Jackson Labs PHASE STATION 53100A, Руководство пользователя

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PhaseStation 53100A User’s Manual V1.04 25-Apr-2022 188
If not overridden by a command-line argument, the
/phaserate
value defaults to 100
samples per second. Note that some legacy Symmetricom/Microsemi 51XXA
applications may require a phase data rate of 1000 samples per second. Unlike these
test sets, any changes made to parameters such as
phaserate , tau0 , and referencefreq
will not affect either queried or streamed data from the measurement in progress. As a
result, the data rate must either be set from the command line when TSERVE is started,
or by issuing a
set phaserate command prior to the start command.
/referencefreq:<MHz>
At measurement startup time, TSERVE estimates the frequency of the signal at the 53100A’s
REFERENCE input by rounding it to the nearest 100 kHz. This provides an authoritative basis for
calculation of the applied DUT input frequency, assuming that the reference frequency is indeed
a multiple of 100 kHz. If this is not the case, you should use the
/referencefreq
option to specify
the nominal reference frequency explicitly.
For example, if a 10.5 MHz oscillator is used as a reference source, the
/referencefreq
parameter
does not need to be specified. However, if a 10.23 MHz oscillator is used as the reference, it is
necessary to specify
/referencefreq:10.23
to avoid inaccurate results.
The nominal reference frequency can be changed by remote clients with set referencefreq .
Whether it is measured or specified, the reference frequency is inherited by Telnet command
clients at connection time and used as the
referencefreq parameter during subsequent
measurements. Any changes made with set referencefreq while a measurement is in progress
will have no effect on frequency-count or streamed frequency/phase-difference readings
reported during the current measurement.
/roundfreq:<MHz>
By default, the DUT and reference input frequencies are measured at acquisition startup
time and rounded to the nearest 100 kHz. These nominal frequencies are reported by
the
show inputs command and used as the basis for phase-difference readings. If either
frequency does not accurately reflect the nominal frequency of the corresponding input
source, the discrepancy will appear as a nonzero slope in successive phase-difference
readings. If the phase slope is due to insufficient DUT frequency precision, the
/roundfreq
option can be used to force the nominal input frequency to be logged at
higher precision. Alternatively,
/inputfreq
can be used to specify the precise DUT input
frequency to be used instead of the estimated value.
For example, if a DUT with a nominal frequency of 10.23 MHz is being measured and it is
desirable to minimize the slope of the phase-difference readings , either
/inputfreq:10.23
or
/roundfreq:0.01
could be used. The show inputs command will
report an input frequency of 10.23 MHz in either case.