User's Manual

VTU-3 Users Guide
Page 10 of 18
LoJack Confidential Proprietary
Document Not To Be Copied Or Retransmitted In Any Form Without Prior Authorization
When the menu is in the “Brightness” (B) mode it can be manual or automatic; in
automatic mode, the intensity of the display will be changed by the amount of ambient
light falling on the display unit. The brighter the ambient light the higher the display
intensity will go, the lower the ambient light the lower the intensity will go. This feature is
provided to eliminate the need for an operator to adjust the display while traveling through
different ambient light environments.
The different “Brightness” operating modes (manual or automatic) can be identified by an
indication next to the “B” in the menu portion of the screen. If there are three lines “=“ next
to the “B” (i.e., “B=”), the display is in the “Brightness Manual” mode, otherwise it is in the
“Brightness Automatic” mode (i.e., “B”).
When in either the “Brightness” or “Volume” mode the first press of an Up or Down
control button will switch the screen to display, a level indicator for the mode activity on the
lower left side of the screen as shown in Figure 4. When the Auto mode is entered the
level indicator will be replaced by the word “AUTO”
When the menu is in the “Brightness Manual” (B=) mode each press of the “Up” arrow will
increase the brightness to the limit and will then switch to the auto mode, another button
press will return to the manual mode, go to the lowest brightness level and begin to
increase again. See Figure 3 for a diagram of the button actions. The “Down” arrow will
cycle to the lowest brightness level then switch to the auto mode, another button press will
return to the manual mode, go to the brightness level detected by the auto mode and
begin to decrease again.
The Brightness control operates the same in both directions of travel, i.e., it wraps around
in both directions 8,7,6,5,4,3,2,1,AUTO,8,7,6,5,4,··· and 1,2,3,4,5,6,7,8,AUTO,1,2,···
Figure 3 VTU3 Brightness Control Actions
Pressing either the up or down button while in automatic mode will switch into the manual
brightness mode.