Garmin GTX 330 Installation Manual page 35

RSP TIME (Response Time)
Sets the speed with which the brightness responds to ambient light changes (only for AUTO key lighting mode). The
higher the number, the slower the key lighting responds. This field has a range of 3 to 7, and is set to 4 at the factory.
MIN (Minimum)
Sets the minimum brightness of the key lighting. The higher the number, the brighter the minimum brightness. Key
lighting minimum brightness has a range of 0 (zero) to 99, and is set to 8 at the factory. It is prudent to verify that
key lighting characteristics match those of other equipment in the aircraft panel under night lighting conditions.
KEY SRCE (Key Lighting Source)
Selection
PHOTO (Photocell)
14V
28V
5V
SLOPE
Sets the sensitivity of the key lighting brightness to changes in the input level. The higher the number, the brighter
the key lighting will be for a given increase in the input level. This field has a range of 0 (zero) to 99, and is set to 50
at the factory.
OFFSET
Adjusts the key lighting level up or down for any given input level. This field has a range of 0 (zero) to 99, and is set
to 50 at the factory. This may also be used to match lighting curves with other equipment in the panel.
5.2.7 CONTRAST MODE Page
CONTRAST MODE
Selection
MAN (Manual)
AUTO (Automatic)
CONTRAST LEVEL ADJUSTMENT
This is a "slider" bar graph control. Use the 8 key to move the graph to the left, decreasing the numbers and contrast
level. Use the 9 key to move it to the right, increasing the numbers and contrast level. It is set to 50% at the factory.
In manual contrast mode, this is a direct adjustment of the display contrast. In automatic contrast mode, this adjusts
the offset to the automatically compensated contrast.
Page 5-8
Rev. 1
Description
DEFAULT. Key lighting level is determined by the ambient light
level as measured by the photocell on the GTX 330.
Backlight level tracks a 14 volt DC aircraft lighting bus.
Backlight level tracks a 28 volt DC aircraft lighting bus.
Backlight level tracks a 5 volt DC aircraft lighting bus.
Description
The display contrast is manually adjusted either here or by the pilot
using the GTX 330 CONTRAST page.
DEFAULT. The display contrast is automatically compensated for
temperature and other factors. An offset can be entered in the contrast
level adjustment described below.
CONTRAST Page
GTX 330 Installation Manual
190-00207-02