TM 55-1510-219-10
Figure 3-25. Transponder Control Panel (AN/APX - 100)
MASTER
Selects system operating mode.
CONTROL
OFF
Deactivates system.
STBY
Activates system warm-up
(standby) mode.
NORM
Activates normal operating
mode.
EMER
Transmits emergency reply code.
STATUS ANT
Illuminates to indicate the BIT
indicator
or MON fault is caused by high
VSWR in antenna.
STATUS KIT
Illuminates to indicate the BIT
indicator
or MON fault is caused by exter-
nal computer.
STATUS ALT
Illuminates to indicate BIT or
indicator
MON fault is caused by to Alti-
tude Digitizer.
IDENT MIC
Selects source of aircraft identi-
switch
fication signal.
IDENT
Activates transmission of identi-
fication (IP) pulse.
MIC
Enables either control wheel
POS IDENT switch to activate
transmission of ident signal
from transponder.
MODE 4 reply
Illuminates to indicate a reply
indicator
has been made to a valid Mode
4 interrogation.
MODE 4
Selects monitor mode for Mode
AUDIO OUT
4 operation.
switch
AUDIO
Enables sound and sight moni-
toring of Mode 4 operation.
LIGHT
Enables monitoring REPLY in-
dicator for mode 4 operation.
OUT
Deactivates monitor mode.
MODE 3/A code
Select desired reply codes for
selectors
Mode 3/A operation.
MODE 1 code
Select desired reply codes for
selectors
Mode 1 operation.
MODE
4 TEST Selects test mode of Mode 4
OUT switch
operation.
TEST
Activates built-in-test of Mode 4
operation.
ON
Activates mode 4 operation.
OUT
Disables Mode 4 operation.
MODE 4 code
Selects preset Mode 4 code.
control
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