On Wednesday, February 13, 2013 11:33:57 PM UTC+2, John Galloway wrote:
At 17:34 13 February 2013, waremark wrote:

What I have read on this forum has led me to think that the

Butterfly is

currently a decent vario in operation but nothing special. Can

anyone with

practical experience say different?



I surmise that the software engineers have not yet discovered

what to do

with all the data available to them.



Since my LX 9000 has the optional giro box what data would it

not have that

would potentially make the Butterfly better?



The very alluring Butterfly vario is using the sensor data but the

concern that has stopped me choosing it so far is the

importance for its performance of getting an accurate reading

from the magnetometer. It is inside the main sensor box which

has all the electrical and pneumatic connections and that makes

it awkward to mount in a way that meets the installation

manual's specifications for distance from electromagnetic field

interference - especially in a retractable motor glider. Two

friends have returned them because theye were unable to

achieve this.



I have the same worry about getting the similarly configured CN

vario for the same reason - although it doesn't matter at

present while the magnetometer is not used (AFAIK).



The LX 9000 AHRS unit has "3 axis Gyros with MEMS technology

and 3 axis digital +-6g accelerometer" according to the

website. If the separate LX 9000 compass module is 3-axis(??)

then including that along with the GPS in the 9000 and the

pneumatic sensors from the V5 vario would appear to make it

match the sensor mix of the Butterfly. Whether they could all

be integrated to work as a full intertial sensor unit I have no

idea - nor whether LX Nav have any plan to try to make it do

so. The fact that the magnetometer is a separate box should

make it easier to locate away from interference.



John Galloway

I thought exactly same about placement of Butterfly IMU. Separate magnetometer would be more convenient, as you have to route GPS antenna, three pneumatic tubes and CAN-bus to the box. AFAIK succesful installation requires quite a distance from *everything*. BTW common radio speakers don't have any magnetic shielding around speaker magnet, for some reason. Strong magnets can disturb compass as far as 1,5 metres away...