Renschler CoMo AV - Track and Northpointer; SOG (Speed over Ground) and Windanalysis

2.8.5 Track and Northpointer
To define a track the GPS has to be moved horizontally by a
speed of at least 1.5 km/h whether you are flying or walking.
Remember: This is not as responsive as a magnetic compass!
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2.8.6 SOG (Speed over Ground) and Windanalysis
When GPS has found a position, the speed display shows speed
over ground (SOG). As SOG is a horizontal movement only, climb
and descend-rates have no influence at all on its value. The SOG-
display lets you judge the wind situation, as it is a compound of
air-speed and wind-speed. Flying with tail-wind adds values,
while flying with head-wind subtracts wind-speed from air-speed.
Example: if the SOG is 60 km/h in one direction and in the
opposite direction only 20 km/h, then you travel at 40 km/h
while wind velocity is 20 km/h.
Warning: Never try to judge wind-direction close to ground just
by watching your SOG! Valley winds, thermals etc., may totally
alter the wind direction and speed in a chosen landing area.
Better to rely on the good old trusty windsock or natural indicators
(smoke, a rustle in a cornfield, ripples on a lake´s surface, etc.)!
flight-direction
track
north
indication only from 1,5 km/h on!