Subsection 10 Fibre Optics

Question 1

A ‘ Remote terminal’ on a MIL-STD-1773 fibre optic network is?

Answer 1

The devices being controlled

Question 2

A ‘ Type A ‘ fibre optic connector would be used for connections?

Answer 2

Not regularly disconnected

Question 3

A disadvantage of a fibre optic cable is end terminals are?

Answer 3

Susceptible to environmental contamination

Question 4

A fibre optic coupler is used to distribute the optical signal from one fibre among two or more fibres or to combine the optical signal from two or more fibres into a?

Answer 4

single fibre

Question 5

A fibre optic ‘ T ‘ coupling is?

Answer 5

2 or more sources into 1 output

Question 6

A fibre optic cable consists of a silica glass core with a cladding having?

Answer 6

A lower refractive index

Question 7

A Fibre optic cable that has been fitted with too tight a bend radius will suffer from?

Answer 7

Attenuation and loss of signal

Question 8

A Fibreoptic data bus used on an aircraft can transmit on?

Answer 8

Several channels at the same time

Question 9

A fibreoptic cable to the LRU connector should be connected?

Answer 9

Very carefully to ensure alignment and reduce light loss

Question 10

A fibreoptic lens type coupling with lens and integral LED compared to an end-fibre coupling is?

Answer 10

More efficient

Question 11

A fibreoptic light source is normally a?

Answer 11

laser or LED

Question 12

A remote terminal can be connected to a network by ?

Answer 12

Conventional copper cables or fibre optic cables

Question 13

A remote terminal in a fibre optic network syatem requires?

Answer 13

A microprocessor

Question 14

A semiconductor which emits photons and releases electrons when stimulated is called?

Answer 14

A Laser diode

Question 15

A silica glass fibre optic cable is more refractive in the?

Answer 15

Middle

Question 16

A typical fibre optic connector is?

Answer 16

Coupling type with lens fitted

Question 17

A typical wavelength of light in an optical fibre is?

Answer 17

1300nm

Question 18

An advantage of fibreoptic cables over conventional cable is that?

Answer 18

It offers greater security

Question 19

Common aircraft fibreoptics use?

Answer 19

Modulating intensity on direct read

Question 20

Continuit of a fibreoptic cable is checked by?

Answer 20

A calibrated light source and an opto-power meter

Question 21

Fibre optic cables are immune to?

Answer 21

EMI

Question 22

Fibre optic data is sent by?

Answer 22

A strobe light

Question 23

Fibre optic cables use?

Answer 23

A refractive outer shell

Question 24

Fibre optic systems can transmit data in?

Answer 24

Both directions at the same time

Question 25

Fibreoptics relies on?

Answer 25

Light reflecting off cladding

Question 26

For a fibroptic cable connector that is not regularly disconnected you would use?

Answer 26

The Butt type

Question 27

For a fibreoptic to function, then the refractive index of the core must be?

Answer 27

Greater than for the cladding

Question 28

For a fibreoptic cable system that requires frequent disconnection and reconnection of the cable, one type of connector suitable is a?

Answer 28

Micro lens

Question 29

For high bandwidth highspeed fibreoptic transmission, what sort of cable would you use?

Answer 29

Singe mode

Question 30

For total internal reflection to occur, the angle of incidence must be?

Answer 30

Greater than the critical angle

Question 31

HIRF is prevented from entering a fibre optic cable by using?

Answer 31

An opto-isolator coupling

Question 32

In fibre optic network systems, what device handles management duties such as operation. administration and maintenance?

Answer 32

Remote control terminal

Question 33

In a fibreoptic cable, multiple data signals ?

Answer 33

Can be sent down it at one time

Question 34

In a singe mode fobre optic cable, the diameter of the cable is dependant on?

Answer 34

The wavelength of the light used

Question 35

In an optical fibre half duplex data transmission, data is transferred?

Answer 35

Both ways, one way at a time

Question 36

In an optical fibre simplex data transmission, data is transferred?

Answer 36

In one direction only

Question 37

In an optical fibre, the angle of acceptance is?

Answer 37

Half the cone of acceptance

Question 38

In a fibreoptic cable, signals are seperated by?

Answer 38

An active optic filter

Question 39

In fibreoptics the wave length of the light is?

Answer 39

More than visible light

Question 40

Light transmission in a fibreoptic cable is due to?

Answer 40

Repeated internal reflection

Question 41

Light travels along a fibre optic by?

Answer 41

Reflection

Question 42

Most fibroptic connectors are designed so the connections can?

Answer 42

Not be overtightened

Question 43

Optical coherant transmissions use a single mode laser with?

Answer 43

Send and receive opto-isolators

Question 44

Optical fibre losses are due to?

Answer 44

Absorption, scattering and reflection

Question 45

Passive sensors in fibreoptics, process the signal but?

Answer 45

Do not require power

Question 46

Sensors in a fibroptic flight control system require?

Answer 46

Power for the processors

Question 47

Some of the advantages of fibroptic cable over copper cables are?

Answer 47

Smaller in size and weight, non-conductive, higher security and higher bandwidth

Question 48

The speed of light in a fibre optic cable is?

Answer 48

Never greater than the speed of light in free space

Question 49

Star couplers are used in fibre optic systems for?

Answer 49

Equally distributing signals to equipment

Question 50

The angle of acceptance for fibre optics is the ?

Answer 50

Maximum angle to accept light into the core for transmission

Question 51

The angle of incidence of a beam of light in a fibreoptic cable will be?

Answer 51

Approximately half that of the cone

Question 52

The central controlling terminal of a fibre optic network is the?

Answer 52

Network control terminal

Question 53

The fibreoptic cable can be identified on aircraft by its jacket colour which is?

Answer 53

Purple

Question 54

The cone of acceptance is measured between?

Answer 54

The longitudinal axis of the core and the outer angle

Question 55

The light source used in fibreoptics is?

Answer 55

Lower bandwidth than visible light

Question 56

The name given to the joining of two fibroptic cables by aligning them carefully and bringing them into close proximity of each other is?

Answer 56

End to End

Question 57

The power inputs to a star coupler are?

Answer 57

More than two

Question 58

Two connected fibre optic cable ends are parallel but not quite touching, this is called?

Answer 58

End fire coupling

Question 59

What does a fibreoptic star connection do?

Answer 59

Provides direct point-to-point services to units on dedicated lines emanating from the central hub

Question 60

What is the advantage of a laser diode over an LED?

Answer 60

Narrower bandwidth

Question 61

What is the advantage of a single mode fibreoptic over ordinary wire?

Answer 61

Large bandwidth

Question 62

What is the advantage of an ILD over an LED when used as a light source in fibre optics?

Answer 62

Lower frequency range

Question 63

What is the main cause of attenuation in fibreoptics?

Answer 63

Poor termination

Question 64

What is the main disadvantage of a fibre optic data bus?

Answer 64

Expensive to install

Question 65

What kind of light is used in a fibre optic system?

Answer 65

Infared

Question 66

What maintenance problems are associated with fibreoptics?

Answer 66

Kinking and contamination of connectors

Question 67

When using a TDR ( time delay reflectometer ) the loss of value of the cable is shown by?

Answer 67

The curve on the screen

Question 68

Which of the following databus specifications is suitable for fibreoptic communications on aircraft?

Answer 68

ARINC 664

Question 69

Which of the following is an optoelectronic device?

Answer 69

Laser diode.