Category: Feedlines and Antenna Systems - Canada Radio Amateur Quiz License

Questions in this category:

B-006-001-001: What connects your transceiver to your antenna?
B-006-001-002: The characteristic impedance of a transmission line is determined by the:
B-006-001-003: The characteristic impedance of a 20 metre piece of transmission line is 52 ohms. If 10 metres were cut off, the impedance would be:
B-006-001-004: The characteristic impedance of a coaxial line:
B-006-001-005: What commonly available antenna transmission line can be buried directly in the ground for some distance without adverse effects?
B-006-001-006: The characteristic impedance of a transmission line is:
B-006-001-007: A transmission line differs from an ordinary circuit or network in communications or signalling devices in one very important way. That important aspect is:
B-006-001-008: The characteristic impedance of a parallel wire transmission line does not depend on the:
B-006-001-009: If the impedance terminating a transmission line differs significantly from the characteristic impedance of the line, what will be observed at the input of the line?
B-006-001-010: What factors determine the characteristic impedance of a parallel-conductor antenna transmission line?
B-006-001-011: What factors determine the characteristic impedance of a coaxial antenna transmission line?
B-006-002-001: What is a coaxial cable?
B-006-002-002: What is parallel-conductor transmission line?
B-006-002-003: What kind of antenna transmission line is made of two conductors held apart by insulated rods?
B-006-002-004: What does the term ""balun"" mean?
B-006-002-005: Where would you install a balun to feed a dipole antenna with 50-ohm coaxial cable?
B-006-002-006: What is an unbalanced line?
B-006-002-007: What device can be installed to feed a balanced antenna with an unbalanced transmission line?
B-006-002-008: A flexible coaxial line contains:
B-006-002-009: A balanced transmission line:
B-006-002-010: A 75 ohm transmission line could be matched to the 300 ohm feed point of an antenna:
B-006-002-011: What kind of antenna transmission line can be constructed using two conductors which are maintained a uniform distance apart using insulated spreaders?
B-006-003-001: Why does coaxial cable make a good antenna transmission line?
B-006-003-002: What is the best antenna transmission line to use, if it must be put near grounded metal objects?
B-006-003-003: What are some reasons not to use parallel-conductor transmission line?
B-006-003-004: What common connector type usually joins RG-213 coaxial cable to an HF transceiver?
B-006-003-005: What common connector usually joins a hand-held transceiver to its antenna?
B-006-003-006: Which of these common connectors has the lowest loss at UHF?
B-006-003-007: If you install a 6 metre Yagi on a tower 60 metres (200 ft) from your transmitter, which of the following transmission lines provides the least loss?
B-006-003-008: Why should you regularly clean and tighten all antenna connectors?
B-006-003-009: What commonly available antenna transmission line can be buried directly in the ground for some distance without adverse effects?
B-006-003-010: When antenna transmission lines must be placed near grounded metal objects, which of the following transmission lines should be used?
B-006-003-011: TV twin-lead transmission line can be used for a transmission line in an amateur station. The impedance of this line is approximately:
B-006-004-001: Why should you use only good quality coaxial cable and connectors for a UHF antenna system?
B-006-004-002: What are some reasons to use parallel-conductor transmission line?
B-006-004-003: If your transmitter and antenna are 15 metres (50 ft) apart, but are connected by 60 metres (200 ft) of RG-58 coaxial cable, what should be done to reduce transmission line loss?
B-006-004-004: As the length of a transmission line is changed, what happens to signal loss?
B-006-004-005: As the frequency of a signal is changed, what happens to signal loss in a transmission line?
B-006-004-006: Losses occurring on a transmission line between transmitter and antenna results in:
B-006-004-007: The lowest loss transmission line on HF is:
B-006-004-008: In what values are RF transmission line losses expressed?
B-006-004-009: If the length of coaxial transmission line is increased from 20 metres (66 ft) to 40 metres (132 ft), how would this affect the line loss?
B-006-004-010: If the frequency is increased, how would this affect the loss on a transmission line?
B-006-005-001: What does an SWR reading of 1:1 mean?
B-006-005-002: What does an SWR reading of less than 1.5:1 mean?
B-006-005-003: What kind of SWR reading may mean poor electrical contact between parts of an antenna system?
B-006-005-004: What does a very high SWR reading mean?
B-006-005-005: What does standing-wave ratio mean?
B-006-005-006: If your antenna transmission line gets hot when you are transmitting, what might this mean?
B-006-005-007: If the characteristic impedance of the transmission line does not match the antenna input impedance then:
B-006-005-008: The result of the presence of standing waves on a transmission line is:
B-006-005-009: An SWR meter measures the degree of match between transmission line and antenna by:
B-006-005-010: A resonant antenna having a feed point impedance of 200 ohms is connected to a transmission line which has an impedance of 50 ohms. What will the standing wave ratio of this system be?
B-006-005-011: The type of transmission line best suited to operating at a high standing wave ratio is:
B-006-006-001: What device might allow use of an antenna on a band it was not designed for?
B-006-006-002: What does an antenna tuner do?
B-006-006-003: What would you use to connect a coaxial cable of 50 ohms impedance to an antenna of 17 ohms impedance?
B-006-006-004: When will a power source deliver maximum output to the load?
B-006-006-005: What happens when the impedance of an electrical load is equal to the internal impedance of the power source?
B-006-006-006: Why is impedance matching important?
B-006-006-007: To obtain efficient power transmission from a transmitter to an antenna requires:
B-006-006-008: To obtain efficient transfer of power from a transmitter to an antenna, it is important that there is a:
B-006-006-009: If an antenna is correctly matched to a transmitter, the length of transmission line:
B-006-006-010: The reason that an RF transmission line should be matched at the transmitter end is to:
B-006-006-011: If the centre impedance of a folded dipole is approximately 300 ohms, and you are using RG8U (50 ohms) coaxial lines, what is the ratio required to have the line and the antenna matched?
B-006-007-001: What does horizontal wave polarization mean?
B-006-007-002: What does vertical wave polarization mean?
B-006-007-003: What electromagnetic wave polarization does a Yagi antenna have when its elements are parallel to the Earth's surface?
B-006-007-004: What electromagnetic wave polarization does a half-wavelength antenna have when it is perpendicular to the Earth's surface?
B-006-007-005: Polarization of an antenna is determined by:
B-006-007-006: An isotropic antenna is:
B-006-007-007: What is the antenna radiation pattern for an isotropic radiator?
B-006-007-008: VHF signals from a mobile station using a vertical whip antenna will normally be best received using a:
B-006-007-009: A dipole antenna will emit a vertically polarized wave if it is:
B-006-007-010: If an electromagnetic wave leaves an antenna vertically polarized, it will arrive at the receiving antenna, by ground wave:
B-006-007-011: Compared with a horizontal antenna, a vertical antenna will receive a vertically polarized radio wave:
B-006-008-001: If an antenna is made longer, what happens to its resonant frequency?
B-006-008-002: If an antenna is made shorter, what happens to its resonant frequency?
B-006-008-003: The wavelength for a frequency of 25 MHz is:
B-006-008-004: The velocity of propagation of radio frequency energy in free space is:
B-006-008-005: Adding a series inductance to an antenna would:
B-006-008-006: The resonant frequency of an antenna may be increased by:
B-006-008-007: The speed of a radio wave:
B-006-008-008: At the end of suspended antenna wire, insulators are used. These act to:
B-006-008-009: To lower the resonant frequency of an antenna, the operator should:
B-006-008-010: One solution to multiband operation with a shortened radiator is the ""trap dipole"" or trap vertical. These ""traps"" are actually:
B-006-008-011: The wavelength corresponding to a frequency of 2 MHz is:
B-006-009-001: What is a parasitic beam antenna?
B-006-009-002: How can the bandwidth of a parasitic beam antenna be increased?
B-006-009-003: If a parasitic element slightly shorter than a horizontal dipole antenna is placed parallel to the dipole 0.1 wavelength from it and at the same height, what effect will this have on the antenna's radiation pattern?
B-006-009-004: If a parasitic element slightly longer than a horizontal dipole antenna is placed parallel to the dipole 0.1 wavelength from it and at the same height, what effect will this have on the antenna's radiation pattern?
B-006-009-005: The property of an antenna, which defines the range of frequencies to which it will respond, is called its:
B-006-009-006: Approximately how much gain does a half-wave dipole have over an isotropic radiator?
B-006-009-007: What is meant by antenna gain?
B-006-009-008: What is meant by antenna bandwidth?
B-006-009-009: In free space, what is the radiation characteristic of a half-wave dipole?
B-006-009-010: The gain of an antenna, especially on VHF and above, is quoted in dBi. The ""i"" in this expression stands for:
B-006-009-011: The front-to-back ratio of a beam antenna is:
B-006-010-001: How do you calculate the length in metres (feet) of a quarter-wavelength antenna using frequencies below 30MHz?
B-006-010-002: If you made a quarter-wavelength vertical antenna for 21.125 MHz, approximately how long would it be?
B-006-010-003: If you made a half-wavelength vertical antenna for 223 MHz, approximately how long would it be?
B-006-010-004: Why is a 5/8-wavelength vertical antenna better than a 1/4-wavelength vertical antenna for VHF or UHF mobile operations?
B-006-010-005: If a magnetic-base whip antenna is placed on the roof of a car, in what direction does it send out radio energy?
B-006-010-006: What is an advantage of downward sloping radials on a ground plane antenna?
B-006-010-007: What happens to the feed point impedance of a ground-plane antenna when its radials are changed from horizontal to downward-sloping?
B-006-010-008: Which of the following transmission lines will give the best match to the base of a quarter-wave ground-plane antenna?
B-006-010-009: The main characteristic of a vertical antenna is that it will:
B-006-010-010: Why is a loading coil often used with an HF mobile vertical antenna?
B-006-010-011: What is the main reason why so many VHF base and mobile antennas are 5/8 of a wavelength?
B-006-011-001: How many directly driven elements do most Yagi antennas have?
B-006-011-002: Approximately how long is the driven element of a Yagi antenna for 14.0 MHz?
B-006-011-003: Approximately how long is the director element of a Yagi antenna for 21.1 MHz?
B-006-011-004: Approximately how long is the reflector element of a Yagi antenna for 28.1 MHz?
B-006-011-005: What is one effect of increasing the boom length and adding directors to a Yagi antenna?
B-006-011-006: What are some advantages of a Yagi with wide element spacing?
B-006-011-007: Why is a Yagi antenna often used for radiocommunications on the 20-metre band?
B-006-011-008: What does ""antenna front-to-back ratio"" mean in reference to a Yagi antenna?
B-006-011-009: What is a good way to get maximum performance from a Yagi antenna?
B-006-011-010: The spacing between the elements on a three-element Yagi antenna, representing the best overall choice, is _____ of a wavelength.
B-006-011-011: If the forward gain of a six-element Yagi is about 10 dBi, what would the gain of two of these antennas be if they were ""stacked""?
B-006-012-001: If you made a half-wavelength dipole antenna for 28.150 MHz, approximately how long would it be?
B-006-012-002: What is one disadvantage of a random wire antenna?
B-006-012-003: What is the low angle radiation pattern of an ideal half-wavelength dipole HF antenna in free space installed parallel to the Earth?
B-006-012-004: The impedances in ohms at the feed point of the dipole and folded dipole in free space are, respectively:
B-006-012-005: A horizontal dipole transmitting antenna, installed at an ideal height so that the ends are pointing North/South, radiates:
B-006-012-006: How does the bandwidth of a folded dipole antenna compare with that of a simple dipole antenna?
B-006-012-007: What is a disadvantage of using an antenna equipped with traps?
B-006-012-008: What is an advantage of using a trap antenna?
B-006-012-009: If you were to cut a half wave dipole for 3.75 MHz, what would be its approximate length?
B-006-013-001: What is a cubical quad antenna?
B-006-013-002: What is a delta loop antenna?
B-006-013-003: Approximately how long is each side of a cubical quad antenna driven element for 21.4 MHz?
B-006-013-004: Approximately how long is each side of a cubical quad antenna driven element for 14.3 MHz?
B-006-013-005: Approximately how long is each leg of a symmetrical delta loop antenna driven element for 28.7 MHz?
B-006-013-006: Which statement about two-element delta loops and quad antennas is true?
B-006-013-007: Compared to a dipole antenna, what are the directional radiation characteristics of a cubical quad antenna?
B-006-013-008: Moving the feed point of a multi-element quad antenna from a side parallel to the ground to a side perpendicular to the ground will have what effect?
B-006-013-009: What does the term ""antenna front-to-back ratio"" mean in reference to a delta loop antenna?
B-006-013-010: The cubical ""quad"" or ""quad"" antenna consists of two or more square loops of wire. The driven element has an approximate overall length of:
B-006-013-011: The delta loop antenna consists of two or more triangular structures mounted on a boom. The overall length of the driven element is approximately: