Compare Meteostick vs Davis Envoy

[assenzuid]

I'm testing an seperate Meteobridge setup with a Meteostick and I see some difference in the values, especially the wind reading.
The Meteostick always jumps from 0.0ms to 0.5ms and the Davis Envoy reads 0.4ms or 0.5ms

Both reading the same data from there respectively transmitters (Anemometer Transmitter kit)
See attachment.

[admin]

How did you make sure it is data from exactly the same point in time?
I don't know how long it takes until data the envoy reads from the sensors
via RF is reflected in a loop packet transported to the PC.

[assenzuid]

Simultaneously pressing the Live button.
Every 2.5 seconds the Davis Anemometer Transmitter Kit (6332) send its date to the VP2 Console and Envoy (at both I see the same values)
The Meteobridge with Meteostick only jumps from 0.0ms reading always to 0.5ms and the the VP2 Console and Envoy shows 0.4ms.

Also I see that the Wind direction is not accurate/correct. I have tuned the Metebridge setup with the Meteostick with Wind Direction correction of -6.

The most beautiful of the Meteostick is the reading of the additional leaf/soil transmitter. It shows now the correct temperature without the 0.5 degree steps as on the VP2 Console and Envoy.

[admin]

Regarding wind direction there are some new findings that can bring Meteostick even closer to the console readings, if 6 degrees count at all

[assenzuid]

Ok, but why the meteostick has some different readings then my Davis VP2 console and Envoy logger (without any changes, only aligned the Anemometer preciously to the North)

[admin]

This is because some sensors don't report data as displayed on console, but as raw values that need
further treatment. As Davis does not make their formulas public, any 3rd party solution
has to find a suitable formula by their ow. By collecting a large array of different data pretty good
approximations can be found, but they might not match what the console shows in the very last decimal.
For temperature I can say that it is in +/- 0.2 degrees Celsius bounds compared to console,
which is better than the precision the sensors and their calibration does ever provide.

Regarding wind direction the sensor has a dead spot which Davis software covers by a cheat,
as some guys in the wxforum discovered. When I replicate this cheating to Meteostick
firmware as well, number should be identical in 1 degree bounds. But again, don't get fixated
to numbers to that extend. It is completely uninteresting if wind direction is 178 or 183 degrees, imho.
One number is as right or wrong as the other and both tell me that wind was coming pretty straight
from the south, which of course is interesting.

[assenzuid]

Thanks for the clarification

Last weekend I did a simply test. I pointed my anemometer to the north (taped).
The Davis console and Envoy reported it as 360 degree which is correct according the Davis Manual, also my Meteobridge with the connected Envoy reported this value.
The Meteobridge with the connected Meteostick reported it as 0 degree.