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Canadian Advanced Qualification Question Pool

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A-007-01-01
For an antenna tuner of the "Transformer" type, which of the following statements is FALSE?

The output is suitable for impedances from low to high
The circuit is known as a Pi-type antenna tuner (transmatch)
The circuit is known as a transformertype antenna tuner (transmatch)

A-007-01-02
For an antenna tuner of the "Series" type, which of the following statements is FALSE?

The output is suitable for impedances from low to high
The input is suitable for impedance of 50 ohms
The circuit is known as a Pi-type antenna tuner (transmatch)

A-007-01-03
For an antenna tuner of the "L" type,

The transmitter input is suitable for 50 ohms impedance
The antenna output is high impedance
The circuit is suitable for matching to a vertical groundplane antenna
The circuit is known as an L-type antenna tuner (transmatch)
A-007-01-04
For an antenna tuner of the "Pi" type, which of the following statements is FALSE?

The antenna output is suitable for impedances from low to high
The circuit is a series- type antenna tuner (transmatch)
The circuit is a Pi-type antenna tuner (transmatch)

A-007-01-05
What is a pi-network?

A network consisting of four inductors or four capacitors
A network consisting of one inductor and two capacitors or two inductors and one capacitor
A power incidence network

A-007-01-06
Which type of network offers the greatest transformation ratio?

Butterworth
Pi-network
L-network

A-007-01-07
Why is an L-network of limited utility in impedance matching?

It matches only a small impedance range
It is prone to self-resonance
It has limited power handling capability

A-007-01-08
How does a network transform one impedance to another?

It introduces negative resistance to cancel the resistive part of an impedance
It cancels the reactive part of an impedance and changes the resistive part
Network resistances substitute for load resistances

A-007-01-09
What advantage does a pi-L network have over a pi-network for impedance matching between a vacuum tube linear amplifier and a multiband antenna?

Higher efficiency
Lower losses
Greater transformation range

A-007-01-10
Which type of network provides the greatest harmonic suppression?

Pi-network
Pi-L network
L-network

A-007-01-11
Which three types of networks are most commonly used to match an RF power amplifier to a transmission line?

M, pi and T
L, pi and pi-L
L, M and C

A-007-02-01
What kind of impedance does a quarter wavelength transmission line present to the source when the line is shorted at the far end?

The same as the output impedance of the source
A very high impedance
A very low impedance

A-007-02-02
What kind of impedance does a quarter wavelength transmission line present to the source if the line is open at the far end?

The same as the output impedance of the source
The same as the characteristic impedance of the transmission line
A very low impedance

A-007-02-03
What kind of impedance does a half wavelength transmission line present to the source when the line is open at the far end?

The same as the output impedance of the source
A very high impedance
A very low impedance

A-007-02-04
What kind of impedance does a half wavelength transmission line present to the source when the line is shorted at the far end?

The same as the characteristic impedance of the transmission line
A very low impedance
The same as the output impedance of the source

A-007-02-05
What is the velocity factor of a transmission line?

The index of shielding for coaxial cable
The velocity of the wave on the transmission line divided by the velocity of light
The ratio of the characteristic impedance of the line to the terminating impedance

A-007-02-06
What is the term for the ratio of the actual velocity at which a signal travels through a transmission line to the speed of light in a vacuum?

Surge impedance
Standing wave ratio
Velocity factor

A-007-02-07
What is a typical velocity factor for coaxial cable with polyethylene dielectric?

0.66
0.1
2.7

A-007-02-08
What determines the velocity factor in a transmission line?

The centre conductor resistivity
The terminal impedance
Dielectrics in the line

A-007-02-09
Why is the physical length of a coaxial cable shorter than its electrical length?

Skin effect is less pronounced in the coaxial cable
The characteristic impedance is higher in a parallel feed line
RF energy moves slower along the coaxial cable than in air

A-007-02-10
The reciprocal of the square root of the dielectric constant of the material used to separate the conductors in a transmission line gives the ____________ of the line:

VSWR
impedance
hermetic losses

A-007-02-11
The velocity factor of a transmission line is the:

impedance of the line, e.g. 50 ohm, 75 ohm, etc.
speed at which the signal travels in free space
speed to which the standing waves are reflected back to the transmitter

A-007-03-01
What term describes a method used to match a high-impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places, spaced a fraction of a wavelength on each side of the driven element centre?

The omega match
The stub match
The T match

A-007-03-02
What term describes an unbalanced feed system in which the driven element of an antenna is fed both at the centre and a fraction of a wavelength to one side of centre?

The gamma match
The stub match
The T match

A-007-03-03
What term describes a method of antenna impedance matching that uses a short section of transmission line connected to the antenna feed line near the antenna and perpendicular to the feed line?

The omega match
The delta match
The gamma match

A-007-03-04
What would be the physical length of a typical coaxial stub that is electrically one quarter wavelength long at 14.1 MHz? (Assume a velocity factor of 0.66)

2.33 metres (7.64 feet)
0.25 metre (0.82 foot)
3.51 metres (11.5 feet)

A-007-03-05
The driven element of a Yagi antenna is connected to a coaxial transmission line. The coax braid is connected to the centre of the driven element and the centre conductor is connected to a variable capacitor in series with an adjustable mechanical arrangement on one side of the driven element. The type of matching is:

lambda match
"T" match
zeta match

A-007-03-06
A quarter-wave stub, for use at 15 MHz, is made from a coaxial cable having a velocity factor of 0.8. Its physical length will be:

8 m (26.2 ft)
4 m (13.1 ft)
7.5 m (24.6 ft)

A-007-03-07
The matching of a driven element with a single adjustable mechanical and capacitive arrangement is descriptive of:

a "T" match
an "omega" match
a "Y" match

A-007-03-08
A Yagi antenna uses a gamma match. The coaxial braid connects to:

the variable capacitor
the adjustable gamma rod
the centre of the reflector

A-007-03-09
A Yagi antenna uses a gamma match. The centre of the driven element connects to:

the coaxial line centre conductor
the adjustable gamma rod
a variable capacitor

A-007-03-10
A Yagi antenna uses a gamma match. The adjustable gamma rod connects to:

the variable capacitor
an adjustable point on the reflector
the centre of the driven element

A-007-03-11
A Yagi antenna uses a gamma match. The variable capacitor connects to the:

center of the driven element
coaxial line braid
adjustable gamma rod

A-007-04-01
In a half-wave dipole, the distribution of _______ is highest at each end.

inductance
capacitance
voltage

A-007-04-02
In a half-wave dipole, the distribution of _______ is lowest at each end.

inductance
capacitance
current

A-007-04-03
The feed point in a centre-fed half-wave antenna is at the point of:

maximum current
minimum voltage and current
maximum voltage

A-007-04-04
In a half-wave dipole, the lowest distribution of _________ occurs at the middle.

inductance
current
voltage

A-007-04-05
In a half-wave dipole, the highest distribution of ________ occurs at the middle.

voltage
current
capacity

A-007-04-06
A half-wave dipole antenna is normally fed at the point where:

the voltage is maximum
the resistance is maximum
the antenna is resonant

A-007-04-07
At the ends of a half-wave dipole:

voltage and current are both low
voltage is low and current is high
voltage is high and current is low

A-007-04-08
The impedance of a half-wave antenna at its centre is low, because at this point:

voltage and current are both low
voltage is low and current is high
voltage is high and current is low

A-007-04-09
In a half-wave dipole, where does minimum voltage occur?

It is equal at all points
The centre
Both ends

A-007-04-10
In a half-wave dipole, where does the minimum current occur?

At the centre
It is equal at all points
At the right end

A-007-04-11
In a half-wave dipole, where does the minimum impedance occur?

At the centre
At the right end
At both ends

A-007-05-01
What is meant by circularly polarized electromagnetic waves?

Waves that circle the earth
Waves produced by a circular loop antenna
Waves with a rotating electric field

A-007-05-02
What is the polarization of an electromagnetic wave if its magnetic field is parallel to the surface of the Earth?

Circular
Vertical
Horizontal

A-007-05-03
What is the polarization of an electromagnetic wave if its magnetic field is perpendicular to the surface of the Earth?

Circular
Elliptical
Horizontal

A-007-05-04
The polarization of a radio wave is taken as the direction of the lines of force in the _______ field:

electric
magnetic
electromagnetic

A-007-05-05
A transmitted wave is vertically polarized when:

the antenna is pointing north in the northern hemisphere
the antenna is parallel to the ground
its magnetic component is vertical

A-007-05-06
The polarisation of an antenna is the :

length of the radiating element
radiation angle
orientation of its radiated electric field

A-007-05-07
A parabolic antenna is very efficient because:

no impedance matching is required
a horn-type radiator can be used to trap the received energy
all the received energy is focused to a point where the pick-up antenna is located

A-007-05-08
A helical-beam antenna with right-hand polarization will best receive signals with:

left-hand polarization
vertical polarization only
horizontal polarization

A-007-05-09
One antenna which will respond simultaneously to vertically- and horizontally-polarized signals is the:

folded dipole antenna
ground-plane antenna
quad antenna

A-007-05-10
What precaution should you take whenever you make adjustments to the feed system of a parabolic dish antenna?

Disconnect the antenna- positioning mechanism
Point the dish away from the sun so it doesn't concentrate solar energy on you
Be sure you and the antenna structure are properly grounded

A-007-05-11
Why should a protective fence be placed around the base of a ground-mounted parabolic dish transmitting antenna?

To reduce the possibility that animals will damage the antenna
To increase the property value through increased security awareness
To protect the antenna from lightning damage and provide a good ground system for the installation

A-007-06-01
A transmitter has an output of 100 watts. The cable and connectors have a composite loss of 3 dB, and the antenna has a gain of 6 dB. What is the Effective Radiated Power?

200 watts
400 watts
300 watts

A-007-06-02
As standing wave ratio rises, so does the loss in the transmission line. This is caused by:

high antenna voltage
leakage to ground through the dielectric
dielectric and conductor heat losses

A-007-06-03
What is the Effective Radiated Power of an amateur transmitter, if the transmitter output power is 200 watts, the transmission line loss is 5 watts, and the antenna power gain is 3 dB?

228 watts
178 watts
390 watts

A-007-06-04
Effective Radiated Power means the:

power supplied to the antenna before the modulation of the carrier
power supplied to the feedline plus antenna gain
ratio of signal output power to signal input power

A-007-06-05
A transmitter has an output power of 200 watts. The coaxial and connector losses are 3 dB in total, and the antenna gain is 9 dB. What is the approximate Effective Radiated Power of this system?

1600 watts
800 watts
400 watts

A-007-06-06
A transmitter has a power output of 100 watts. There is a loss of 1.30 dB in the transmission line, a loss of 0.2 dB through the transmatch, and a gain of 4.50 dB in the antenna. The Effective Radiated Power (ERP) is:

400 watts
200 watts
100 watts

A-007-06-07
If the overall gain of an amateur station is increased by 3 dB the ERP (Effective Radiated Power) will:

remain the same
double
be cut in half

A-007-06-08
A transmitter has a power output of 125 watts. There is a loss of 0.8 dB in the transmission line, 0.2 dB in the transmatch, and a gain of 10 dB in the antenna. The Effective Radiated Power (ERP) is:

1125
134
1000

A-007-06-09
If a 3 dB gain antenna is replaced with a 9 dB gain antenna, with no other changes, the Effective Radiated Power (ERP) will increase by:

4
1.5
2

A-007-06-10
A transmitter has an output of 2000 watts PEP. The transmission line, connectors and transmatch have a composite loss of 1 dB, and the gain from the stacked Yagi antenna is 10 dB. What is the Effective Radiated Power (ERP) in watts PEP?

20 000
2009
16 000

A-007-06-11
A transmitter has an output of 1000 watts PEP. The coaxial cable, connectors and transmatch have a composite loss of 1 dB, and the antenna gain is 10 dB. What is the Effective Radiated Power (ERP) in watts PEP?

10 000
8000
9000

A-007-07-01
For a 3-element Yagi antenna with horizontally mounted elements, how does the main lobe takeoff angle vary with height above flat ground?

It increases with increasing height
It does not vary with height
It depends on E-region height, not antenna height

A-007-07-02
Most simple horizontally polarized antennas do not exhibit any directivity unless they are:

a quarter wavelength above the ground
a half wavelength or more above the ground
three-eighths of a wavelength above the ground

A-007-07-03
The plane from which ground reflections can be considered to take place, or the effective ground plane for an antenna is:

depending upon soil conditions
several centimeters to as much as 2 meters below ground, depending upon soil conditions
as much as a meter above ground at ground level exactly

A-007-07-04
Why is a ground-mounted vertical quarter-wave antenna in reasonably open surroundings better for long distance contacts than a half-wave dipole at a quarter wavelength above ground?

The vertical radiation angle is lower
It has an omnidirectional characteristic
It uses vertical polarization

A-007-07-05
When a half-wave dipole antenna is installed one-half wavelength above ground, the:

side lobe radiation is cancelled
radiation pattern is unaffected
vertical or upward radiation is cancelled

A-007-07-06
How does antenna height affect the horizontal (azimuthal) radiation pattern of a horizontal dipole HF antenna?

If the antenna is less than one-half wavelength high, reflected radio waves from the ground significantly distort the pattern
If the antenna is less than one-half wavelength high, radiation off the ends of the wire is eliminated
If the antenna is too high, the pattern becomes unpredictable

A-007-07-07
For long distance propagation, the vertical radiation angle of the energy from the antenna should be:

less than 30 degrees
90 degrees
more than 30 degrees but less than 45 degrees

A-007-07-08
Greater distance can be covered with multiple-hop transmissions by decreasing the:

vertical radiation angle of the antenna
main height of the antenna
length of the antenna

A-007-07-09
The impedance at the centre of a dipole antenna more than 3 wavelengths above ground would be nearest to:

25 ohms
300 ohms
600 ohms

A-007-07-10
What is the main reason why so many VHF base and mobile antennas are 5/8 of a wavelength?

Most of the energy is radiated at a low angle
It's easy to match the antenna to the transmitter
It's a convenient length on VHF

A-007-07-11
The most important consideration when deciding upon an antenna for contacting stations at great distances (DX) is:

sunspot activity
impedance
bandwidth

A-007-08-01
What is meant by the radiation resistance of an antenna?

The specific impedance of an antenna
The combined losses of the antenna elements and feed line
The equivalent resistance that would dissipate the same amount of power as that radiated from an antenna

A-007-08-02
Why would one need to know the radiation resistance of an antenna?

To calculate the front-to-side ratio of the antenna
To match impedances for maximum power transfer
To calculate the front-to-back ratio of the antenna

A-007-08-03
What factors determine the radiation resistance of an antenna?

length/diameter ratio
Transmission line length and antenna height
Sunspot activity and time of day
It is a physical constant and is the same for all antennas
A-007-08-04
What is the term for the ratio of the radiation resistance of an antenna to the total resistance of the system?

Effective Radiated Power
Radiation conversion loss
Antenna efficiency

A-007-08-05
What is included in the total resistance of an antenna system?

Radiation resistance plus ohmic resistance
Transmission line resistance plus radiation resistance
Radiation resistance plus space impedance

A-007-08-06
How can the approximate beamwidth of a beam antenna be determined?

Note the two points where the signal strength is down 3 dB from the maximum signal point and compute the angular difference
Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna

A-007-08-07
How is antenna percent efficiency calculated?

(total resistance / radiation resistance) X 100
(effective radiated power / transmitter output) X 100
(radiation resistance / total resistance) X 100

A-007-08-08
What is the term used for an equivalent resistance which would dissipate the same amount of energy as that radiated from an antenna?

"j" factor
Antenna resistance
"K" factor

A-007-08-09
Antenna beamwidth is the angular distance between :

the maximum lobe spread points on the major lobe
the 6 dB power points on the major lobe
the 3 dB power points on the first minor lobe

A-007-08-10
If the ohmic resistance of a half-wave dipole is 2 ohms, and the radiation resistance is 72 ohms, what is the antenna efficiency?

72%
97.3%
100%

A-007-08-11
If the ohmic resistance of a miniloop antenna is 2 milliohms and the radiation resistance is 50 milliohms, what is the antenna efficiency?

96.15%
25%
50%

A-007-09-01
Waveguide is typically used:

at frequencies above 1500 MHz
at frequencies below 150 MHz
at frequencies below 1500 MHz

A-007-09-02
Which of the following is NOT CORRECT? Waveguide is an efficient transmission medium because it features :

low dielectric loss
low hysteresis loss
low copper loss

A-007-09-03
Which of the following is an advantage of waveguide as a transmission line?

Low loss
Expensive
Heavy and difficult to install

A-007-09-04
For rectangular waveguide to transfer energy, the cross- section should be at least:

one-eighth wavelength
one-half wavelength
one-quarter wavelength

A-007-09-05
Which of the following statements about waveguide IS NOT correct?

Waveguide has high loss at high frequencies, but low loss below cutoff frequency
In the transverse magnetic mode, a component of the electric field is in the direction of propagation
Waveguide has low loss at high frequencies, but high loss below cutoff frequency

A-007-09-06
Which of the following is a major advantage of waveguide over coaxial cable for use at microwave frequencies?

Easy to install
Very low losses
Inexpensive to install

A-007-09-07
What is printed circuit transmission line called?

Microstripline
Dielectric imprinting
Ground plane

A-007-09-08
Compared with coaxial cable, microstripline:

has superior shielding
must have much lower characteristic impedance
must have much higher characteristic impedance

A-007-09-09
A section of waveguide:

operates like a band-stop filter
is lightweight and easy to install
operates like a high-pass filter

A-007-09-10
Microstripline is:

a high power microwave antenna
a family of fluids for removing coatings from small parts
printed circuit transmission line

A-007-09-11
What precautions should you take before beginning repairs on a microwave feed horn or waveguide?

Be sure the transmitter is turned off and the power source is disconnected
Be sure propagation conditions are unfavorable for tropospheric ducting
Be sure to wear tight-fitting clothes and gloves to protect your body and hands from sharp edges

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