Garmin GNC 420AW Pilot's Manual page 10

Part One: Section 1
TIS Operation and Symbology
The TIS audio alert is generated from the
GTX 330 whenever the number of Traffic Ad-
visories on the 400W/500W display increases
from one scan to the next. Limiting Traffic
Advisories only reduces the "nuisance" alerting
due to proximate aircraft. For example, when
the first Traffic Advisories appears on the TIS
display, the user is alerted audibly. So long as
a single aircraft remains on the TIS display, no
further audio alert is generated. If a second (or
more) aircraft appears on the display, a new
audio alert is sounded.
If the number of Traffic Advisories on the TIS
display decreases and then increases, a new
audio alert is sounded. The TIS audio alert is
also generated whenever TIS service becomes
unavailable. The volume, pitch, and duration
of the audio alert (including the choice between
a male or female voice) is configured during
installation.
The following TIS audio alerts are available:
• "Traffic" —TIS traffic alert is received.
• "Traffic Not Available" — TIS service is not
available or out of range.
4
Traffic Advisory (TA)—This symbol is generated when traffic
meets the advisory criteria described in TIS Operational Proce-
Traffic Ground Track is indicated
on the 400W/500W display by a
"target track vector", a short line
displayed in 45-degree increments.
This vector shows the flight direc-
tion of the traffic.
190-00356-30 Rev H
dures.
"Other" Traffic—This symbol represents
traffic detected within the selected display
range that does not generate a TA.
Own Aircraft