Configuring the RF Signal
R&S
®
SMW200A
565User Manual 1175.6632.02 ─ 30
"Fixed"
Fixes the attenuator and amplifier paths for the current RF level and
provides signal output with constant output VSWR. The resulting level
range is indicated under "Level Range" on page 469.
This mode is coupled with ALC, and therefore only effective when
ALC is enabled.
"Manual"
Allows you to set the Attenuation.
The user-specified nominal attenuation is useful for instruments
equipped with a mechanical step attenuator.
Similar to "Fixed" mode, relays and amplifier stages keep the speci-
fied value, providing interruption-free signal output level.
Remote command:
:OUTPut<hw>:AMODe on page 886
Attenuation
Sets the nominal attenuation of the RF signal in Mode > "Manual".
Remote command:
[:SOURce<hw>]:POWer:ATTenuation on page 1191
Level Range
Shows the interruption-free range of the level that you can use in the selected mode.
Remote command:
:OUTPut<hw>:AFIXed:RANGe:LOWer? on page 887
:OUTPut<hw>:AFIXed:RANGe:UPPer? on page 887
RF OFF Mode
Determines the state of the step attenuator, when the RF signal is switched off.
The setting is not affected by an instrument preset ([PRESET] key or *RST) and the
"Save/Recall" function. It is reset only by factory preset.
"Unchanged"
Freezes the setting of the step attenuator.
Use this mode if a constant VSWR (Voltage Standing Wave Ratio) is
required.
"Full Attenuation"
Switches to the maximum attenuation.
Use this mode for applications that require a high level of noise sup-
pression.
Note: "Full Attenuation" has higher priority than the RF level modes
Mode > Fixed or Manual.
Remote command:
[:SOURce<hw>]:POWer:ATTenuation:RFOFf:MODE on page 1191
8.9.1.2 Reverse Power Protection
The R&S SMW is equipped with a reverse power protection circuit.
The reverse power protection is tripped when the power of signals reflected from the
load or external signals applied to the RF output get too high. A relay opens and inter-
Improving Level Performance
To Next Page
Loading...