Flymaster GPS LS User Manual page 17

10.2 Advanced settings
UNIT - Sets the GPS LS units to Metric or Imperial units.
UTC - Using GPS data, the GPS LS automatically adjusts the internal clock
to the Universal Coordinated Time (UTC). The user should adjust the UTC
offset so that the time displayed by the GPS LS matches the
local time.
CTRS - Sets the contrast of the display.
SLTN - Setting Auto silent option ON will keep the GPS LS 's sound quiet
until a Start Flight has been detected. This function avoids listening the
vario sound while waiting to take off. The audio will then be kept active
until the GPS LS is switched off. The default value for the auto silent
parameter is ON.
To set the start speed to allow start you track log and to start the vario
sound:
1 - Connect your GPS LS , turned ON, to the Designer software:
1.1 - Click on instrument's logo and choose "instrument settings"
1.2 - On the tab "logger" choose your start speed.