Jackson Labs PHASE STATION 53100A, User Manual

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PhaseStation 53100A User’s Manual V1.04 25-Apr-2022 189
Note that the accuracy of the absolute frequency readings obtained with the
/format:F
switch depends only on the reference source, regardless of the nominal input frequency
reported by
show inputs . Consequently, it is unaffected by the
/inputfreq
or
/roundfreq
options. As a result, the /inputfreq and /roundfreq options are not required in most
TSERVE measurements. However, note that if the nominal reference frequency is not a
multiple of 100 kHz, it is necessary
to use
/referencefreq
to avoid inaccurate results
regardless of the selected output format. There is no corresponding way to increase the
reference frequency’s rounding precision; the nominal reference frequency must be
specified explicitly with
/referencefreq
if 100-kHz precision is insufficient.
/ sep:<character>
/ timestamp:<s, MJD, UNIX>
These related options cause TSERVE to add a timestamp to each phase-difference or
frequency reading that is written to a shared file or streamed to network clients.
By default, no timestamps are emitted. When
/timestamp:MJD
is specified, the
Modified Julian Date (MJD) associated with each phase-difference or frequency value
will be written as the first numeric field on each line, followed by a space character
(ASCII 32), then the measurement value itself. MJD timestamps are generated with six
digits of decimal precision, resulting in roughly 10 unique MJD values per second.
You can also use
/timestamp:s
to emit a simple numeric timestamp at one-microsecond
precision. These timestamps begin at 0.000000 for the first reading acquired. Finally,
/timestamp:UNIX
can be used to request numeric timestamps at one-millisecond
precision relative to the standard Unix epoch (January 1
st
, 1970 at 00:00:00 UTC.)
In all cases, the difference between successive timestamps will be equal to the
reciprocal of the
/phaserate
parameter, whose default is 100 readings per second,
scaled further by any specified
/phasedec
ratio beyond its default value of 2:1. Refer to
the description of the
/phaserate
parameter for more information.