337
Channel Power Measurement
Meas Setup
PhNoise Opt
Selects the LO (local oscillator) phase noise behaviour for various operating conditions.
PhNoise Opt Auto
Selects the LO (local oscillator) phase noise behavior to optimize dynamic range and speed for various
instrument operating conditions.
The X-Series has two grades of LO; a high performance LO that gives the best phase noise performance;
and a medium-performance LO that gives excellent performance.
In models with the high performance LO, Auto will choose:
Fast Tuning whenever Span > 44.44 MHz or RBW > 1.9 MHz
otherwise, if center frequency is < 195 kHz OR ALL of the following are true:
CF 1 MHz AND Span 1.3 MHz AND RBW 75 kHz
then Best Close in Phase Noise;
otherwise, Best Wide-offset Phase Noise
In models with the medium-performance LO, Auto will choose:
Fast Tuning whenever Span > 12.34 MHz or RBW > 250 kHz
otherwise, if center frequency is < 25 kHz OR ALL of the following are true:
CF >= 1 MHz AND Span <= 141.4 kHz AND RBW <= 5 kHz
then Best Close in Phase Noise;
otherwise, Best Wide-offset Phase Noise
In units whose hardware does not provide for an extra-fast tuning option, the settings for Fast Tuning are
the same as Best Close-in, so in those models you will see no difference between these settings.
These rules apply whether in swept spans, zero span, or FFT spans.
Modified at S/W Revision: A.02.00, A.03.00
Key Path: Meas Setup
Initial S/W Revision: A.04.20
Key Path: Meas Setup
Remote Command: [:SENSe]:CHPower:FREQuency:SYNThesis:AUTO[:STATe]
OFF|ON|0|1
[:SENSe]:CHPower:FREQuency:SYNThesis:AUTO[:STATe]?
Example: CHP:FREQ:SYNT:AUTO 1
CHP:FREQ:SYNT:AUTO?