10.2 Event and 1 PPS Deviation Recording
91
0.9999999 seconds). By normalizing the 16 fractional second values around 0.0000000, the range of results
from the deviation computations will be centered on zero (-0.4999999 to +0.5000000 seconds). Statistical
computations are then performed on the 16 values to determine their Mean and Sigma (Standard Deviation)
values, which are then displayed on the front panel or output via the Utility software.
10.2.5
Event Timer Input Channel Configuration
In order for the Model 1201B/C to receive an event at one of the input connectors, adjustments to both
the hardware and software configuration may be required.
The hardware configuration is described in
Section 5.2.7 and Section 5.2.6.
10.2.6
Firmware Setup
To display of Event Time Data or 1 PPS Deviation, use . See Figure 8.18 for detail on configuring the
Event/Deviation parameters from the front panel. See Section 11.2.3 for details on using the RS-232 interface.
10.2.7
Displaying Data
Event and deviation data can be accessed from either the front panel or via the clock utility software or
RS-232 commands. The following paragraphs describe the steps required to access data using the front
panel.
1. Press the TIMING key until reaching EVENT/DEVIATION menu, then press ENTER.
2. Press the UP or DOWN keys to scroll through the recorded events.
CH A EVENT
#
nn TZ
ddd:hh:mm:ss.sssssss
Where:
nn = event number (01 to 25)
ddd = day of year of the event (1 to 366)
hh = hour of the event (00 to 23)
mm = minute of the event (00 to 59)
ss.sssssss = second and fractional second of the event (e.g. 59.9999999)
TZ = time zone: either UTC or LOCAL
To scroll through any recorded events presently stored in the event-time buffer, press the UP or DOWN
key. If the event display mode is exited and then re-entered, the first event data displayed for a given channel
will correspond to the same event number as was last displayed for that channel. However, the data itself
may be changed if it has been overwritten.
10.2.8
1 PPS Deviation
If the event capture channel is configured for 1 PPS Deviation (via Event/Deviation Setup Menu), the
readout will display the deviation of the 1 PPS input signal. In this case, the readout display will have the
format:
A 1 PPS XXXXX.XX
µ
S
SIGMA: XXXXX.XX
µ
S
Where: The top number is the mean (average) value of the most recent 16 records in the event buffer, and
represents the mean deviation (in microseconds) of the measured 1 PPS input signal compared to the GNSS
Summary of Contents for 1201B
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Page 153: ...B 7 Four Fiber Optic Outputs 135 Figure B 4 Jumper Locations ...