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GNSS Antenna and Cable Information
4.2
Verifying Antenna and Cable Operation
A two-color operate LED, located at the base of the antenna, indicates proper antenna operation.
GREEN indicates proper operation (i.e. the antenna is getting the correct voltage); ORANGE
indicates improper operation (i.e. the voltage is low).
4.2.1
Checking the Antenna Voltage
The Model 1133A pr5 Vdc to the GNSS antenna, which is carried through the antenna
cable. Nominal antenna current is 30 mA. Check the voltage at the antenna connector on the rear
panel. Without the 5-volt signal, the clock will not synchronize with the Global Positioning System
and will generate an out-of-lock alarm.
4.2.2
Power Supply Check
The Antenna Voltage test (above) actually tests the main power supply voltage of the Model 1133A.
This signal should be between 4.9 and 5.1 Vdc.
4.2.3
Checking the Antenna Resistance
Checking the internal resistance of the Arbiter GNSS antenna is not as useful as verifying the
antenna operation mentioned above. Antenna resistance measures several megohms with meter
probes at one polarity and less so if you change the meter probe polarity.
4.3
GNSS Surge Arrester
Figure 4.4 illustrates the GNSS surge arrester kit (P/N AS0094500), which is mounted in line
with the antenna cable. The surge suppressor has two female F connectors and a ground lug with
hardware for connecting to a solid ground. The case is also ground.
Figure 4.4: GNSS Surge Arrester
4.3.1
Using the Antenna Surge Arrester
Before installation, review the documentation on this device found in Appendix B. The AS0094500
surge arrester is weatherproof except for the F connectors, which may be sealed with rubber port
seals or GE Silicone II compound.