How to get True Wind Direction instead of apparent using Signal K.

[PaddyB]

Thank you so much for this, I will try that out tomorrow. 
My windsensor is already outputting wind angle 0-359 degrees in to Signal K, I just thought it would be possible to just forward that, or prevent the recalculation to Apparent wind angle.
I realiize Signal K is used for boating and that's why my problem is probably not relevant for this software.

You can do the same calibration in grafana , add a math function in select >>