TCAS791
Operating Instructions
Pilot’s Guide
2-3
Table 2-1. Controls and Indicators (Continued)
No
Description
7
Altitude Display Mode Indicator
On the CD605, this indicator displays the currently selected altitude
display mode: ABV (above, or look up), BLW (below, or look
down), or NRM (normal).
Some alternate displays do not display the NRM indicator. Other
alternate displays do not display any altitude display mode
indicators because they do not support any altitude display modes
other than normal.
In the above display mode, traffic detected 9,000 ft and
–2,700 ft of your aircraft is displayed. In the below display mode,
traffic 2,700 ft and –9,000 ft of your aircraft is displayed.
In the normal display mode, traffic detected within ±2,700 ft of
your aircraft is displayed.
8
Test Button
The test button is on the front of the CD605. If you’re using an
alternate display, a discrete button in the cockpit serves as the test
button. If you are using the CD605 with an alternate display, you
can use both test buttons.
The avionics dimming input from your aircraft controls the
brightness of the light inside the test button on the CD605.
Pressing the test button when in standby starts a TCAS791 self test.
Pressing the test button repeatedly when not in standby toggles the
altitude display mode in the following order: above, normal, below,
normal, above, etc. (Repeatedly pressing the test button with an
alternate display that does not support the above and below display
modes has no effect.)
Pressing and holding the test button when in standby will run the
test, and if the test passes, will hold the test screen on the CD605 or
the final test screen on an alternate display. When you release the
button, the display will go back to its standby screen. Holding the
test button in will not hold the test screen on the display if the test
fails. In this case, the CD605 goes to its TCAS FAILED screen and
the alternate display goes to its TCAS FAIL screen or to its standby
screen, depending on the display model.
