IFF(2018)

Question 1

What does the acronym IFF stands for?

Answer 1

Identification Friend or Foe.

Question 2

What are the three basic steps in the iden- tification process of a typical IFF system?

Answer 2

Challenge, decode, and reply.

Question 3

True or False. All naval aircraft contain an interrogator system.

Answer 3

False.

Question 4

What is the pulse spacing of Mode 1?

Answer 4

2.9 to 3.1 micro seconds.

Question 5

Of the six modes of IFF operation, which one is used by military and civilian aircraft control stations?

Answer 5

Mode 3/A.

Question 6

What mode IFF is the military encrypted mode?

Answer 6

Mode 4.

Question 7

What is the transmission frequency of the interrogator?

Answer 7

1030 MHz.

Question 8

In a typical IFF/SIF system, what total number of codes can be selected in Mode 2?

Answer 8

4,096.

Question 9

The Identification of Position (I/P) pulse is used for what purpose?

Answer 9

It is used to identify a specific friendly aircraft among other friendly aircraft that reply with the same code.

Question 10

What mode of IFF is set prior to takeoff by maintenance personnel?

Answer 10

Mode 2.

Question 11

Where are Modes 1 and 3/A selected on the AN/APX-72 transponder set?

Answer 11

By thumbwheel switches on the front of the control box.

Question 12

What part of the APX-72 system provides for ground or in-flight transponder testing capability?

Answer 12

The Transponder Test Set TS-1843/APX.

Question 13

The AN/APX-72 generates a signal of what frequency when interrogated?

Answer 13

1090 MHz.

Question 14

The interrogator works in conjunction with what other aircraft system?

Answer 14

The radar.

Question 15

What component of the interrogator set is used to select SIF reply codes for Modes 1, 2, and 3/A?

Answer 15

C-7383/APX-76(V) control box.

Question 16

What component monitors the timing triggers, pre-triggers, gates, and test video and causes the fault indicator lamp on the interrogator control to illuminate when a fault has been detected within the system?

Answer 16

Electronic Synchronizer SN-416/APX-76(V).

Question 17

The APX-100 transponder set is available in what number of configurations?

Answer 17

The system comes in two configurations.

Question 18

To respond to Mode 4 interrogations, the IFF transponder set system requires what addi- tional components?

Answer 18

Transponder Computer KIT-1/TSEC.

Question 19

What APX-100 system is referred to as the rack-mounted configuration?

Answer 19

Receiver/Transmitter RT-1157/APX-100.

Question 20

What electronic circuit compares both videos
in the AN/APX-100 system to determine the
stronger signal?

Answer 20

Diversity processor

Question 21

What number of major configurations exist for

the AN/APX-100 system?

Answer 21

Two

Question 22

The AN/APX-100 system contains what number
of antenna(s)?

Answer 22

Two

Question 23

The interrogator set works in conjunction with

which of the following systems?

Answer 23

Radar

Question 24

What component of the interrogator set contains
performance monitoring circuits that perform
self-tests during each challenging period?

Answer 24

Switch Amplifier SA-1568/APX-76(V)

Question 25

What component of the interrogator set determines the delay between the challenge pulse and receipt of the coded replies for determining target range?

Answer 25

Receiver/Transmitter RT-868/APX-76(V)

Question 26

Which of the following components of the APX-72 system allow the transponder to respond to Mode 4 interrogations?

Answer 26

KIT-1/TSEC

Question 27

Which of the following APX-72 system components provides for ground or in-flight transponder testing capability?

Answer 27

TS-1843/APX

Question 28

Which of the following components of the APX-72 system contains controls for selection of Modes 1 and 3/A?

Answer 28

C-6280/APX-72

Question 29

When is the SPI pulse present in the reply pulse | train in Mode C?

Answer 29

When a D4 pulse is present

Question 30

The X-pulse special reply function is used for | which of the following purposes?

Answer 30

Unmanned or experimental aircraft

Question 31

The I/P function is used for which of the | following purposes?

Answer 31

Aircraft using identical coding

Question 32

The emergency function affects which of the | following IFF mode(s)?

Answer 32

1, 2, and 3/A

Question 33

Mode 4 codes are loaded into the transponder | computer by which of the following means?

Answer 33

Electronically

Question 34

Which of the following IFF codes are set prior | to flight by maintenance personnel?

Answer 34

2 and 4

Question 35

What is the total number of possible codes | available in Mode C IFF?

Answer 35

2048

Question 36

In a typical IFF system, what total number of combinations of codes can be selected in Mode 1?

Answer 36

32

Question 37

In a typical IFF system, what total number of combinations of codes can be selected in Mode C?

Answer 37

2048

Question 38

Astandard SIF reply is bound by a total of how | many framing pulse(s)?

Answer 38

Two

Question 39

What is the transmission frequency of the | transponder?

Answer 39

1090 MHz

Question 40

What is the pulse spacing of Mode 1?

Answer 40

2.9 to 3.1 μs

Question 41

What is the pulse spacing of Mode 2?

Answer 41

4.8 to 5.2 μs

Question 42

What is the pulse spacing of Mode 3/A?

Answer 42

7.8 to 8.2 μs

Question 43

Which of the following modes are used strictly by the military as tactical modes for mission and identification purposes?

Answer 43

1 and 2

Question 44

What it the transmission frequency of the | interrogator?

Answer 44

1030 MHz

Question 45

Which of the following modes of IFF operation | is the military encrypted mode?

Answer 45

Mode 4

Question 46

What IFF mode of operation is used to report | altitude information?

Answer 46

Mode C

Question 47

In a typical IFF system, what component is | referred to as the responding unit?

Answer 47

The transponder

Question 48

In a typical IFF system, what component is | referred to as the challenging unit?

Answer 48

The interrogator