Keysight Technologies N5171B EXG, Руководство пользователя

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Keysight EXG and MXG X-Series Signal Generators User’s Guide 105
Optimize Performance
Using Unleveled Operating Modes
The FIXED, RMS, and MANUAL references use a DAC to apply the reference voltage and do not
require the IQ signal to be present.
Power Search Settings
For the power search routine to execute, the instrument must be in the following conditions:
— The I/Q modulation enabled On.
— The RF output enabled On.
— The Automatic Leveling Circuitry deactivated (Off).
— The RF Blanking set to On.
This function prevents power spikes during the power search (refer to “Using the RF Blanking
Marker Function” on page 214 .)
— When using summing for the internal Arb and the external I/Q, all four power reference modes
are available (e.g. Fixed, RMS, Manual, and Modulated).
— When using the external IQ inputs, use the MANUAL reference mode, and make sure the
external I/Q signal is present when executing a power search. If the external I/Q signal is not
present, the power search will fail.
Example: Automatic Power Search
1. Preset the signal generator.
2. Set the desired frequency.
3. Set the desired amplitude.
4. Turn the RF output on.
5. Deactivate the signal generator’s automatic :
Press
AMPTD > ALC Off On to highlight Off
Deactivating the signal generator’s automatic leveling control is a significant instrument
change that automatically initiates a power search.
The MXG/EXG reference voltage is designed to operate between 0.1 Vrms
to 1 Vrms nominally, but it can overrange to 1.414 Vrms. (The RMS can
overrange to 1.414, if the constant values are loaded manually and all “1”s
are entered for the I and Q values.) See also “Saving a Waveform’s Settings
& Parameters” on page 197 .
The minimum reference level that results in a successful power search is
dependent on RF Frequency, RF Amplitude, and Temperature. An
MXG/EXG power search using a reference level of 0.1 Vrms for 0 dBm at 1
GHz may fail.