R&S FSMR3000, Руководство пользователя

Страница: 142 / 733

Common Measurement Settings
R&S
®
FSMR3000
142 User Manual 1179.0116.02 ─ 02
Shifting the Display (Offset) ← Reference Level
Defines an arithmetic level offset. This offset is added to the measured level. In some
result displays, the scaling of the y-axis is changed accordingly.
Define an offset if the signal is attenuated or amplified before it is fed into the
R&S
FSMR3 so the application shows correct power results. All displayed power level
results are shifted by this value.
The setting range is ±200 dB in 0.01 dB steps.
Note, however, that the internal reference level (used to adjust the hardware settings to
the expected signal) ignores any "Reference Level Offset". Thus, it is important to keep
in mind the actual power level the R&S
FSMR3 must handle. Do not rely on the dis-
played reference level (internal reference level = displayed reference level - offset).
Remote command:
DISPlay[:WINDow<n>]:TRACe<t>:Y[:SCALe]:RLEVel:OFFSet
on page 431
RF Attenuation
Defines the attenuation applied to the RF input of the R&S FSMR3.
Attenuation Mode / Value ← RF Attenuation
The RF attenuation can be set automatically as a function of the selected reference
level (Auto mode). Automatic attenuation ensures that no overload occurs at the RF
Input connector for the current reference level. It is the default setting.
In "Manual" mode, you can set the RF attenuation in 1 dB steps (down to 0 dB). 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 refer-
ence 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 can lead to hardware damage.
Remote command:
INPut<ip>:ATTenuation
on page 431
INPut<ip>:ATTenuation:AUTO
on page 432
Input Settings
Some input settings affect the measured amplitude of the signal, as well.
The parameters "Input Coupling" and "Impedance" are identical to those in the "Input"
settings.
Preamplifier ← Input Settings
If the (optional) internal preamplifier hardware is installed, a preamplifier can be activa-
ted for the RF input signal.
"Off" Deactivates the preamplifier.
"15 dB" The RF input signal is amplified by about 15 dB.
"30 dB" The RF input signal is amplified by about 30 dB.
For FSMR3050, the input signal is amplified by 30 dB if the preamplifier is activated.
Input and Frontend