Radio Principles

Question 1

what is frequency?

Answer 1

rate of recurrence of a vibration, oscillation or cycle.`

Question 2

what is CPS?

Answer 2

Cycles per second

Question 3

What is 1 CPS equal to in Hertz?

Answer 3

1 CPS = 1 Hertz

Question 4

What is 1,000 CPS equal to in Hertz?

Answer 4

1,000CPS = 1,000 Hz or 1 Kilohertz (KHz)

Question 5

What is 1,000,000 CPS equal to in Hertz?

Answer 5

1,000,000 = 1,000 KHz or 1 Megahertz (MHz)

Question 6

what allows radio waves to travel through space and most materials?

Answer 6

due to their electric/magnetic field status

Question 7

Is distance covered by sound waves greater than radio?

Answer 7

No

Question 8

How fast do Radio Waves travel?

Answer 8

Speed of light

Question 9

what does HF stand for?

Answer 9

High Frequency

Question 10

What is the HF range?

Answer 10

3 - 30 MHz

Question 11

What does VHF stand for?

Answer 11

Very High Frequency

Question 12

what is the VHF range?

Answer 12

30 - 300 MHz

Question 13

which frequency is preferred for long-distance and the other for Aviation?

Answer 13

HF = long
VHF = aviation

Question 14

why is VHF used for aviation?

Answer 14

because the greater amount of frequencies within the band, allow for a great range of available frequencies in support of the numbers of services required.

Question 15

Why is the reception of VHF comms superior to HF?

Answer 15

due to the lower frequencies being more prone to interference from various sources, e.g atmospheric disturbances

Question 16

what are the disadvantages to VHF?

Answer 16

the inability of signets to bend around objects such as mountains.

Question 17

What are transmissions referred to as?

Answer 17

Line of sight

Question 18

why are transmissions referred as it is?

Answer 18

because of the disadvantages of VHF

Question 19

In terms of comms what are most aircraft fitted with?

Answer 19

handheld and boom mics with handheld substituting as a 1backup.

Question 20

FM or AM for microphones?

Answer 20

FM normally

Question 21

What is squelch control?

Answer 21

a control used to eliminate unwanted signals such as static

Question 22

When is squelch control used?

Answer 22

when flying towards the limit of reception, can be fixed by adjusting the squelch control knob to the position of where extraneous noise is minimised.

Question 23

What is the RADIO NOT WORKING simple fault finding procedure process? (8)

Answer 23

• Check master switch and optionally avionics master is ON
• Check radio ON?OFF set to ON and with NAV/COM set, make sure proper side is on (NAV side ON instead of COM)
• Check correct settings on the audio selector panel if fitted.
• Check circuit breakers or fuses.
• Check all connections such as microphone plug, and if using headphones check if they’re plugged in properly
• Check correct frequency has been selected and double-check the frequency set to COM.
• Check volume control is up
• Check squelch control is not fully anti-clockwise.p

Question 24

What are the additional radio equipment in aircraft?

Answer 24

two additional radios, ELT and the Transponder

Question 25

What is a transponder?

Answer 25

a device for receiving a radio signal and automatically transmitting a different signal

Question 26

what allows transponders to do?

Answer 26

allow for a ground-based radar controller to determine the location and sometimes altitude of aircraft.

Question 27

What can the info off transponders do?

Answer 27

Can be obtained by pilots with an Airbourne Collision Avoidance System (ACAS) to ascertain the position of other aircraft equipped with transponders.

Question 28

what is TM?

Answer 28

Transponder Mandatory Zone.

Question 29

What does TM require?

Answer 29

require aircraft to be equipped with a functioning transponder.

Question 30

what happens if an aircraft doesn’t have a transponder equipped in a TM?

Answer 30

maybe permitted by ATC in certain situations and must append the words “NEGATIVE TRANSPONDER” to the request.

Question 31

How is Transponder Mandatory Zones identified on NZ visual aeronautical charts?

Answer 31

by the letters TM.`

Question 32

On the NZ visual aeronautical chart if it shows a box with:

• A Captial C
• 2500 / SFC
• WN 118.8
• TM

What do they mean?

Answer 32

C = Class C Airspace
2500 / SFC = Surface - 2500 Feet Uncontrolled since its a Class C Airspace
WN 118.8 = Wellington 118.8 Frequency
TM = Transponder Mandatory Zone.

Question 33

What do OFF, ON, SBY(Standby), ALT(Altitude), and TST mean on transponders?

Answer 33

OFF = transponder off
SBY = Stand-by, transponder on, but won't reply
ON = transponder on and will reply to interrogation but only Mode A info.
ALT = transponder on and will reply, both info sent. Can see altitude and position.
TST = Transponder Test Function.

Question 34

What are the 3 important emergency codes?

Answer 34

7500, 7600, 7700

Question 35

What does 7500 mean?

Answer 35

Unlawful interference (Hijacking) 75 let the other guy drive

Question 36

What does 7600 mean?

Answer 36

Comms failure, 76 Radio needs a fix

Question 37

what does 7700 mean?

Answer 37

emergency (Distress) 77 pray to heaven.

Question 38

what does SQUAWK IDENT mean?

Answer 38

must press transponder ident button once, allows controller to identify aircraft.