n2k Heading True Derived Data
Hi all!
Im getting N2k via the YDWG-02 dongle. It seems Iām not getting "Heading True" which is needed for the Derived-Data in order to calculate TWA & TWS. Im getting Heading True from the NEMA 0183 connection, but I only want to use N2K.
According to the YDWG-02 manual YDWG-02 NMEA 2000 --> NMEA 0183 converter is able to calculate True Heading. Magnetic variation is used in RMC, HDT, HDG, VDR, VHW, VTG. Priority of variation PGNs: 127250, 127258, 65311
I have a hard time understanding what to do with the above so was wondering if Derived Data or another plug can calculate Heading True?
maybe @Scott Bender has an idea?
17 Replies
I don't understand the bit about 0183 conversion
The YDWG-02 does not do 0183 conversion
If you don't have a device on the network that sends True Heading, then the YDWG-02 won't provide it
You can use derived data to calculate true heading from magentic
got it. I have an ev 100 with the P70, I assume one of those can send True Heading in the 0183 connection.
But its really perfect if I can use derived data to calculate True Heading.
Any pointers how to do that?
I hace the ev100 does not send out true heading
just use the dervived data plugin to calculate it
it's a very simple calculation and it is exatly what the the ev100 would do if it sent it
the Raymarine MFDs used to calculate it and send it out, but they not implement that in Lighthouse 3/4
that requires navigation.magneticVariation, which the Raymarine MFDs do send out
you can provide a default value to use if the MFD is off
hmm, i dont have an MDF,
only P70, St60 wind and tridata + a older Garmin Gpsmap
the image shows the 0183 conection
anyway, lets see if ia can solve it with dervived data.
Do you have an example/suggestion how to do the calculation?
I just hardcode navigation.magneticVariation in defaults, it never changes for me
so navigation.magneticVariation = navigation.headingTrue š
no, that is used by derived-data to calculate headingTrue
Not my strongest part but do I get it right if
1. Signal K outputs navigation.magneticVariation (seems my NK2 network supplies this)
2. Then use derived-data calculate headingTrue from navigation.magneticVariation and ?
3. Whats the derived-data calculation ?
all you have to do is add navigation.magneticVariation to defaults, and enable the true heading calculation in derived-data
for #3 did you want me to show you the math?
ahh, no. I thought i needed to build the calculation myself and add it to Derived Data
it's there already
got it
thanks, will see if i can set it all up with a simulator plug in at home
š
GitHub
FAQ: Frequently Asked Questions
An implementation of a Signal K central server for boats. - SignalK/signalk-server
^^^^^ how to add magneticVariation as static data
hah, even has navigation.magneticVariation as an example
yeah saw it š
ill just copy it
got it all working! Thanks alot for the support!
ur welcome!