JSK
New member
Can anyone tell me if the Nasa fluxgate steering compass has a NMEA output that would be suitable to connect to my radar,If not what make would be suitable and at best price?
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NASA COMPASS
- Thread starter JSK
- Start date
Jools_of_Top_Cat
New member
Most RADAR especially if you want to drive ARPA or MARPA will require 10Hz output on the NMEA bus. The NASA compass only kicks out 2Hz. But it also appears that raymarines seatalk is 2Hz, so a little confusion,
The NASA compass will work but update on the RADAR may be slow, Raymarines Q&A on this subject suggest it might cause problems on tight turns etc. well if you are a saily type this might not be a problem. And if you use their propriety system seatalk it is limited to 2Hz anyhow from their own instruments.
If this makes any sense to you, you will be where I am now, I am trying to find a compass for my RADAR and trying to pin down definate answers is not easy. I quite like the look of the raymarine ST40 over the clipper because it has seatalk, but, as have just said, this seems limited to 2Hz, so I might as well match my instruents and get the NASA unit.
Oh the joy. I have found some great looking units that seem perfect for the job, but they tend to be in the £500.00 area!
I also had some corresponence with nasamarine who asked if there is enough of a market for them to update the fluxgate compass sender to 10Hz and sell as a stand alone for people who want to use with their RADAR's. This is a really competetively priced unit and would mean not having to have the head unit, which is the way I would like to go. I do not know what size market nasa would need to change the specs on their units!
<hr width=100% size=1>J
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The NASA compass will work but update on the RADAR may be slow, Raymarines Q&A on this subject suggest it might cause problems on tight turns etc. well if you are a saily type this might not be a problem. And if you use their propriety system seatalk it is limited to 2Hz anyhow from their own instruments.
If this makes any sense to you, you will be where I am now, I am trying to find a compass for my RADAR and trying to pin down definate answers is not easy. I quite like the look of the raymarine ST40 over the clipper because it has seatalk, but, as have just said, this seems limited to 2Hz, so I might as well match my instruents and get the NASA unit.
Oh the joy. I have found some great looking units that seem perfect for the job, but they tend to be in the £500.00 area!
I also had some corresponence with nasamarine who asked if there is enough of a market for them to update the fluxgate compass sender to 10Hz and sell as a stand alone for people who want to use with their RADAR's. This is a really competetively priced unit and would mean not having to have the head unit, which is the way I would like to go. I do not know what size market nasa would need to change the specs on their units!
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Oldhand
New member
Not sure if a straight fluxgate compass upgraded to 10Hz output would give you much of an improvement without the inclusion of solid state rate "gyro" sensors and software to reduce errors from motion in a seaway and sluggishness due to dip. Thats why the heading sensors recommended for ARPA or MARPA are £500+.
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JSK
New member
Many thanks Jools you certainly seemed to have researched the subject.Am i right in thinking that I do not need the display head only the sender? The only reason I need a fluxgate compasss is to run the JRC1500 on the north up setting,I have the Autohelm 4000 but this i am told does not have NMEA out.
Thanking you again JSK
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Thanking you again JSK
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Jools_of_Top_Cat
New member
Has anyone used marpa without spending 50% of the initial radar cost on compass equipment. Is anyone having success or limited success just using an output from an autopilot or standard non gyro nmea compass.
I would really like to know if the unit would be unusable for marpa, I hear a lot of you should have this, and you should definately have that. But I would like to know if anyone ignored this and has been able to maintain acceptable results from a standard compass.
Many thanks in anticipation.
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I would really like to know if the unit would be unusable for marpa, I hear a lot of you should have this, and you should definately have that. But I would like to know if anyone ignored this and has been able to maintain acceptable results from a standard compass.
Many thanks in anticipation.
<hr width=100% size=1>J
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