A flashing bar under the mode in the upper right hand corner of the display is the STX 165’s reply
annunciator. It will blink at a 1 Hz rate whenever the STX 165 is replying to interrogations ground or
TCAS interrogations.
Pressure Altitude, Density Altitude, Outside Air Temperature
The STX 165 will display PALT in the lower right quadrant of the display. This quadrant can also
display Density Altitude (DALT) and Outside Air Temperature (OAT) if the optional
SANDIA aero-
space
STP 78 OAT probe is installed. Upon initial turn on the PALT display will be blanked until the
transducer hearter has come up to temperature. Depending upon the ambient air temperature, this can
take up to a minimum one minute.
Note: If the optional STP 78 OAT probe is not installed only Pressure Altitude
(PALT) will be displayed in the lower right quadrant.
Timer Functions
The STX 165 has three timer functions that are displayed in the lower left display quadrant. To select
the desired timer, rotate the SELECT knob twice clockwise or once counterclockwise. The turn the
DATA knob to select the desired Timer function.
Elapsed Flight Time
(EFT) begins counting when the unit is powered up or reaches a preset AGL
altitude that is programmed by the pilot in the user set up mode. The EFT is not resettable after power
up. The EFT counts in minutes and seconds up to 59 minutes and 59 seconds and then begins counting
in hours and minutes.
Note: The TIMER UP counts in Minutes and Seconds for 59 minutes and 59 sec-
onds and then displays time in hours and minutes
.
Caution: If the computed altitude is out of range the PALT display will show -9982
feet. If there is an altitude failure the PALT display will show -9981. Note that
neither of these are valid altitudes in the normal mode.
7
To display the alternate functions in the lower right quanrant, turn the SELECT knob once in the
closckwise direction. The displayed data in the lower right quadrant will blink.Turn the DATA knob
until the data you want displyed is visable. Then press the ENTER pushbutton. If the ENTER push-
button is not pressed within 15 seconds the display will revert to the previous information.
