[CA] [CA11] C80 Classic and "No Heading"

[Wings]

C80, GPS 125, SPX30, ST8002+ Autopilot head, SeaTalk 1 The autopilot is disconnected from the ST system and operates independently: the C80 shows an "X" through the "Pilot" icon. On recommendation from Derek, a Raymarine Forum moderator and very knowledgeable guy, I disconnected the ST wires (all three) that connected the SPX30 to the ST buss bars. Of course, on the 8002 display, there is only one ST connector back to the SPX30, so with the SPX30 ST connection severed, the two systems are independent.

We are having trouble with the heading information on our C80. Our C80 displays position information as well as COG and SOG information, but often lacks heading information. Today, it's behaving normally, but often, the "No Heading" system alarm sounds every 10-12 seconds, often continuing for hours. Imagine the frustration!

This is the information that we were given by Derek-the-moderator on the Raymarine Forum: "Note that Heading is derived from the SPX30 compass, whereas COG is output from the GPS sensor, the two are not related." Is the mentioned "SPX30 compass" the fluxgate compass? It's the only compass that I know in the Raymarine system. Since the Autopilot system is completely disconnected from the ST system, and therefore the C80, how is the C80 to receive any heading information?

What if a system doesn't have an autopilot? How does the system acquire heading? Surely it's from the GPS. Since, in our system, the Autopilot and the C80 aren't connected via ST, then regardless of how the SPX30 is acquiring the heading data, I don't understand how it can be transmitted to the C80. Except when it's not, the C80 displays heading information with the SPX30 disconnected.

Another interesting point is this. At this moment, the Autopilot is on and steering perfectly: it's still an independent system. We are running on a magnetic heading, so the fluxgate must be functioning, and we've never encountered problems with steering by magnetic heading. The C80 is operating perfectly and seems to have heading information: We are not receiving the "No Heading" system alarm. On the other hand, we cannot use the display choice of, "Heading Up", but only "Course Up", and "North Up". Should this mean that the C80 doesn't have heading information?

There is certainly a ghost in the system but I'm not sure what it is. The system alarm is the problem, of course, since it's persistent and overrides C80 function until the "Acknowledge" button is pressed.

1. Should we send in the C80 for repair? What would be the failure to mention?
2. Should we purchase a new GPS mushroom? Is that the failure point? Can it be repaired? The unit sometimes requires 4-5 minutes for a fix, even when we're in the same location that we de-powered the ST bus that powers the GPS.

Please note that we are manual readers and we read in the C80 manual on page 4-1, "To access full functionality your chart plotter system requires position and heading data from your boat's Global Positioning System." Later, on page 4-3, the manual states, "Note: If neither heading nor COG data is available, the vessel is shown as a solid circle.

We leave French Polynesia in a week and need to have some help in determining what, if any, of our electronics we should take home for repair. Of the Raymarine instruments that we've sent for repair neither has been repaired since they can never reproduce the problem. This has occurred with our non-functioning DSM and our wind transducer. It's not an inexpensive process.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Wings,

Q1. What if a system doesn't have an autopilot? How does the system acquire heading? Surely it's from the GPS.
A1. Negative. The Raystar 125 GPS Sensor is not capable of supplying heading data to the system. This GPS would only be capable of supplying the system with position, COG, SOG, date/time, and other data associated with the GPS position FIX. Please note that when properly interfaced to a SPX-30 autopilot course computer, the MFD would have been interfaced to SPX-30 autopilot course computer not only by SeaTalk, but also the NMEA 0183 output port of the SPX-30 would have been interfaced to the MFDs NMEA 0183 input port to supply the MFD with 10Hz stabilized heading data in support of the MFD's heading dependent features (radar overlay, MARPA, etc.). Please note that the MFD's NMEA 0183 output port should not additionally be interfaced to the autopilot's NMEA 0183 input port if both the SPX-30 and MFD are interfaced via SeaTalk or a data loop will be created. Should the MFD have been interfaced to the SPX-30 via SeaTalk communication alone, then the MFD would have only received 1Hz heading data updates from the autopilot system.

Q2. Since, in our system, the Autopilot and the C80 aren't connected via ST, then regardless of how the SPX30 is acquiring the heading data, I don't understand how it can be transmitted to the C80. Except when it's not, the C80 displays heading information with the SPX30 disconnected.
A2. See the response to Q1. One may easily verify whether this is so by temporarily configuring the MFD's NMEA Port Setting to NAVTEX 9600 (severs possible 4800 BAUD communications with the MFD), switching the entire system OFF, and then switching it ON again. Should the MFD then report a value within its Heading data item (vs. ---), then another source of heading data has been interfaced to the system which you have not yet identified.

Q3. Another interesting point is this. At this moment, the Autopilot is on and steering perfectly: it's still an independent system. We are running on a magnetic heading, so the fluxgate must be functioning, and we've never encountered problems with steering by magnetic heading. The C80 is operating perfectly and seems to have heading information: We are not receiving the "No Heading" system alarm. On the other hand, we cannot use the display choice of, "Heading Up", but only "Course Up", and "North Up". Should this mean that the C80 doesn't have heading information?
A3. Chart orientation changes may be blocked if the Chart application's Chart Sync feature has been configured ON. It is correspondingly recommended that you ensure that this configuration setting has been switched OFF

Q4. There is certainly a ghost in the system but I'm not sure what it is. The system alarm is the problem, of course, since it's persistent and overrides C80 function until the "Acknowledge" button is pressed.
A4. The persistence of heading is either due to the having additionally interfaced the SPX-30 to the MFD via NMEA 0183 communications or as has been previously specified, another source of heading is present within the system. The persistence of heading data would in no way be attributable to a problem with the MFD's circuitry.


Q5. Should we send in the C80 for repair? What would be the failure to mention?
A5. Negative. See the response Q4. Please additionally note that Raymarine's Product Repair Centers can no longer service C-Series Classic MFDs. That said and as indicated within the response to Q4, the persistence of heading data would in no way be attributable to a problem with the MFD's circuitry.

Q6. Should we purchase a new GPS mushroom? Is that the failure point? Can it be repaired? The unit sometimes requires 4-5 minutes for a fix, even when we're in the same location that we de-powered the ST bus that powers the GPS.
A6. As indicated, the GPS sensor would have not bearing upon the population of the Heading data item within your system. However, the slow GPS FIX acquisition may be indicative of a depleted CR2032 memory battery which may be fairly easily replaced. This memory battery is responsible for retaining almanac and last position data when the system is shut down, permitting quicker GPS FIX acquisition upon startup. Should you opt to replace the GPS sensor, then please click here to view a FAQ addressing this subject.

[Wings]

Thank you, Chuck, for the wonderful help.

To clarify, the 10Hz heading data enters the MFD via NMEA183, and only 1Hz data via the ST connection between the two. Isn't 1Hz enough for most purposes?

I assume that the chart application functionality is accessible via the MFD's menu on charting. I'll check that.

The check for other heading data source to the MFD is simple and I'll check immediately.

I did find info online on how to change the Raystar 125 battery. I'll try that, I think.

As an ancillary question is this. We're cruisers. The South Pacific, while beautiful and such, is a very harsh environment. Reasonably, what is the life expectancy for the Raymarine equipment that I have installed? I installed most in 2005 or so.

A second thought, related to the first, is that since it's all that old, I should buy a completely new suite of equipment and use new networking. I'm sure that it's more stable and much more robust that ST1.

Thoughts?

William

[Chuck - Raymarine - Moderator]

Q1. The 10Hz heading data enters the MFD via NMEA183, and only 1Hz data via the ST connection between the two. Isn't 1Hz enough for most purposes?
A1. MARPA requires 10Hz heading data. For other features requiring heading data (excluding the autopilot), 1Hz data will suffice for your system.

Q2. As an ancillary question is this. We're cruisers. The South Pacific, while beautiful and such, is a very harsh environment. Reasonably, what is the life expectancy for the Raymarine equipment that I have installed? I installed most in 2005 or so.
A2. Raymarine does not specify life expectancy for its products. As you have indicated the marine environment can be quite harsh, but varies depending on where one is located.

Q3. A second thought, related to the first, is that since it's all that old, I should buy a completely new suite of equipment and use new networking. I'm sure that it's more stable and much more robust that ST1.
A3. Such choices are quite subjective. However, a prudent mariner will ensure that the electronics which are being relied upon are in good working order, spare are onhand, and that service/parts can be obtained before venturing out on long passages and/or to remote locations where such items are not easily obtained.