twistedtree
Guru
Calling all Simrad Radar owners. I've got some time on my Simrad package now and am having some troubling problems with the radar and am wondering if others are seeing the same issues.
1) Probably the most troubling is that MARPA works poorly. To best illustrate the problem, I picked out a boat with AIS, then also locked onto it as a MARPA target. Within some margin of error the AIS course/speed predictor on MARPA should match the AIS course/speed line. It doesn't, but is instead off by 10-20 degrees. I have also verified this against the trail of dots that the radar leaves showing the path of the boat, and against the course of boats in controlled shipping lanes where their course is both known and constant.
2) The MARPA course/speed predictor bounces all over the place the more movement there is in by boat. It's like it's not compensating for my boat's movement even though I have heave, pitch, and roll sensors in the Sat compass
3) The CU (course up) setting does not work. The radar can be set to HU, CU, or NU. When set to CU, the radar shows "CU" on the display, but continues to orient the display and compass rose based on the heading, not the COG. In cross current, this can be a big difference and further confuses the whole issue of the course predictor lines and what they mean.
By way of a little more background, and to answer what I'm sure will be the first wave of questions, here's some more info.
- I have two Simrad Radars on the boat. One is a 10KW open array, and the other is 4G. I get the same behavior from both radars.
- Both radars report that they have a valid heading source and the MARPA status is good.
- I have two different heading sources and have tried both with the same results. One is an HS70 Sat Compass that is a combination GPS and heading sensor and is supposed to be the ultimate in heading accuracy. It also reports pitch, roll, heave, etc. As backup I have a regular GPS and an RC42 rate compass. It's easy to switch between the two, and I get the same results both ways. I have also completely disconnected the HS70 to no avail.
- Display of the radar info is via a Simrad NSO black box running the latest SW. All components in the system have been updated to the vendors latest release.
Anybody else using MARPA and how does it work?
1) Probably the most troubling is that MARPA works poorly. To best illustrate the problem, I picked out a boat with AIS, then also locked onto it as a MARPA target. Within some margin of error the AIS course/speed predictor on MARPA should match the AIS course/speed line. It doesn't, but is instead off by 10-20 degrees. I have also verified this against the trail of dots that the radar leaves showing the path of the boat, and against the course of boats in controlled shipping lanes where their course is both known and constant.
2) The MARPA course/speed predictor bounces all over the place the more movement there is in by boat. It's like it's not compensating for my boat's movement even though I have heave, pitch, and roll sensors in the Sat compass
3) The CU (course up) setting does not work. The radar can be set to HU, CU, or NU. When set to CU, the radar shows "CU" on the display, but continues to orient the display and compass rose based on the heading, not the COG. In cross current, this can be a big difference and further confuses the whole issue of the course predictor lines and what they mean.
By way of a little more background, and to answer what I'm sure will be the first wave of questions, here's some more info.
- I have two Simrad Radars on the boat. One is a 10KW open array, and the other is 4G. I get the same behavior from both radars.
- Both radars report that they have a valid heading source and the MARPA status is good.
- I have two different heading sources and have tried both with the same results. One is an HS70 Sat Compass that is a combination GPS and heading sensor and is supposed to be the ultimate in heading accuracy. It also reports pitch, roll, heave, etc. As backup I have a regular GPS and an RC42 rate compass. It's easy to switch between the two, and I get the same results both ways. I have also completely disconnected the HS70 to no avail.
- Display of the radar info is via a Simrad NSO black box running the latest SW. All components in the system have been updated to the vendors latest release.
Anybody else using MARPA and how does it work?