Jackson Labs PHASE STATION 53100A, Руководство пользователя

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PhaseStation 53100A User’s Manual V1.04 25-Apr-2022 203
In the example above, the DUT signal was generated by a DDS synthesizer tuned to a
nominal frequency of 10.123456 MHz. This value will be reported by the
show inputs
query as 10.1 MHz unless
/inputfreq
,
/roundfreq
, or set inputfreq has been used to
establish a more precise nominal DUT input frequency. The readings from show
fcounter are more accurate as well as more precise than show inputs , displaying
consistent error that reveals the synthesizer’s limited tuning precision. Multiplying 10.1
MHz by one of the reported frequency difference readings near 2.322…E-3 and adding
the result back to 10.1 MHz yields a similarly-precise absolute frequency count.
- show inputs
Returns amplitude readings and rounded or specified frequency readings for the signals
at the 53100A’s REFERENCE and DUT input ports, as shown in Figure 83 above.
Unlike the TSC 51XXA implementation of this command, both the ‘Current’ and ‘Last
Collection’ values reflect the state of the measurement in progress. If no measurement
is running at the time
show inputs is issued, the message
No measurement in progress
will be returned.
- show inputfreq
Returns the nominal DUT input frequency used for phase-difference calculations and the
show inputs
command. See the description of the
/inputfreq
command-line parameter
for more information.
- show ipn
Returns a chart showing integrated phase noise in units of radians over various portions
of the Fourier spectrum, with and without the influence of coherent spurs.
Each row in the chart reports the jitter at limits of integration between the given offset
shown at left and the maximum offset supported by the PhaseStation hardware,
normally 1 MHz. Lower integration limits from 0.01 Hz to 10000 Hz are supported. In
the example shown above (Figure 84), the measurement has been running long enough
to provide data at a minimum lower integration limit of 0.1 Hz.
Figure 84