Table 5-6 Key Lighting Selections; Table 5-7 Key Source Selections - Garmin GTX 330 Installation Manual

KEY (Key Lighting)
SELECTION
AUTO (Automatic)
MAN (Manual)
LVL (Level)
Shows the current level of key lighting, based on the lighting input source (lighting bus voltage, or the
ambient light if the source is PHOTO) and the settings on this configuration page. This field has a range of
0 (zero) to 999, but is not a user-entered field (display only).
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 0 to 7, and
is set to 4 at the factory.
MIN (Minimum) (Auto Only)
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) (Auto Only)
SELECTION
PHOTO (Photocell)
14V
28V
5V
SLOPE (Auto Only)
Sets the sensitivity of the key lighting brightness to changes in the input level. The higher the number, the
brighter the key lighting 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 (Auto Only)
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.
190-00207-02
Rev. U

Table 5-6 Key Lighting Selections

Key lighting is automatically controlled based on the parameters entered on
this configuration page.
Key lighting is controlled manually by the pilot on the GTX 330 DISPLAY
page.

Table 5-7 Key Source Selections

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
DESCRIPTION
GTX 330/330D Installation Manual
Page 5-9