RC3000 Antenna Controller | Chapter 4 | Troubleshooting |
**NO GPS NAV**. This message means that correct data streams are being received from the GPS, but the received data indicates that the GPS has not yet formulated a navigation solution (latitude and longitude.)
Under normal conditions the GPS should generate a navigation solution within 4 minutes of powering on. If the GPS has not been powered on for several weeks or if the GPS has been moved a considerable distance from the last position that it generated a navigation solution, the time it takes to generate a solution may go beyond 4 minutes. When the GPS is powered up, it assumes it is at the same lat/lon as when it was powered down. It also has stored the ephemeris data it had at that time. While powered down the GPS’ real time clock will continue to timekeep.
The GPS will not generate a navigation solution if it cannot “see” 4 satellites. Check that the GPS unit has a clear view of the sky. If parked next to a tall building, even if the GPS has a seemingly clear view of the sky, the current GPS satellite constellation may be such that too many satellites are masked.
RF Interference. Strong interference from transmitting antennas close to the GPS receiver may also disrupt the receiver’s ability to “see” satellites. Attempt to turn off transmitting sources (satellite phones, etc.) close to the GPS antenna to see if that affects the GPS’ performance.
4.5 Fluxgate Compass
The interface between the RC3000 and the optional fluxgate compass is via a
NO COMPASS. This message indicates that the compass_present item in the System Components (3.3.1.2.1) configuration item has been set to 0 indicating that no compass is attached to the RC3000. No attempt will be made to parse compass data in this state. If a compass is truly attached, set the compass_present item to 1 or 2. Note that if the compass option was not purchased with the controller, the compass_present item will not be allowed to be set to a value other than 0.
“*****” in compass data field. The “*****” string in a position where compass data should normally appear indicates that the RC3000 cannot parse a valid heading string from the compass. Use the Fluxgate Serial Port Maintenance screen (3.3.2.7) to see if data from the compass is arriving at the RC3000.
If the heading string within the compass data shows “800.0” instead of a valid heading value (0.0 to 359.9), the compass is reporting that the magnetic field it is sensing is either too high or too low. Usually this means that another strong magnetic field is close to the compass. Try to relocate the compass away from any sources of magnetic fields (generators, air conditioners, etc.) Sometimes equipment that normally doesn’t generate a magnetic field may become magnetized by some event such as a nearby lighting strike.
COMM ERROR during compass calibration. During a compass calibration procedure, the RC3000 sends commands to the compass and checks for correct replies. The COMM ERROR message indicates that a) a response from the compass was not received correctly or b) the calibration command from the RC3000 was not received by the compass. First check communication from the compass as above. If correct data is coming from the compass, then inspect the wiring to determine if the transmit (from RC3000 to compass) line is correct.
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