[CA] [CA11] EV-1 Cycles 360 Degrees (Even While Docked)

[Chuck - Raymarine - Moderator]

DAL,

Q1. It's a bright, sunny day today and HDOP values have ranged from 0.7-1.3.
A1. With modern GPS receivers, cloud cover and weather have little impact upon GPS performance. The reported HDOP remains high and may indeed be associated with the reported issue. Please click here to view a FAQ addressing GPS accuracy and other factors which may affect it.

Q2. We traced the GPS Sensor lead from the cabin roof to our Raymarine E32158 AIS transceiver. All connections and contacts appear intact, and we noted no kinks in the coax cable connecting the two components. The AIS transceiver is integrated into our Raymarine nav suite via a Raymarine HS5 Network Switch.
A2. From the standpoint of how an AIS650 would be interfaced to the system of MFDs lacking a NMEA 0183 communications interface, the AIS650 is designed to be interfaced as a spur to the system's powered and properly terminated SeaTalkng / NMEA 2000 backbone, not to a HS5 RayNet Network Switch. The latter would be used to interface compatible devices having an Ethernet communications interface to the system.

Passive GPS antennas are designed to collect GPS satellite signals and pass them to a GPS receiver (ex. AIS650, AIS700, Axiom Pro MFDs, eS-Series MFDs, etc.). Accordingly, these GPS antennas must be directly connected to the device housing a GPS receiver. In contrast, a GPS sensor combines a GPS antenna and GPS receiver within a single package (ex. Raystar 150 GPS Sensor, etc.). While Raymarine's Class B AIS transceivers feature an internal GPS receiver which is designed to be interfaced to the supplied passive GPS antenna (as opposed to a GPS sensor), Raymarine's Class B AIS transceivers are not designed to transmit processed GPS data to the system via the Raymarine's Class B AIS transceivers's SeaTalkng / NMEA 2000 communications interface. Accordingly, the AIS650 in conjunction with its passive GPS antenna is not function as the GPS data source for the rest of the Raymarine system. Instead, the GPS receiver within one of the MFDs installed onboard would appear to be acting as the system's GPS data source.

As these MFDs have been installed in a location which does not afford them an unobstructed view of the skies overhead and higher than normal HDOP is being reported, it would be recommended that a Raystar 150 GPS Sensor added to the system. This GPS sensor should likewise be installed in a location affording it an unobstructed view of the skies overhead. After doing so, the Data Sources feature of the system's i70 MFID (preferred) or Data Master MFD should be used to manually select the Raystar 150 GPS Sensor as the system's Data Source for GPS data, Time & Date data, and for Datum data. Alternatively, should there be a belief that the internal GPS receiver within one or both of the system's MFDs is not performing properly, then these MFD may be sent to Raymarine’s Product Repair Center to be bench checked / serviced.