mode). This ensures that the optimum RF attenuation is always used. It is
the default setting. By default and when
Using Electronic Attenuation (Option B25) is
not available, mechanical attenuation is applied.
In "Manual" mode, you can set the RF attenuation in 1 dB steps (down to 0 dB, also
using the rotary knob). Other entries are rounded to the next integer value. The range
is specified in the data sheet. If the defined reference level cannot be set for the
defined RF attenuation, the reference level is adjusted accordingly and the warning
"Limit reached" is displayed.
NOTICE! Risk of hardware damage due to high power levels. When decreasing the
attenuation manually, ensure that the power level does not exceed the maximum level
allowed at the RF input, as an overload may lead to hardware damage.
For details see
chapter 6.4.1.2, "RF Attenuation" , on page 394.
Remote command:
INPut:
​
ATTenuation
​
on page 846
INPut:
​
ATTenuation:
​
AUTO
​
on page 846
Using Electronic Attenuation (Option B25)
If option R&S FSW-B25 is installed, you can also activate an electronic attenuator.
In "Auto" mode, the settings are defined automatically; in "Manual" mode, you can
define the mechanical and electronic attenuation separately.
Note: Electronic attenuation is not available for stop frequencies (or center frequencies
in zero span) >13.6 GHz.
In "Auto" mode, RF attenuation is provided by the electronic attenuator as much as
possible to reduce the amount of mechanical switching required. Mechanical attenua-
tion may provide a better signal-to-noise ratio, however.
When you switch off electronic attenuation, the RF attenuation is automatically set to
the same mode (auto/manual) as the electronic attenuation was set to. Thus, the RF
attenuation may be set to automatic mode, and the full attenuation is provided by the
mechanical attenuator, if possible.
Both the electronic and the mechanical attenuation can be varied in 1 dB steps. Other
entries are rounded to the next lower integer value.
If the defined reference level cannot be set for the given attenuation, the reference
level is adjusted accordingly and the warning "Limit reached" is displayed in the status
bar.
Remote command:
INPut:
​
EATT:
​
STATe
​
on page 847
INPut:
​
EATT:
​
AUTO
​
on page 847
INPut:
​
EATT
​
on page 847
Input Settings
Some input settings affect the measured amplitude of the signal, as well.
Amplitude and Vertical Axis Configuration