76 Chapter2
Instrument Functions: A - L
Auto Couple
Instrument Functions: A - L
Remote Command:
[:SENSe]:SWEep:FFT:SPAN:RATio <integer>
[:SENSe]:SWEep:FFT:SPAN:RATio?
Example: SWE:FFT:SPAN:RAT 20
2.1.3 PhNoise Opt
Selects the LO (local oscillator) phase noise behavior for various operating conditions. The
selected value is displayed below the £(f) indicator on the left side of the screen. It is
preceded by #if PhNoise Opt Auto has been selected.
Key Path: Auto Couple
State Saved: Saved in instrument state
Factory Preset: Auto
Remote Command:
[:SENSe]:FREQuency:SYNThesis 1|2|3
1, selects optimization of phase noise for frequencies offset <50 kHz from the carrier.
2, selects optimization of phase noise for frequencies offset >50 kHz from the carrier.
3, selects optimization of LO for fast tuning
[:SENSe]:FREQuency:SYNThesis?
[:SENSe]:FREQuency:SYNThesis:AUTO OFF|ON|0|1
[:SENSe]:FREQuency:SYNThesis:AUTO?
Example: FREQ:SYNT:AUTO OFF
FREQ:SYNT 3, selects optimization for fast tuning
2.1.3.1 Auto
Selects the LO phase noise behavior to optimize speed or dynamic range for various
instrument operating conditions.
For PSA: the Auto rules choose Fast Tuning whenever the span ≥10.5 MHz or the Res BW
>200 kHz. Otherwise, for spans >141.4 kHz, and for Res BWs >9.1 kHz, the Auto rules
choose Optimize £(f) for f >50 kHz. All remaining cases choose Optimize £(f) for f <50 kHz.
Key Path: Auto Couple,PhNoise Opt
Remote Command:
See“PhNoiseOpt”onpage 76.
Example: FREQ:SYNT:AUTO ON