Garmin GTX 330 Installation Manual page 44

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.
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Rev E
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.
GTX 330 Installation Manual
190-00207-02