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BENDIX/KING
KT 73
Rev 0, October/2002
10563I00.JA
Page 3-15
3.3.2
FRONT PANEL OPERATION
Refer to figure 3-1 for an illustration relating to front panel operation.
IDT (IDENT):
The KT 73’s Ident pushbutton (marked IDT) is pressed when the ground control requests an
“Ident” or “Squawk Ident” from the aircraft.
x
An input pin is located on the rear connector for an external ident pushbutton.
x
The external and front panel IDENT operate identically in all applicable modes of operation.
x
The SPI pulse is not be transmitted when replying to Mode C interrogations.
(a)
On/Altitude Mode
Depressing the "IDT" momentary contact switch while in the ON or ALTITUDE
mode:
1.
will cause the special position identification pulse (SPI) to be
appended to Mode A replies for a period of 18
±
1 seconds.
2.
will be reflected in the Flight Status field of Mode S downlink
format 4 and 5 replies for a period of 18
±
1 seconds.
3.
will cause the unit to display the "IDT" nomenclature for a
period of 18
±
1 seconds.
4.
will be reflected in the ME field of Mode S downlink 17 for a
period of 18
±
1 seconds.
(b)
Ground Mode
Depressing the "IDT" momentary contact switch while in the GROUND mode:
1.
will cause the special position identification pulse (SPI) to be
reflected in the Flight Status field of Mode S downlink format
4 AND 5 replies to discretely addressed Mode S interroga-
tions for a period of 18
±
1 seconds.
2.
will cause the unit to display the "IDT" nomenclature for a
period of 18
±
1 seconds.
4096 ID CODE:
x
While in the Standby, Ground, On, or Altitude modes, the 4096 code is displayed in the IDENT
window on the right side of the display.
x
Modification of the 4096 code is performed via the VFR push button or four Transponder Code
Selector Knobs. Each knob selects a separate digit of the identification code.
x
The 4096 Identification code digits range from 0 to 7.
(a)
Code Entry
Upon entering a 4096 code:
1.
The new 4096 ID code will be stored in EEPROM 3.5
±
0.5
seconds after the entry is completed.
2.
The new 4096 ID code will be transmitted 3.5
±
0.5 seconds
after the entry is completed.
3.
If the "IDT" push-button is depressed, the chosen code will
be immediately stored in EEPROM and transmitted along
with the appropriate Mode A SPI pulse in response to a
Mode A interrogation.
Impress Tryout
Preliminary - Subject To Change Without Notice