Page 63
Flymaster GPS M User Manual v. 1.0
at which the GPS M will start buzzing. For example with the GPS M default values, Climb
threshold=0.1m/s, and Buzzer=3 (0.3m/s) the buzzing with start at -0.2m/s because 0.1 - 0.3= -0.2.
In this case at 0.1m/s directly below the Climb threshold the GPS M will emit a constant sound
varying rapidly in pitch from around 100hz to the set base frequency at which the first beep is
emitted. This is the buzzer sound and may resemble a growl noise.
Setting the Buzzer value to O
˙ will disable the buzzer feature.
Although the Buzzer will sound very annoying on the ground it becomes an amazing companion in
flight allowing the pilot to pick-up thermals he would have usually missed
A practical example of the advantages of the buzzer feature can be illustrated in Figure bellow In
this example both pilots are sinking at -1.0 m/s. The orange paraglider has a GPS M for which the
climbing threshold is set to 0.1 m/s and the Buzzer parameter is set to 3 (0.3 m/s). The green
paraglider has a typical vario for which the climbing threshold is set to 0.1 m/s.
As shown in the figure, when both pilots enter the thermal nothing is heard. The air is rising at 0.1
m/s but both pilots are descending at -0.9 m/s. In the second zone of the thermal the air is rising at
0.8 m/s, and so pilots are descending at -0.2 m/s. At this stage the orange pilot starts to hear the
Buzzer brrrrr sound of his GPS M , which helps him to centre the thermal, while the green pilot is
still unaware of the thermal. Finally, in the 3 zone, the air is rising at 1.2 m/s, and so both pilots
climb at 0.2 m/s. The GPS M pilot starts to hear his vario beep... beep... sound, and it is only at this
point the green pilot hears the first beep from his instrument.
Damper -
The GPS M 's vertical speed calculation is based on air pressure variations. It is very
seldom to have air pressure absolutely stable. Turbulence caused by air moving near the sensor
is sufficient to cause small variations in pressure. For this reason the GPS M filters (averages) the
pressure data to prevent constantly detecting tiny pressure variations. The value that defines how
must the pressure is filtered is the Damper. Setting a lower damper value caused the GPS M to
become more responsive but harsher. Inversely a higher value causes the GPS M to be less
responsive but smoother. The default value is 6.
Dynamic Frequency-
The GPS M beeps at a specified pitch (frequency) when a certain rate
of climb is encountered. When dynamic frequency is zero, the pitch (frequency) of that beep will
remain constant if the rate of climb changes. With dynamic frequency on, the pitch of the beep may
vary if the rate of climb varies during the individual beep.
