Tektronix DSA8300, Руководство программиста

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Commands Listed in Alphabetical Order
Examples
PHAseref:CH5:ESTAmplitude?
might return
PHAseref:CH5:ESTAmplitude 1.5
, indicating that the instrument measured
the Channel 5 phase reference clock signal amplitude as 1.5 V
p-p
PHAseref:CH<x>:ESTFrequency? (Query Only)
Queries the estimated frequency of the phase reference clock signal on the
speci
fi ed channel, as measured by the phase reference characterization process. If
this frequency is signi fi cantly different than the frequency speci fi ed in the Input
Freq fi eld, check that the phase reference clock signal frequency value you are
using is set to the correct value.
Group Phase Reference
Syntax
PHAseref:CH<x>:ESTFrequency?
Examples
PHAseref:CH5:ESTFrequency?
might return
PHAseref:CH5:ESTFrequency 12.5e9
, indicating that the instrument
measured the Channel 5 phase reference clock signal as 12.5 GHz.
PHAseref:CH<x>:ESTQuality?e (Query Only)
Queries the estimated quality of the phase reference clock signal on the speci fi ed
channel, as measured by the phase reference characterization process. The
measurement is based on the slew rate of the phase reference clock signal, where
a higher slew rate corresponds to a higher-quality reference signal. Generally, a
higher slew rate or higher reference clock frequency results in lower system jitter.
The command returns NONE (no usable clock phase reference signal detected),
LOW, MEDIUM, or HIGH.
Group Phase Reference
Syntax
PHAseref:CH<x>:ESTQuality?
Examples
PHAseref:CH7:ESTQuality?
might return
PHAseref:CH7:ESTQuality
HIGH
, indicating that the phase reference clock signal on Channel 7 is suf fi cient to
obtain the best low jitter performance
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