V7 Version 1.96
Januar 2012
Page 20 of 39
The electronic TE compensation can be fine-tuned during flight using the following
procedure: it is essential that this is only done in smooth air; it is not possible to tune the
TE accurately in turbulent air.
Set TE compensation to 100%. Accelerate up to approximately 160 km/h (75 kts) and keep
the speed stable for a few seconds. Gently reduce the speed to 80 km/h (45 kts). Observe
the vario indicator during the manoeuvre. At 160 km/h the vario will indicate about –2 m/s
(-4 kts). During the speed reduction the vario should move towards zero and should never
exceed zero (slightly positive indications are acceptable). If the vario shows a climb the
compensation is too low; increase the TE%; and vice versa. Try another “zoom” to assess
the change and make further adjustments if necessary.
Electronic TE compensation is only effective when the pitot tube and static sources are co-
located and the pneumatic lines to the instrument are approximately the same length. The
best sensor to use is the combined pitot/static Prandtl tube. If problems are experienced
with the electronic TE compensation the most likely cause is the glider's static source. The
static source can be checked by plumbing the pneumatic tubes for electronic compensation
and then setting the TE: to 0%. In still air accelerate to approximately 160 km/h and slowly
reduce the speed. Observe the vario indicator. If the static source is good the vario should
immediately start to move to show a climb. If the needle firstly shows increased sink and
then moves to a climb, the static source of the glider is unsuitable and there is no way to
provide successful TE compensation electronically. The use of a dedicated and accurate fin-
mounted pitot/static source such as a Prandtl tube might help.
5.3.3.11
Temperature Offset
The LXNAV V7 is supplied with an external outside air temperature (OAT) sensor. With the
offset setting it will correct static errors of temperature measurement.
5.3.4
Sounds
In the Sounds setup menu audio settings for the LXNAV V7 and alarms settings can be
modified.
5.3.4.1
Vario Volume
The sounds slider changes the audio volume.
Summary of Contents for V7
Page 2: ......