R&S ZVB - Page 538

R&S
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ZVA / R&S
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ZVB / R&S
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ZVT GUI Reference
System Menu
Operating Manual 1145.1084.12 – 30 523
 The Port Power Limits limit the source power at the analyzer ports or at the output ports of
previously configured external generators. The limits are also valid for measurements with
variable source power.
 Is any Direct Generator or Receiver Access in Use? should be selected if the additional
connectors of option R&S ZVA<frequency>-B16, Direct Generator and Receiver Access, are used
and if an automatic level control (ALC) is active. With this scenario, the ALC is limited to +1 dB so
that the active port power limits cannot be exceeded by more than 1 dB.
 Meaning of Source Power Settings... defines the power reference for the true differential mode;
see Source Power in True Differential Mode.
 RF Off Behavior configures the behavior of the RF Off switches in the Channel – Power
Bandwidth Average menu and in the Source section of the Port Configuration dialog. In the factory
default configuration, only the RF source signal is turned off; the RF amplifiers are still power
supplied. In the alternative configuration, the power supply of the RF amplifiers is turned off, too.
This further reduces the broadband noise at the source port, however, the required switch-on and
settling times introduce an additional delay.
 Power Reduction at Sweep End is intended for measurements (primarily: power sweeps) on
sensitive DUTs. If enabled, at sweep end the output power of the driving port is reduced as if
the channel base power was set to its minimum possible value.
Note: The power is not reduced if there's only a single channel with a single driving port,
performing a Time or CW Mode sweep.
Use port power limits if you want to ensure that sensitive DUTs are protected from excess input
levels. Keep in mind that you have to disable the limits explicitly if you want to use the full output level
range of your analyzer again. Note that the port power limits are ignored while an ALC loop is active. A
small ALC control range will ensure low signal levels.
Remote control
SOURce<Ch>:POWer<Pt>[:LEVel][:IMMediate]LLIMit[:STATe]
SOURce<Ch>:POWer<Pt>[:LEVel][:IMMediate]LLIMit:VALue
SOURce<Ch>:POWer<Pt>[:LEVel][:IMMediate]:LLIMit:DGRaccess