Chapter 2 71
Instrument Functions: A - L
Auto Couple
Instrument Functions: A - L

2.1 Auto Couple

Coupled functions are functions that are linked/dependent on other functions. Pressing
Auto Couple displays some of the most important coupled analyzer functions.
An example of a coupled function is Res BW (resolution bandwidth). When Res BW is set to
auto, the Res BW is automatically set based on the span setting.
Coupled functions are affected depending on how they are coupled. For example, Video BW
is coupled to Res BW, so changing Res BW affects Video BW, but changing Video BW does
not affect Res BW. Changing Video BW puts it in manual (instead of auto-coupled). When
Video BW is set to Man it is unaffected by Res BW changes.
When a function is in the Man state, a #will appear next to its annotation on the display. If
one or more functions are manually set so that the amplitude or frequency measurement
becomes uncalibrated, “Meas Uncal” appears on the top right side of the graticule.

2.1.1 Auto All

Auto-couples all coupled functions. If Auto All is pressed all coupled functions are set to Auto.
Setting any auto coupled function to Man (manual), uncouples that function without
changing the coupling of other functions.
Coupled functions are functions that are linked. When Auto All is pressed, the analyzer
automatically couples all instrument settings that have auto/man choices. In most cases,
these auto settings give the most accurate measurements and optimum dynamic range.
When a function is coupled, it is in the Auto state. When it is uncoupled it is in the Man
state.
Key Path: Auto Couple
Dependencies/
Couplings: When segmented sweep is on, this key is not available (greyed out).
When Auto All is selected:
•Resolution BW couples to: Span and Span/RBW
•Video BW couples to: Res BW and VBW/RBW
•Sweep Time couples to: Res BW;Video BW;Detector;Span and Center Frequency
•CF Step couples to: Span in swept spans, to Res BW in zero span
•Attenuation couples to: Ref Level;Ext Amp Gain;Atten Step;Max Mixer Lvl;and
Int Preamp
•FFT & Sweep couples to: Res BW and Span
•PhNoise Opt (phase noise optimization) couples to: Res BW;Span and FFT &
Sweep sweep type
•Detector couples to: marker functions; Avg/VBW Type;Average On Off;Max
Hold and Min Hold
•Average Type couples to: the marker functions; Detector and Scale Type
•ADC Dither couples to: Sweep Type;Span;Res BW;ADC Ranging and FFTs/Span