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12.17 Synchronization
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12.17
Synchronization
The standard 1133A includes an twelve-channel global positioning system (GNSS) receiver, which
provides accurate time to a fraction of a microsecond anywhere in the world. Optionally, choose
an IRIG-B decoder to synchronize the 1133A. By comparing an internal 10 MHz oscillator to the
1-PPS (pulse-per-second) output of the GNSS receiver, the 1133A maintains its frequency to within
a few parts in 10
10
. For IRIG-B synchronization (Option 07), timing signals are as accurate as the
IRIG-B clock source.
12.17.1
GNSS Information
Tracking
GPS-L1 (1575.42 MHz)
−
12 Channel, tracks up to 12
satellites depending on conditions, antenna location and
receiver model
Acquisition
2 minutes, typical
Accuracy
UTC
−
USNO
±
1
µ
s
Out-of-Lock
Via system interface and status display; optional, via
contact closure
Indication
Satellite Tracking, view from front panel, STATUS key
12.17.2
GNSS Antenna & Cable Characteristics
Power
+5 Volts DC, 30 mA nominal., supplied through antenna
cable from 1133A
Frequency
1575.42 MHz
Gain
35 dB (nominal)
VSWR
2:1
Mounting
3/4-inch NPT pipe thread (1”
−
14 marine type) mount
Dimensions
77.5 mm diameter x 66.20 mm height (3.05” x 2.61”)
Weight
170 grams (6.0 oz.)
Connections
Type-F
Cable
Type RG-6, 15 m (50 ft) included; longer cables option-
ally available
12.17.3
Synchronization Output - IRIG-B
The 1133A includes one IRIG-B output for use with synchronizing external equipment.
Type
One; two-pole; IRIG-B000 or IRIG-B003 per C37.118
(unmodulated or DC level-shift), 200 mA peak; pluggable
5-mm terminal strip with mating connector