Safety First
Basic Qualification Question Bank for Amateur Radio Operator Certificate Examinations 12 June, 2014
Physiology
(B)
B-003-018-005 How little electrical current flowing through the human body can be fatal?
A Current flow through the human body is never fatal
B As little as 20 milliamperes
C Approximately 10 amperes
D More than 20 amperes
(B)
B-003-018-006 Which body organ can be fatally affected by a very small amount of electrical current?
A The lungs
B The heart
C The brain
D The liver
(C)
B-003-018-007 What is the minimum voltage which is usually dangerous to humans?
A 1000 volts
B 2000 volts
C 30 volts
D 100 volts
In an Emergency
(D)
B-003-018-008 What should you do if you discover someone who is being burned by high voltage?
A Wait for a few minutes to see if the person can get away from the high voltage on their own, then try to help
B Immediately drag the person away from the high voltage
C Run from the area so you won't be burned too
D Turn off the power, call for emergency help and provide first-aid if needed
(D)
B-003-018-009 What is the safest method to remove an unconscious person from contact with a high voltage source?
A Wrap the person in a blanket and pull him to a safe area
B Call an electrician
C Remove the person by pulling an arm or a leg
D Turn off the high voltage switch before removing the person from contact with the source
Electrical Isolation
(D)
B-003-018-010 Before checking a fault in a mains operated power supply unit, it would be safest to first:
A short out leads of filter capacitor
B check action of capacitor bleeder resistance
C remove and check fuse from power supply
D turn off the power and remove power plug
(C)
B-003-018-011 Fault finding in a power supply of an amateur transmitter while the supply is operating is not a recommended technique because of the risk of:
A overmodulation
B blowing the fuse
C electric shock
D damaging the transmitter
(A)
B-003-020-010 What safety precautions should you take before beginning repairs on an antenna?
A Be sure to turn off the transmitter and disconnect the transmission line
B Be sure you and the antenna structure are grounded
C Inform your neighbours so they are aware of your intentions
D Turn off the main power switch in your house
Limit of Approach
(C)
B-003-018-004 Why would there be a switch in a high-voltage power supply to turn off the power if its cabinet is opened?
A To keep dangerous RF radiation from coming in through an open cabinet
B To turn the power supply off when it is not being used
C To keep anyone opening the cabinet from getting shocked by dangerous high voltages
D To keep dangerous RF radiation from leaking out through an open cabinet
(B)
B-003-020-006 For safety, how high should you place a horizontal wire antenna?
A As close to the ground as possible
B High enough so that no one can touch any part of it from the ground
C Above high-voltage electrical lines
D Just high enough so you can easily reach it for adjustments or repairs
(A)
B-003-020-008 Why should your outside antennas be high enough so that no one can touch them while you are transmitting?
A Touching the antenna might cause RF burns
B Touching the antenna might reflect the signal back to the transmitter and cause damage
C Touching the antenna might radiate harmonics
D Touching the antenna might cause television interference
(C)
B-003-020-009 Why should you make sure that no one can touch an open wire transmission line while you are transmitting with it?
A Because contact might cause spurious emissions
B Because contact might cause a short circuit and damage the transmitter
C Because high-voltage radio energy might burn the person
D Because contact might break the transmission line
(D)
B-003-020-011 What precaution should you take when installing a ground-mounted antenna?
A It should be painted so people or animals do not accidentally run into it
B It should not be installed in a wet area
C It should not be installed higher than you can reach
D It should be installed so no one can come in contact with it
(D)
B-003-021-011 For best RF safety, where should the ends and center of a dipole antenna be located?
A Near or over moist ground so RF energy will be radiated away from the ground
B As close to the transmitter as possible so RF energy will be concentrated near the transmitter
C Close to the ground so simple adjustments can be easily made without climbing a ladder
D As high as possible to prevent people from coming in contact with the antenna
Station Grounding
(D)
B-003-019-001 For best protection from electrical shock, what should be grounded in an amateur station?
A The antenna transmission line
B The AC power line
C The power supply primary
D All station equipment
(C)
B-003-019-002 If a separate ground system is not possible for your amateur station, an alternative indoor grounding point could be:
A a window screen
B a metallic natural gas pipe
C a metallic cold water pipe
D a plastic cold water pipe
(D)
B-003-019-003 To protect you against electrical shock, the chassis of each piece of your station equipment should be connected to:
A a dummy load
B insulated shock mounts
C the antenna
D a good ground connection
(B)
B-003-019-004 Which of these materials is best for a ground rod driven into the earth?
A Fiberglass
B Copper-clad steel
C Hard plastic
D Iron or steel
(B)
B-003-019-005 If you ground your station equipment to a ground rod driven into the earth, what is the shortest length the rod should be?
A 3 metres(10 ft)
B The station ground system must conform to applicable electrical code requirements
C 1.2 metre(4 ft)
D 2.5 metres(8 ft)
(A) Where should the green wire in a three-wire AC line cord be connected in a power supply?
A To the chassis
B To the white wire
C To the "hot" side of the power switch
D To the fuse
(D)
B-003-019-007 If your third-floor amateur station has a ground wire running 10 metres(33 feet) down to a ground rod, why might you get an RF burn if you touch the front panel of your HF transceiver?
A Because of a bad antenna connection, allowing the RF energy to take an easier path out of the transceiver through you
B Because the transceiver's heat-sensing circuit is not working to start the cooling fan
C Because the ground rod is not making good contact with moist earth
D Because the ground wire has significant reactance and acts more like an antenna than an RF ground connection
(C)
B-003-019-008 What is one good way to avoid stray RF energy in your amateur station?
A Drive the ground rod at least 4m(14 feet) into the ground
B Use a beryllium ground wire for best conductivity
C Keep the station's ground wire as short as possible
D Make a couple of loops in the ground wire where it connects to your station
(B)
B-003-019-009 Which statement about station grounding is true?
A The chassis of each piece of station equipment should be tied together with high-impedance conductors
B RF hot spots can occur in a station located above the ground floor if the equipment is grounded by a long ground wire
C A ground loop is an effective way to ground station equipment
D If the chassis of all station equipment is connected with a good conductor, there is no need to tie them to an earth ground
(C)
B-003-019-010 On mains operated power supplies, the ground wire should be connected to the metal chassis of the power supply. This ensures, in case there is a fault in the power supply, that the chassis:
A becomes conductive to prevent electric shock
B develops a high voltage compared to the ground
C does not develop a high voltage with respect to the ground
D does not become conductive to prevent electric shock
(A)
B-003-019-011 The purpose of using a three-wire power cord and plug on amateur radio equipment is to:
A prevent the chassis from becoming live
B prevent the plug from being reversed in the wall outlet
C prevent internal short circuits
D make it inconvenient to use
(A)
B-003-020-001 Why should you ground all antenna and rotator cables when your amateur station is not in use?
A To help protect the station equipment and building from lightning damage
B To lock the antenna system in one position
C To avoid radio frequency interference
D To make sure everything will stay in place
Lightning Protection
(B)
B-003-020-002 You want to install a lightning arrestor on your antenna transmission line, where should it be inserted?
A Anywhere on the line
B Outside, as close to earth grounding as possible
C Close to the antenna
D Behind the transceiver
(D)
B-003-020-003 How can amateur station equipment best be protected from lightning damage?
A Use heavy insulation on the wiring
B Never turn off the equipment
C Disconnect the ground system from all radios
D Disconnect all equipment from the power lines and antenna cables
Working at Heights
(C)
B-003-020-004 What equipment should be worn for working on an antenna tower?
A A flashing red, yellow or white light
B A grounding chain
C Approved equipment in accordance with applicable standards concerning fall protection
D A reflective vest of approved colour
(B)
B-003-020-005 Why should you wear approved fall arrest equipment if you are working on an antenna tower?
A To safely hold your tools so they don't fall and injure someone on the ground
B To prevent you from accidentally falling
C To safely bring any tools you might use up and down the tower
D To keep the tower from becoming unbalanced while you are working
(A)
B-003-020-007 Why should you wear a hard hat if you are on the ground helping someone work on an antenna tower?
A To protect your head from something dropped from the tower
B So you won't be hurt if the tower should accidentally fall
C To keep RF energy away from your head during antenna testing
D So someone passing by will know that work is being done on the tower and will stay away
Safety Code 6
(C)
B-001-024-001 What organization has published safety guidelines for the maximum limits of RF energy near the human body?
A Environment Canada
B Transport Canada
C Health Canada
D Canadian Standards Association
(D)
B-001-024-002 What is the purpose of the Safety Code 6?
A It lists all RF frequency allocations for interference protection
B It sets transmitter power limits for interference protection
C It sets antenna height limits for aircraft protection
D It gives RF exposure limits for the human body
(B)
B-001-024-003 According to Safety Code 6, what frequencies cause us the greatest risk from RF energy?
A 3 to 30 MHz
B 30 to 300 MHz
C 300 to 3000 MHz
D Above 1500 MHz
(B)
B-001-024-004 Why is the limit of exposure to RF the lowest in the frequency range of 30 MHz to 300 MHz, according to Safety Code 6?
A Most transmissions in this range are for a longer time
B The human body absorbs RF energy the most in this range
C There are more transmitters operating in this range
D There are fewer transmitters operating in this range
(D)
B-001-024-005 According to Safety Code 6, what is the maximum safe power output to the antenna of a hand-held VHF or UHF radio?
A 10 watts
B 25 watts
C 125 milliwatts
D Not specified
(A)
B-001-024-006 Which of the following statements is not correct?
A Permissible exposure levels of RF fields decreases as frequency is decreased below 10 MHz
B Maximum exposure levels of RF fields to the general population, in the frequency range 10 to 300 MHz, is 28 V/m RMS(E-field)
C Permissible exposure levels of RF fields increases as frequency is increased from 300 MHz to 1.5 GHz
D Permissible exposure levels of RF fields increases as frequency is decreased from 10 MHz to 1 MHz
(C)
B-001-024-007 The permissible exposure levels of RF fields:
A increases, as frequency is increased from 10 MHz to 300 MHz
B decreases, as frequency is increased above 300 MHz
C increases, as frequency is increased from 300 MHz to 1.5 GHz
D decreases, as frequency is decreased below 10 MHz
(D)
B-001-024-008 Which statement is not correct?
A Antenna gain, distance, transmitter power and frequency are all factors which influence the electric field strength and a person's exposure to radio energy.
B Safety Code 6 uses different units for the magnetic field strength and the electric field strength when stating limits
C Safety Code 6 specifies lower exposure limits for the general public in uncontrolled areas than it does for people in controlled areas
D hand held transmitters are excluded from Safety Code 6 requirements
(B)
B-001-024-009 Which statement is correct?
A Portable transmitters, operating below 1 GHz, with an output power equal to, or less than 7 watts, are exempt from the requirements of Safety Code 6
B Safety Code 6 sets limits for RF exposure from all radio transmitters regardless of power output
C Safety Code 6 regulates the operation of receivers only
D The operation of portable transmitting equipment is of no concern in Safety Code 6
(C)
B-001-024-010 Which of these statements about Safety Code 6 is false?
A Safety Code 6 sets limits for induced currents, electrical field strength and magnetic field strength from electromagnetic radiation
B Safety Code 6 sets limits for allowable rates at which RF energy is absorbed in the body(Specific Absorption Rate)
C Safety Code 6 sets limits in terms of power levels fed into antennas
D Safety Code 6 sets limits for contact currents that could be drawn from ungrounded or poorly grounded objects
(C)
B-003-021-001 What should you do for safety when operating at UHF and microwave frequencies?
A Make sure the standing wave ratio is low before you conduct a test
B Never use a horizontally polarized antenna
C Keep antenna away from your eyes when RF is applied
D Make sure that an RF leakage filter is installed at the antenna feed point
(D)
B-003-021-002 What should you do for safety if you put up a UHF transmitting antenna?
A Make sure the antenna is near the ground to keep its RF energy pointing in the correct direction
B Make sure you connect an RF leakage filter at the antenna feed point
C Make sure that RF field screens are in place
D Make sure the antenna will be in a place where no one can get near it when you are transmitting
(B)
B-003-021-003 What should you do for safety, before removing the shielding on a UHF power amplifier?
A Make sure all RF screens are in place at the antenna transmission line
B Make sure the amplifier cannot accidentally be turned on
C Make sure that RF leakage filters are connected
D Make sure the antenna transmission line is properly grounded
(D)
B-003-021-004 Why should you make sure the antenna of a hand-held transceiver is not close to your head when transmitting?
A To use your body to reflect the signal in one direction
B To keep static charges from building up
C To help the antenna radiate energy equally in all directions
D To reduce your exposure to the radio-frequency energy
(B)
B-003-021-005 How should you position the antenna of a hand-held transceiver while you are transmitting?
A Pointed down to bounce the signal off the ground
B Away from your head and away from others
C Pointed towards the station you are contacting
D Pointed away from the station you are contacting
(D)
B-003-021-006 How can exposure to a large amount of RF energy affect body tissue?
A It lowers blood pressure
B It paralyzes the tissue
C It causes hair to fall out
D It heats the tissue
(C)
B-003-021-007 Which body organ is the most likely to be damaged from the heating effects of RF radiation?
A Liver
B Hands
C Eyes
D Heart
(D)
B-003-021-008 Depending on the wavelength of the signal, the energy density of the RF field, and other factors, in what way can RF energy affect body tissue?
A It causes ionizing radiation poisoning
B It causes blood flow to stop
C It has no effect on the body
D It heats the tissue
(D)
B-003-021-009 If you operate your amateur station with indoor antennas, what precautions should you take when you install them?
A Position the antennas parallel to electrical power wires to take advantage of parasitic effects
B Position the antennas along the edge of a wall where it meets the floor or ceiling to reduce parasitic radiation
C Locate the antennas close to your operating position to minimize transmission line length
D Locate the antennas as far away as possible from living spaces that will be occupied while you are operating
(C)
B-003-021-010 Why should directional high-gain antennas be mounted higher than nearby structures?
A So they will not damage nearby structures with RF energy
B So they will receive more sky waves and fewer ground waves
C So they will not direct RF energy toward people in nearby structures
D So they will be dried by the wind after a heavy rain storm
Station Security
(A)
B-003-018-001 How could you best keep unauthorized persons from using your amateur station at home?
A Use a key-operated on/off switch in the main power line
B Use a carrier-operated relay in the main power line
C Put a "Danger - High Voltage" sign in the station
D Put fuses in the main power line
(A)
B-003-018-002 How could you best keep unauthorized persons from using a mobile amateur station in your car?
A Disconnect the microphone when you are not using it
B Tune the radio to an unused frequency when you are done using it
C Turn the radio off when you are not using it
D Put a "Do not touch" sign on the radio
(D)
B-003-018-003 Why would you use a key-operated on/off switch in the main power line of your station?
A For safety, in case the main fuses fail
B To keep the power company from turning off your electricity during an emergency
C For safety, to turn off the station in the event of an emergency
D To keep unauthorized persons from using your station