Table 3: Troubleshooting The Gps/Dgps Antenna Installation - NorthStar 951X Installation Manual

Troubleshooting
common GPS/DGPS
antenna installation
problems

Table 3: Troubleshooting the GPS/DGPS antenna installation

Antenna Symptom
GPS ANTENNA Poor or no GPS signal while using the
AN150 antenna.
If 5.5 VDC low or missing with load con-
nected:
If 5.5 VDC is missing with load discon-
nected:
If 5.5 VDC is present:
DGPS ANTENNA No GPS or DGPS
Poor or no GPS signal while using the
AN205-P antenna with splitter:
If 7.75 VDC is low or missing with load con-
nected:
If 7.75 VDC is low or missing with load dis-
connected:
If 7.75 VDC is present at processor UHF
connector but not at antenna:
951/952 INSTALLATION MANUAL Revision B
Whenever possible, the best and most efficient way to troubleshoot is to
use a known-good set of cables, a splitter for combo antennas (when
applicable), and working antennas as spares for swapping.
In Table 3, "Troubleshooting the GPS/DGPS antenna installation," on
page 35, the Northstar AN150 refers to the 12-dB GPS antenna; the
Northstar 8410 coupler with whip antenna refers to the beacon receiver
whip-type (E-field) antenna; and the Northstar AN205-P refers to the
combination (combo) GPS/DGPS loop antenna with splitter.
SECTION TWO - Installing the unit
Possible Solutions/Reasons
•
Turn off any onboard transmitting
devices.
• Check for 5.5 VDC at antenna with
and without antenna load connected.
•
Check for 5.5 VDC at 951/952 BNC
connector.
•
It indicates a bad connector installa-
tion, bad GPS board, or bad AN150
antenna.
•
It indicates a bad GPS board.
•
It indicates a bad AN150. Replace the
AN150.
•
Bad splitter configuration.
• Splitter cables may be reversed for
GPS and DGPS output.
•
Check installation for correct cabling.
•
Check for 7.75 VDC at antenna with
and without antenna load (cables and
c
splitter) connected. (Use "T" connec-
tors to measure VDC under load.)
•
Check for 7.75 VDC at 951/952 UHF/
DGPS connector.
• It indicates a bad connector installa-
tion, bad differential 8500-A board,
bad AN2xx. The load is too great or
the 8500-A board is defective.
•
It indicates a bad 8500-A board, or
other internal fault.
•
It indicates bad cabling, bad connec-
tors, or a bad splitter.
a
b
Page 35