005 - Basic Electronics and Theory Flashcards
(142 cards)
1
Q
B-005-001-001
If a dial marked in megahertz shows a reading of 3.525 MHz, what would it show if it were marked in kilohertz?
(a) 3525 kHz
(b) 35.25 kHz
(c) 3 525 000 kHz
(d) 0.003525 kHz
A
B-005-001-001
If a dial marked in megahertz shows a reading of 3.525 MHz, what would it show if it were marked in kilohertz?
(a) 3525 kHz
2
Q
B-005-001-002
If an ammeter marked in amperes is used to measure a 3000 milliampere current, what reading would it show?
(a) 0.003 ampere
(b) 3 amperes
(c) 0.3 ampere
(d) 3 000 000 amperes
A
B-005-001-002
If an ammeter marked in amperes is used to measure a 3000 milliampere current, what reading would it show?
(b) 3 amperes
3
Q
B-005-001-003
If a voltmeter marked in volts is used to measure a 3500 millivolt potential, what reading would it show?
(a) 3.5 volts
(b) 0.35 volt
(c) 35 volts
(d) 350 volts
A
B-005-001-003
If a voltmeter marked in volts is used to measure a 3500 millivolt potential, what reading would it show?
(a) 3.5 volts
4
Q
B-005-001-004
How many microfarads is 1 000 000 picofarads?
(a) 1 microfarad
(b) 1 000 000 000 microfarads
(c) 1000 microfarads
(d) 0.001 microfarad
A
B-005-001-004
How many microfarads is 1 000 000 picofarads?
(a) 1 microfarad
5
Q
B-005-001-005
If you have a hand-held transceiver which puts out 500 milliwatts, how many watts would this be?
(a) 5
(b) 50
(c) 0.02
(d) 0.5
A
B-005-001-005
If you have a hand-held transceiver which puts out 500 milliwatts, how many watts would this be?
(d) 0.5
6
Q
B-005-001-006
A kilohm is:
(a) 0.1 ohm
(b) 0.001 ohm
(c) 1000 ohms
(d) 10 ohms
A
B-005-001-006
A kilohm is:
(c) 1000 ohms
7
Q
B-005-001-007
6.6 kilovolts is equal to:
(a) 660 volts
(b) 6600 volts
(c) 66 volts
(d) 66 000 volts
A
B-005-001-007
6.6 kilovolts is equal to:
(b) 6600 volts
8
Q
B-005-001-008
A current of one quarter ampere may be written as:
(a) 0.5 amperes
(b) 0.25 milliampere
(c) 250 milliamperes
(d) 250 microamperes
A
B-005-001-008
A current of one quarter ampere may be written as:
(c) 250 milliamperes
9
Q
B-005-001-009
How many millivolts are equivalent to two volts?
(a) 2 000
(b) 0.000002
(c) 2 000 000
(d) 0.002
A
B-005-001-009
How many millivolts are equivalent to two volts?
(a) 2 000
10
Q
B-005-001-010
One megahertz is equal to:
(a) 100 kHz
(b) 0.001 Hz
(c) 10 Hz
(d) 1 000 kHz
A
B-005-001-010
One megahertz is equal to:
(d) 1 000 kHz
11
Q
B-005-001-011
An inductance of 10 000 microhenrys may be stated correctly as:
(a) 100 millihenrys
(b) 10 henrys
(c) 10 millihenrys
(d) 1 000 henrys
A
B-005-001-011
An inductance of 10 000 microhenrys may be stated correctly as:
(c) 10 millihenrys
12
Q
B-005-002-001
Name three good electrical conductors.
(a) Gold, silver, wood
(b) Copper, aluminum, paper
(c) Gold, silver, aluminum
(d) Copper, gold, mica
A
B-005-002-001
Name three good electrical conductors.
(c) Gold, silver, aluminum
13
Q
B-005-002-002
Name four good electrical insulators.
(a) Plastic, rubber, wood, carbon
(b) Paper, glass, air, aluminum
(c) Glass, air, plastic, porcelain
(d) Glass, wood, copper, porcelain
A
B-005-002-002
Name four good electrical insulators.
(c) Glass, air, plastic, porcelain
14
Q
B-005-002-003
Why do resistors sometimes get hot when in use?
(a) Their reactance makes them heat up
(b) Hotter circuit components nearby heat them up
(c) Some electrical energy passing through them is lost as heat
(d) They absorb magnetic energy which makes them hot
A
B-005-002-003
Why do resistors sometimes get hot when in use?
(c) Some electrical energy passing through them is lost as heat
15
Q
B-005-002-004
What is the best conductor among the following materials?
(a) carbon
(b) copper
(c) silicon
(d) aluminium
A
B-005-002-004
What is the best conductor among the following materials?
(b) copper
16
Q
B-005-002-005
Which type of material listed will most readily allow an electric current to flow?
(a) an insulator
(b) a conductor
(c) a semiconductor
(d) a dielectric
A
B-005-002-005
Which type of material listed will most readily allow an electric current to flow?
(b) a conductor
17
Q
B-005-002-006
A length of metal is connected in a circuit and is found to conduct electricity very well. It would be best described as having a:
(a) high resistance
(b) low resistance
(c) high wattage
(d) low wattage
A
B-005-002-006
A length of metal is connected in a circuit and is found to conduct electricity very well. It would be best described as having a:
(b) low resistance
18
Q
B-005-002-007
The letter “R” is the symbol for:
(a) impedance
(b) resistance
(c) reluctance
(d) reactance
A
B-005-002-007
The letter “R” is the symbol for:
(b) resistance
19
Q
B-005-002-008
The reciprocal of resistance is:
(a) reactance
(b) reluctance
(c) conductance
(d) permeability
A
B-005-002-008
The reciprocal of resistance is:
(c) conductance
20
Q
B-005-002-009
Voltage drop means:
(a) any point in a radio circuit which has zero voltage
(b) the voltage developed across the terminals of a component
(c) the difference in voltage at output terminals of a transformer
(d) the voltage which is dissipated before useful work is accomplished
A
B-005-002-009
Voltage drop means:
(b) the voltage developed across the terminals of a component
21
Q
B-005-002-010
The resistance of a conductor changes with:
(a) temperature
(b) voltage
(c) current
(d) humidity
A
B-005-002-010
The resistance of a conductor changes with:
(a) temperature
22
Q
B-005-002-011
The most common material used to make a resistor is:
(a) gold
(b) carbon
(c) mica
(d) lead
A
B-005-002-011
The most common material used to make a resistor is:
(b) carbon
23
Q
B-005-003-001
What is the word used to describe the rate at which electrical energy is used?
(a) Power
(b) Current
(c) Voltage
(d) Resistance
A
B-005-003-001
What is the word used to describe the rate at which electrical energy is used?
(a) Power
24
Q
B-005-003-002
If you have light bulbs marked 40 watts, 60 watts and 100 watts, which one will use electrical energy the fastest?
(a) They will all be the same
(b) The 40 watt bulb
(c) The 100 watt bulb
(d) The 60 watt bulb
A
B-005-003-002
If you have light bulbs marked 40 watts, 60 watts and 100 watts, which one will use electrical energy the fastest?
(c) The 100 watt bulb
25
B-005-003-003
What is the basic unit of electrical power?
(a) The watt
(b) The ampere
(c) The volt
(d) The ohm
B-005-003-003
What is the basic unit of electrical power?
(a) The watt
26
B-005-003-004
Which electrical circuit will have no current?
(a) A short circuit
(b) A complete circuit
(c) A closed circuit
(d) An open circuit
B-005-003-004
Which electrical circuit will have no current?
(d) An open circuit
27
B-005-003-005
Which electrical circuit draws too much current?
(a) A dead circuit
(b) A closed circuit
(c) A short circuit
(d) An open circuit
B-005-003-005
Which electrical circuit draws too much current?
(c) A short circuit
28
B-005-003-006
Power is expressed in:
(a) volts
(b) amperes
(c) ohms
(d) watts
B-005-003-006
Power is expressed in:
(d) watts
29
B-005-003-007
Which of the following two quantities should be multiplied together to find power?
(a) Inductance and capacitance
(b) Voltage and current
(c) Voltage and inductance
(d) Resistance and capacitance
B-005-003-007
Which of the following two quantities should be multiplied together to find power?
(b) Voltage and current
30
B-005-003-008
Which two electrical units multiplied together give the unit "watts"?
(a) Volts and amperes
(b) Volts and farads
(c) Farads and henrys
(d) Amperes and henrys
B-005-003-008
Which two electrical units multiplied together give the unit "watts"?
(a) Volts and amperes
31
B-005-003-009
A resistor in a circuit becomes very hot and starts to burn. This is because the resistor is dissipating too much:
(a) power
(b) voltage
(c) resistance
(d) current
B-005-003-009
A resistor in a circuit becomes very hot and starts to burn. This is because the resistor is dissipating too much:
(a) power
32
B-005-003-010
High power resistors are usually large with heavy leads. The size aids the operation of the resistor by:
(a) allowing higher voltage to be handled
(b) increasing the effective resistance of the resistor
(c) making it shock proof
(d) allowing heat to dissipate more readily
B-005-003-010
High power resistors are usually large with heavy leads. The size aids the operation of the resistor by:
(d) allowing heat to dissipate more readily
33
B-005-003-011
The resistor that could dissipate the most heat would be marked:
(a) 100 ohms
(b) 2 ohms
(c) 0.5 watt
(d) 20 watts
B-005-003-011
The resistor that could dissipate the most heat would be marked:
(d) 20 watts
34
B-005-004-001
If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor?
(a) 48 volts
(b) 52 volts
(c) 25 volts
(d) 100 volts
B-005-004-001
If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor?
(d) 100 volts
35
B-005-004-002
How is the current in a DC circuit calculated when the voltage and resistance are known?
(a) Current equals voltage divided by resistance
(b) Current equals resistance multiplied by voltage
(c) Current equals resistance divided by voltage
(d) Current equals power divided by voltage
B-005-004-002
How is the current in a DC circuit calculated when the voltage and resistance are known?
(a) Current equals voltage divided by resistance
36
B-005-004-003
How is the resistance in a DC circuit calculated when the voltage and current are known?
(a) Resistance equals voltage divided by current
(b) Resistance equals current multiplied by voltage
(c) Resistance equals power divided by voltage
(d) Resistance equals current divided by voltage
B-005-004-003
How is the resistance in a DC circuit calculated when the voltage and current are known?
(a) Resistance equals voltage divided by current
37
B-005-004-004
How is the voltage in a DC circuit calculated when the current and resistance are known?
(a) Voltage equals current divided by resistance
(b) Voltage equals resistance divided by current
(c) Voltage equals current multiplied by resistance
(d) Voltage equals power divided by current
B-005-004-004
How is the voltage in a DC circuit calculated when the current and resistance are known?
(c) Voltage equals current multiplied by resistance
38
B-005-004-005
If a 12-volt battery supplies 0.25 ampere to a circuit, what is the circuit's resistance?
(a) 3 ohms
(b) 48 ohms
(c) 12 ohms
(d) 0.25 ohm
B-005-004-005
If a 12-volt battery supplies 0.25 ampere to a circuit, what is the circuit's resistance?
(b) 48 ohms
39
B-005-004-006
Calculate the value of resistance necessary to drop 100 volts with current flow of 0.8 milliamperes:
(a) 125 ohms
(b) 125 kilohms
(c) 1250 ohms
(d) 1.25 kilohms
B-005-004-006
Calculate the value of resistance necessary to drop 100 volts with current flow of 0.8 milliamperes:
(b) 125 kilohms
40
B-005-004-007
The voltage required to force a current of 4.4 amperes through a resistance of 50 ohms is:
(a) 2220 volts
(b) 22.0 volts
(c) 0.220 volt
(d) 220 volts
B-005-004-007
The voltage required to force a current of 4.4 amperes through a resistance of 50 ohms is:
(d) 220 volts
41
B-005-004-008
A lamp has a resistance of 30 ohms and a 6 volt battery is connected. The current flow will be:
(a) 0.2 ampere
(b) 2 amperes
(c) 0.5 ampere
(d) 0.005 ampere
B-005-004-008
A lamp has a resistance of 30 ohms and a 6 volt battery is connected. The current flow will be:
(a) 0.2 ampere
42
B-005-004-009
What voltage would be needed to supply a current of 200 milliamperes, to operate an electric lamp which has a resistance of 25 ohms?
(a) 8 volts
(b) 175 volts
(c) 5 volts
(d) 225 volts
B-005-004-009
What voltage would be needed to supply a current of 200 milliamperes, to operate an electric lamp which has a resistance of 25 ohms?
(c) 5 volts
43
B-005-004-010
The resistance of a circuit can be found by using one of the following:
(a) R = I/E
(b) R = E/I
(c) R = E/R
(d) R = E x I
B-005-004-010
The resistance of a circuit can be found by using one of the following:
(b) R = E/I
44
B-005-004-011
If a 3 volt battery supplies 300 milliamperes to a circuit, the circuit resistance is:
(a) 10 ohms
(b) 9 ohms
(c) 5 ohms
(d) 3 ohms
B-005-004-011
If a 3 volt battery supplies 300 milliamperes to a circuit, the circuit resistance is:
(a) 10 ohms
45
B-005-005-001
In a parallel circuit with a voltage source and several branch resistors, how is the total current related to the current in the branch resistors?
(a) It equals the average of the branch current through each resistor
(b) It equals the sum of the branch current through each resistor
(c) It decreases as more parallel resistors are added to the circuit
(d) It is the sum of each resistor's voltage drop multiplied by the total number of resistors
B-005-005-001
In a parallel circuit with a voltage source and several branch resistors, how is the total current related to the current in the branch resistors?
(b) It equals the sum of the branch current through each resistor
46
B-005-005-002
Three resistors, respectively rated at 10, 15 and 20 ohms are connected in parallel across a 6-volt battery. Which statement is true?
(a) The current flowing through the 10 ohm resistance is less than that flowing through the 20 ohm resistance
(b) The voltage drop across each resistance added together equals 6 volts
(c) The current through the 10 ohms, 15 ohms and 20 ohms separate resistances, when added together, equals the total current drawn from the battery
(d) The voltage drop across the 20 ohm resistance is greater than the voltage across the 10 ohm resistance
B-005-005-002
Three resistors, respectively rated at 10, 15 and 20 ohms are connected in parallel across a 6-volt battery. Which statement is true?
(c) The current through the 10 ohms, 15 ohms and 20 ohms separate resistances, when added together, equals the total current drawn from the battery
47
B-005-005-003
Total resistance in a parallel circuit:
(a) depends upon the voltage drop across each branch
(b) could be equal to the resistance of one branch
(c) depends upon the applied voltage
(d) is always less than the smallest resistance
B-005-005-003
Total resistance in a parallel circuit:
(d) is always less than the smallest resistance
48
B-005-005-004
Two resistors are connected in parallel and are connected across a 40 volt battery. If each resistor is 1000 ohms, the total current is:
(a) 40 milliamperes
(b) 80 milliamperes
(c) 80 amperes
(d) 40 amperes
B-005-005-004
Two resistors are connected in parallel and are connected across a 40 volt battery. If each resistor is 1000 ohms, the total current is:
(b) 80 milliamperes
49
B-005-005-005
The total resistance of resistors connected in series is:
(a) less than the resistance of any one resistor
(b) equal to the highest resistance present
(c) equal to the lowest resistance present
(d) greater than the resistance of any one resistor
B-005-005-005
The total resistance of resistors connected in series is:
(d) greater than the resistance of any one resistor
50
B-005-005-006
Five 10 ohm resistors connected in series equals:
(a) 5 ohms
(b) 10 ohms
(c) 50 ohms
(d) 1 ohm
B-005-005-006
Five 10 ohm resistors connected in series equals:
(c) 50 ohms
51
B-005-005-007
Which series combination of resistors would replace a single 120 ohm resistor?
(a) Six 22 ohm
(b) Two 62 ohm
(c) Five 100 ohm
(d) Five 24 ohm
B-005-005-007
Which series combination of resistors would replace a single 120 ohm resistor?
(d) Five 24 ohm
52
B-005-005-008
If ten resistors of equal value were wired in parallel, the total resistance would be:
(a) R / 10
(b) 10 / R
(c) 10 x R
(d) 10 + R
B-005-005-008
If ten resistors of equal value were wired in parallel, the total resistance would be:
(a) R / 10
53
B-005-005-009
The total resistance of four 68 ohm resistors wired in parallel is:
(a) 12 ohms
(b) 34 ohms
(c) 17 ohms
(d) 272 ohms
B-005-005-009
The total resistance of four 68 ohm resistors wired in parallel is:
(c) 17 ohms
54
B-005-005-010
Two resistors are in parallel. Resistor A carries twice the current of resistor B, which means that:
(a) A has half the resistance of B
(b) the voltage across B is twice that across A
(c) the voltage across A is twice that across B
(d) B has half the resistance of A
B-005-005-010
Two resistors are in parallel. Resistor A carries twice the current of resistor B, which means that:
(a) A has half the resistance of B
55
B-005-005-011
The total current in a parallel circuit is equal to the:
(a) sum of the currents through all the parallel branches
(b) source voltage divided by the value of one of the resistive elements
(c) source voltage divided by the sum of the resistive elements
(d) current in any one of the parallel branches
B-005-005-011
The total current in a parallel circuit is equal to the:
(a) sum of the currents through all the parallel branches
56
B-005-006-001
Why would a large size resistor be used instead of a smaller one of the same resistance?
(a) For better response time
(b) For greater power dissipation
(c) For a higher current gain
(d) For less impedance in the circuit
B-005-006-001
Why would a large size resistor be used instead of a smaller one of the same resistance?
(b) For greater power dissipation
57
B-005-006-002
How many watts of electrical power are used by a 12 volt DC light bulb that draws 0.2 ampere?
(a) 60 watts
(b) 2.4 watts
(c) 24 watts
(d) 6 watts
B-005-006-002
How many watts of electrical power are used by a 12 volt DC light bulb that draws 0.2 ampere?
(b) 2.4 watts
58
B-005-006-003
The DC input power of a transmitter operating at 12 volts and drawing 500 milliamperes would be:
(a) 20 watts
(b) 500 watts
(c) 12 watts
(d) 6 watts
B-005-006-003
The DC input power of a transmitter operating at 12 volts and drawing 500 milliamperes would be:
(d) 6 watts
59
B-005-006-004
When two 500 ohm 1 watt resistors are connected in series, the maximum total power that can be dissipated by the resistors is:
(a) 2 watts
(b) 1 watt
(c) 1/2 watt
(d) 4 watts
B-005-006-004
When two 500 ohm 1 watt resistors are connected in series, the maximum total power that can be dissipated by the resistors is:
(a) 2 watts
60
B-005-006-005
When two 500 ohm 1 watt resistors are connected in parallel, they can dissipate a maximum total power of:
(a) 1/2 watt
(b) 1 watt
(c) 2 watts
(d) 4 watts
B-005-006-005
When two 500 ohm 1 watt resistors are connected in parallel, they can dissipate a maximum total power of:
(c) 2 watts
61
B-005-006-006
If the voltage applied to two resistors in series is doubled, how much will the total power change?
(a) Decrease to half
(b) Increase four times
(c) Double
(d) No change
B-005-006-006
If the voltage applied to two resistors in series is doubled, how much will the total power change?
(b) Increase four times
62
B-005-006-007
Which combination of resistors could make up a 50 ohms dummy load capable of safely dissipating 5 watts?
(a) Two 5-watt 100 ohms resistors in series
(b) Two 2-watt 25 ohms resistors in series
(c) Four 2-watt 200 ohms resistors in parallel
(d) Ten quarter-watt 500 ohms resistors in parallel
B-005-006-007
Which combination of resistors could make up a 50 ohms dummy load capable of safely dissipating 5 watts?
(c) Four 2-watt 200 ohms resistors in parallel
63
B-005-006-008
A 12 volt light bulb is rated at a power of 30 watts. The current drawn would be:
(a) 18 amperes
(b) 30/12 amperes
(c) 360 amperes
(d) 12/30 amperes
B-005-006-008
A 12 volt light bulb is rated at a power of 30 watts. The current drawn would be:
(b) 30/12 amperes
64
B-005-006-009
If two 10 ohm resistors are connected in series with a 10 volt battery, the power consumption would be:
(a) 10 watts
(b) 5 watts
(c) 20 watts
(d) 100 watts
B-005-006-009
If two 10 ohm resistors are connected in series with a 10 volt battery, the power consumption would be:
(b) 5 watts
65
B-005-006-010
One advantage of replacing a 50 ohm resistor with a parallel combination of two similarly rated 100 ohm resistors is that the parallel combination will have:
(a) the same resistance but lesser power rating
(b) greater resistance and similar power rating
(c) the same resistance but greater power rating
(d) lesser resistance and similar power rating
B-005-006-010
One advantage of replacing a 50 ohm resistor with a parallel combination of two similarly rated 100 ohm resistors is that the parallel combination will have:
(c) the same resistance but greater power rating
66
B-005-006-011
Resistor wattage ratings are:
(a) calculated according to physical size and tolerance rating
(b) expressed in joules
(c) variable in steps of one hundred
(d) determined by heat dissipation qualities
B-005-006-011
Resistor wattage ratings are:
(d) determined by heat dissipation qualities
67
B-005-007-001
What term means the number of times per second that an alternating current flows back and forth?
(a) Speed
(b) Pulse rate
(c) Inductance
(d) Frequency
B-005-007-001
What term means the number of times per second that an alternating current flows back and forth?
(d) Frequency
68
B-005-007-002
Approximately what frequency range can most humans hear?
(a) 20 - 20 000 Hz
(b) 20 000 - 30 000 Hz
(c) 200 - 200 000 Hz
(d) 0 - 20 Hz
B-005-007-002
Approximately what frequency range can most humans hear?
(a) 20 - 20 000 Hz
69
B-005-007-003
Why do we call signals in the range 20 Hz to 20 000 Hz audio frequencies?
(a) Because the human ear cannot sense anything in this range
(b) Because this range is too low for radio energy
(c) Because the human ear can sense radio waves in this range
(d) Because the human ear can sense sounds in this range
B-005-007-003
Why do we call signals in the range 20 Hz to 20 000 Hz audio frequencies?
(d) Because the human ear can sense sounds in this range
70
B-005-007-004
Electrical energy at a frequency of 7125 kHz is in what frequency range?
(a) Audio
(b) Hyper
(c) Super-high
(d) Radio
B-005-007-004
Electrical energy at a frequency of 7125 kHz is in what frequency range?
(d) Radio
71
B-005-007-005
What is the name for the distance an AC signal travels during one complete cycle?
(a) Wave speed
(b) Waveform
(c) Wavelength
(d) Wave spread
B-005-007-005
What is the name for the distance an AC signal travels during one complete cycle?
(c) Wavelength
72
B-005-007-006
What happens to a signal's wavelength as its frequency increases?
(a) It gets longer
(b) It stays the same
(c) It disappears
(d) It gets shorter
B-005-007-006
What happens to a signal's wavelength as its frequency increases?
(d) It gets shorter
73
B-005-007-007
What happens to a signal's frequency as its wavelength gets longer?
(a) It disappears
(b) It goes down
(c) It stays the same
(d) It goes up
B-005-007-007
What happens to a signal's frequency as its wavelength gets longer?
(b) It goes down
74
B-005-007-008
What does 60 hertz (Hz) mean?
(a) 6000 metres per second
(b) 60 cycles per second
(c) 60 metres per second
(d) 6000 cycles per second
B-005-007-008
What does 60 hertz (Hz) mean?
(b) 60 cycles per second
75
B-005-007-009
If the frequency of the waveform is 100 Hz, the time for one cycle is:
(a) 10 seconds
(b) 0.0001 second
(c) 0.01 second
(d) 1 second
B-005-007-009
If the frequency of the waveform is 100 Hz, the time for one cycle is:
(c) 0.01 second
76
B-005-007-010
Current in an AC circuit goes through a complete cycle in 0.1 second. This means the AC has a frequency of:
(a) 1 Hz
(b) 100 Hz
(c) 1000 Hz
(d) 10 Hz
B-005-007-010
Current in an AC circuit goes through a complete cycle in 0.1 second. This means the AC has a frequency of:
(d) 10 Hz
77
B-005-007-011
A signal is composed of a fundamental frequency of 2 kHz and another of 4 kHz. This 4 kHz signal is referred to as:
(a) a fundamental of the 2 kHz signal
(b) the DC component of the main signal
(c) a dielectric signal of the main signal
(d) a harmonic of the 2 kHz signal
B-005-007-011
A signal is composed of a fundamental frequency of 2 kHz and another of 4 kHz. This 4 kHz signal is referred to as:
(d) a harmonic of the 2 kHz signal
78
B-005-008-001
A two-times increase in power results in a change of how many dB?
(a) 6 dB higher
(b) 3 dB higher
(c) 12 dB higher
(d) 1 dB higher
B-005-008-001
A two-times increase in power results in a change of how many dB?
(b) 3 dB higher
79
B-005-008-002
How can you decrease your transmitter's power by 3 dB?
(a) Divide the original power by 2
(b) Divide the original power by 1.5
(c) Divide the original power by 3
(d) Divide the original power by 4
B-005-008-002
How can you decrease your transmitter's power by 3 dB?
(a) Divide the original power by 2
80
B-005-008-003
How can you increase your transmitter's power by 6 dB?
(a) Multiply the original power by 4
(b) Multiply the original power by 3
(c) Multiply the original power by 2
(d) Multiply the original power by 1.5
B-005-008-003
How can you increase your transmitter's power by 6 dB?
(a) Multiply the original power by 4
81
B-005-008-004
If a signal-strength report is "10 dB over S9", what should the report be if the transmitter power is reduced from 1500 watts to 150 watts?
(a) S9 plus 3 dB
(b) S9
(c) S9 minus 10 dB
(d) S9 plus 5 dB
B-005-008-004
If a signal-strength report is "10 dB over S9", what should the report be if the transmitter power is reduced from 1500 watts to 150 watts?
(b) S9
82
B-005-008-005
If a signal-strength report is "20 dB over S9", what should the report be if the transmitter power is reduced from 1500 watts to 150 watts?
(a) S9 plus 5 dB
(b) S9 plus 3 dB
(c) S9 plus 10 dB
(d) S9
B-005-008-005
If a signal-strength report is "20 dB over S9", what should the report be if the transmitter power is reduced from 1500 watts to 150 watts?
(c) S9 plus 10 dB
83
B-005-008-006
The unit "decibel" is used to indicate:
(a) an oscilloscope wave form
(b) a mathematical ratio
(c) certain radio waves
(d) a single side band signal
B-005-008-006
The unit "decibel" is used to indicate:
(b) a mathematical ratio
84
B-005-008-007
The power output from a transmitter increases from 1 watt to 2 watts. This is a dB increase of:
(a) 30
(b) 3
(c) 6
(d) 1
B-005-008-007
The power output from a transmitter increases from 1 watt to 2 watts. This is a dB increase of:
(b) 3
85
B-005-008-008
The power of a transmitter is increased from 5 watts to 50 watts by a linear amplifier. The power gain, expressed in dB, is:
(a) 30 dB
(b) 40 dB
(c) 20 dB
(d) 10 dB
B-005-008-008
The power of a transmitter is increased from 5 watts to 50 watts by a linear amplifier. The power gain, expressed in dB, is:
(d) 10 dB
86
B-005-008-009
You add a 9 dB gain amplifier to your 2 watt handheld. What is the power output of the combination?
(a) 16 watts
(b) 11 watts
(c) 20 watts
(d) 18 watts
B-005-008-009
You add a 9 dB gain amplifier to your 2 watt handheld. What is the power output of the combination?
(a) 16 watts
87
B-005-008-010
The power of a transmitter is increased from 2 watts to 8 watts. This is a power gain of __________ dB.
(a) 6 dB
(b) 3 dB
(c) 8 dB
(d) 9 dB
B-005-008-010
The power of a transmitter is increased from 2 watts to 8 watts. This is a power gain of __________ dB.
(a) 6 dB
88
B-005-008-011
A local amateur reports your 100W 2M simplex VHF transmission as 30 dB over S9. To reduce your signal to S9, you would reduce your power to ______ watts.
(a) 100 mW
(b) 1 W
(c) 10 W
(d) 33.3 W
B-005-008-011
A local amateur reports your 100W 2M simplex VHF transmission as 30 dB over S9. To reduce your signal to S9, you would reduce your power to ______ watts.
(a) 100 mW
89
B-005-009-001
If two equal-value inductors are connected in series, what is their total inductance?
(a) Half the value of one inductor
(b) Twice the value of one inductor
(c) The same as the value of either inductor
(d) The value of one inductor times the value of the other
B-005-009-001
If two equal-value inductors are connected in series, what is their total inductance?
(b) Twice the value of one inductor
90
B-005-009-002
If two equal-value inductors are connected in parallel, what is their total inductance?
(a) Half the value of one inductor
(b) Twice the value of one inductor
(c) The same as the value of either inductor
(d) The value of one inductor times the value of the other
B-005-009-002
If two equal-value inductors are connected in parallel, what is their total inductance?
(a) Half the value of one inductor
91
B-005-009-003
If two equal-value capacitors are connected in series, what is their total capacitance?
(a) Twice the value of one capacitor
(b) The same as the value of either capacitor
(c) Half the value of either capacitor
(d) The value of one capacitor times the value of the other
B-005-009-003
If two equal-value capacitors are connected in series, what is their total capacitance?
(c) Half the value of either capacitor
92
B-005-009-004
If two equal-value capacitors are connected in parallel, what is their total capacitance?
(a) The same as the value of either capacitor
(b) Twice the value of one capacitor
(c) The value of one capacitor times the value of the other
(d) Half the value of one capacitor
B-005-009-004
If two equal-value capacitors are connected in parallel, what is their total capacitance?
(b) Twice the value of one capacitor
93
B-005-009-005
What determines the inductance of a coil?
(a) The core material, the number of turns used to wind the coil and the frequency of the current through the coil
(b) The core material, the coil diameter, the length of the coil and the number of turns of wire used to wind the coil
(c) The coil diameter, the number of turns of wire used to wind the coil and the type of metal used for the wire
(d) The core material, the coil diameter, the length of the coil and whether the coil is mounted horizontally or vertically
B-005-009-005
What determines the inductance of a coil?
(b) The core material, the coil diameter, the length of the coil and the number of turns of wire used to wind the coil
94
B-005-009-006
What determines the capacitance of a capacitor?
(a) The material between the plates, the surface area of the plates, the number of plates and the spacing between the plates
(b) The material between the plates, the number of plates and the size of the wires connected to the plates
(c) The number of plates, the spacing between the plates and whether the dielectric material is N type or P type
(d) The material between the plates, the area of one plate, the number of plates and the material used for the protective coating
B-005-009-006
What determines the capacitance of a capacitor?
(a) The material between the plates, the surface area of the plates, the number of plates and the spacing between the plates
95
B-005-009-007
If two equal-value capacitors are connected in parallel, what is their capacitance?
(a) The same value of either capacitor
(b) Twice the value of either capacitor
(c) The value of one capacitor times the value of the other
(d) Half the value of either capacitor
B-005-009-007
If two equal-value capacitors are connected in parallel, what is their capacitance?
(b) Twice the value of either capacitor
96
B-005-009-008
To replace a faulty 10 millihenry choke, you could use two:
(a) 20 millihenry chokes in series
(b) 5 millihenry chokes in series
(c) 30 millihenry chokes in parallel
(d) 5 millihenry chokes in parallel
B-005-009-008
To replace a faulty 10 millihenry choke, you could use two:
(b) 5 millihenry chokes in series
97
B-005-009-009
Three 15 microfarad capacitors are wired in series. The total capacitance of this arrangement is:
(a) 5 microfarads
(b) 45 microfarads
(c) 12 microfarads
(d) 18 microfarads
B-005-009-009
Three 15 microfarad capacitors are wired in series. The total capacitance of this arrangement is:
(a) 5 microfarads
98
B-005-009-010
Which series combinations of capacitors would best replace a faulty 10 microfarad capacitor?
(a) Two 20 microfarad capacitors
(b) Two 10 microfarad capacitors
(c) Twenty 2 microfarad capacitors
(d) Ten 2 microfarad capacitors
B-005-009-010
Which series combinations of capacitors would best replace a faulty 10 microfarad capacitor?
(a) Two 20 microfarad capacitors
99
B-005-009-011
The total capacitance of two or more capacitors in series is:
(a) found by adding each of the capacitors together and dividing by the total number of capacitors
(b) found by adding each of the capacitors together
(c) always less than the smallest capacitor
(d) always greater than the largest capacitor
B-005-009-011
The total capacitance of two or more capacitors in series is:
(c) always less than the smallest capacitor
100
B-005-010-001
How does a coil react to AC?
(a) As the amplitude of the applied AC increases, the reactance decreases
(b) As the amplitude of the applied AC increases, the reactance increases
(c) As the frequency of the applied AC increases, the reactance increases
(d) As the frequency of the applied AC increases, the reactance decreases
B-005-010-001
How does a coil react to AC?
(c) As the frequency of the applied AC increases, the reactance increases
101
B-005-010-002
How does a capacitor react to AC?
(a) As the frequency of the applied AC increases, the reactance increases
(b) As the frequency of the applied AC increases, the reactance decreases
(c) As the amplitude of the applied AC increases, the reactance increases
(d) As the amplitude of the applied AC increases, the reactance decreases
B-005-010-002
How does a capacitor react to AC?
(b) As the frequency of the applied AC increases, the reactance decreases
102
B-005-010-003
The reactance of capacitors increases as:
(a) applied voltage increases
(b) applied voltage decreases
(c) frequency decreases
(d) frequency increases
B-005-010-003
The reactance of capacitors increases as:
(c) frequency decreases
103
B-005-010-004
In inductances, AC may be opposed by both resistance of winding wire and reactance due to inductive effect. The term which includes resistance and reactance is:
(a) resonance
(b) inductance
(c) impedance
(d) capacitance
B-005-010-004
In inductances, AC may be opposed by both resistance of winding wire and reactance due to inductive effect. The term which includes resistance and reactance is:
(c) impedance
104
B-005-010-005
Capacitive reactance:
(a) decreases as frequency increases
(b) applies only to series RLC circuits
(c) increases as frequency increases
(d) increases with the time constant
B-005-010-005
Capacitive reactance:
(a) decreases as frequency increases
105
B-005-010-006
Inductive reactance may be increased by:
(a) a decrease in the applied frequency
(b) a decrease in the supplied current
(c) an increase in the applied frequency
(d) an increase in the applied voltage
B-005-010-006
Inductive reactance may be increased by:
(c) an increase in the applied frequency
106
B-005-010-007
What property allows a coil wound on a ferrite core to mitigate the effects of an offending radio signal?
(a) High reactance at radio frequencies
(b) Low reactance at radio frequencies
(c) Low reactance at audio frequencies
(d) High reactance at audio frequencies
B-005-010-007
What property allows a coil wound on a ferrite core to mitigate the effects of an offending radio signal?
(a) High reactance at radio frequencies
107
B-005-010-008
What property allows an RF bypass capacitor on an audio circuit to divert an offending radio signal?
(a) High reactance at radio frequencies
(b) Low reactance at radio frequencies
(c) Low reactance at audio frequencies
(d) High reactance at audio frequencies
B-005-010-008
What property allows an RF bypass capacitor on an audio circuit to divert an offending radio signal?
(b) Low reactance at radio frequencies
108
B-005-010-009
What property allows an RF bypass capacitor to have little effect on an audio circuit?
(a) Low reactance at high frequencies
(b) High reactance at low frequencies
(c) High reactance at high frequencies
(d) Low reactance at low frequencies
B-005-010-009
What property allows an RF bypass capacitor to have little effect on an audio circuit?
(b) High reactance at low frequencies
109
B-005-010-010
What property allows an RF choke coil to have little effect on signals meant to flow through the coil?
(a) Low reactance at low frequencies
(b) High reactance at low frequencies
(c) Low reactance at high frequencies
(d) High reactance at high frequencies
B-005-010-010
What property allows an RF choke coil to have little effect on signals meant to flow through the coil?
(a) Low reactance at low frequencies
110
B-005-010-011
In general, the reactance of inductors increases with:
(a) decreasing AC frequency
(b) decreasing applied voltage
(c) increasing AC frequency
(d) increasing applied voltage
B-005-010-011
In general, the reactance of inductors increases with:
(c) increasing AC frequency
111
B-005-011-001
If no load is attached to the secondary winding of a transformer, what is current in the primary winding called?
(a) Direct current
(b) Latent current
(c) Stabilizing current
(d) Magnetizing current
B-005-011-001
If no load is attached to the secondary winding of a transformer, what is current in the primary winding called?
(d) Magnetizing current
112
B-005-011-002
A transformer operates a 6.3 volt 2 ampere light bulb from its secondary winding. The input power to the primary winding is approximately:
(a) 13 watts
(b) 6 watts
(c) 8 watts
(d) 3 watts
B-005-011-002
A transformer operates a 6.3 volt 2 ampere light bulb from its secondary winding. The input power to the primary winding is approximately:
(a) 13 watts
113
B-005-011-003
A transformer has a 240 volt primary that draws a current of 250 milliamperes from the mains supply. Assuming no losses and only one secondary, what current would be available from the 12 volt secondary?
(a) 5 amperes
(b) 215 amperes
(c) 25 amperes
(d) 50 amperes
B-005-011-003
A transformer has a 240 volt primary that draws a current of 250 milliamperes from the mains supply. Assuming no losses and only one secondary, what current would be available from the 12 volt secondary?
(a) 5 amperes
114
B-005-011-004
In a mains power transformer, the primary winding has 250 turns, and the secondary has 500. If the input voltage is 120 volts, the likely secondary voltage is:
(a) 480 V
(b) 610 V
(c) 26 V
(d) 240 V
B-005-011-004
In a mains power transformer, the primary winding has 250 turns, and the secondary has 500. If the input voltage is 120 volts, the likely secondary voltage is:
(d) 240 V
115
B-005-011-005
The strength of the magnetic field around a conductor in air is:
(a) inversely proportional to the diameter of the conductor
(b) directly proportional to the diameter of the conductor
(c) directly proportional to the current in the conductor
(d) inversely proportional to the voltage on the conductor
B-005-011-005
The strength of the magnetic field around a conductor in air is:
(c) directly proportional to the current in the conductor
116
B-005-011-006
Maximum induced voltage in a coil occurs when:
(a) the current through the coil is of a DC nature
(b) current is going through its least rate of change
(c) the magnetic field around the coil is not changing
(d) current is going through its greatest rate of change
B-005-011-006
Maximum induced voltage in a coil occurs when:
(d) current is going through its greatest rate of change
117
B-005-011-007
The voltage induced in a conductor moving in a magnetic field is at a maximum when the movement is:
(a) made in a counter clockwise direction
(b) parallel to the lines of force
(c) perpendicular to the lines of force
(d) made in a clockwise direction
B-005-011-007
The voltage induced in a conductor moving in a magnetic field is at a maximum when the movement is:
(c) perpendicular to the lines of force
118
B-005-011-008
A 100% efficient transformer has a turns ratio of 1/5. If the secondary current is 50 milliamperes, the primary current is:
(a) 2 500 mA
(b) 0.01 A
(c) 0.25 mA
(d) 0.25 A
B-005-011-008
A 100% efficient transformer has a turns ratio of 1/5. If the secondary current is 50 milliamperes, the primary current is:
(d) 0.25 A
119
B-005-011-009
A force of repulsion exists between two _________ magnetic poles.
(a) unlike
(b) positive
(c) negative
(d) like
B-005-011-009
A force of repulsion exists between two _________ magnetic poles.
(d) like
120
B-005-011-010
A permanent magnet would most likely be made from:
(a) copper
(b) steel
(c) aluminum
(d) brass
B-005-011-010
A permanent magnet would most likely be made from:
(b) steel
121
B-005-011-011
The fact that energy transfer from primary to secondary windings in a power transformer is not perfect is indicated by:
(a) electrostatic shielding
(b) large secondary currents
(c) high primary voltages
(d) warm iron laminations
B-005-011-011
The fact that energy transfer from primary to secondary windings in a power transformer is not perfect is indicated by:
(d) warm iron laminations
122
B-005-012-001
Resonance is the condition that exists when:
(a) inductive reactance is the only opposition in the circuit
(b) the circuit contains no resistance
(c) resistance is equal to the reactance
(d) inductive reactance and capacitive reactance are equal
B-005-012-001
Resonance is the condition that exists when:
(d) inductive reactance and capacitive reactance are equal
123
B-005-012-002
Parallel tuned circuits offer:
(a) high impedance at resonance
(b) low impedance at resonance
(c) zero impedance at resonance
(d) an impedance equal to resistance of the circuit
B-005-012-002
Parallel tuned circuits offer:
(a) high impedance at resonance
124
B-005-012-003
Resonance is an electrical property used to describe:
(a) an inductor
(b) a set of parallel inductors
(c) the results of tuning a varicap (varactor)
(d) the frequency characteristic of a coil and capacitor circuit
B-005-012-003
Resonance is an electrical property used to describe:
(d) the frequency characteristic of a coil and capacitor circuit
125
B-005-012-004
A tuned circuit is formed from two basic components. These are:
(a) inductors and capacitors
(b) resistors and transistors
(c) directors and reflectors
(d) diodes and transistors
B-005-012-004
A tuned circuit is formed from two basic components. These are:
(a) inductors and capacitors
126
B-005-012-005
When a parallel coil-capacitor combination is supplied with AC of different frequencies, there will be one frequency where the impedance will be highest. This is the:
(a) resonant frequency
(b) impedance frequency
(c) inductive frequency
(d) reactive frequency
B-005-012-005
When a parallel coil-capacitor combination is supplied with AC of different frequencies, there will be one frequency where the impedance will be highest. This is the:
(a) resonant frequency
127
B-005-012-006
In a parallel-resonant circuit at resonance, the circuit has a:
(a) high impedance
(b) low impedance
(c) low mutual inductance
(d) high mutual inductance
B-005-012-006
In a parallel-resonant circuit at resonance, the circuit has a:
(a) high impedance
128
B-005-012-007
In a series resonant circuit at resonance, the circuit has:
(a) low impedance
(b) high impedance
(c) low mutual inductance
(d) high mutual inductance
B-005-012-007
In a series resonant circuit at resonance, the circuit has:
(a) low impedance
129
B-005-012-008
A coil and an air-spaced capacitor are arranged to form a resonant circuit. The resonant frequency will remain the same if we:
(a) increase the area of plates in the capacitor
(b) insert Mylar sheets between the plates of the capacitor
(c) wind more turns on the coil
(d) add a resistor to the circuit
B-005-012-008
A coil and an air-spaced capacitor are arranged to form a resonant circuit. The resonant frequency will remain the same if we:
(d) add a resistor to the circuit
130
B-005-012-009
Resonant circuits in a receiver are used to:
(a) filter direct current
(b) increase power
(c) select signal frequencies
(d) adjust voltage levels
B-005-012-009
Resonant circuits in a receiver are used to:
(c) select signal frequencies
131
B-005-012-010
Resonance is the condition that exists when:
(a) inductive reactance is the only opposition in the circuit
(b) inductive reactance and capacitive reactance are equal and opposite in sign
(c) the circuit contains no resistance
(d) resistance is equal to the reactance
B-005-012-010
Resonance is the condition that exists when:
(b) inductive reactance and capacitive reactance are equal and opposite in sign
132
B-005-012-011
When a series LCR circuit is tuned to the frequency of the source, the:
(a) line current reaches maximum
(b) line current lags the applied voltage
(c) line current leads the applied voltage
(d) impedance is maximum
B-005-012-011
When a series LCR circuit is tuned to the frequency of the source, the:
(a) line current reaches maximum
133
B-005-013-001
How is a voltmeter usually connected to a circuit under test?
(a) In series with the circuit
(b) In quadrature with the circuit
(c) In parallel with the circuit
(d) In phase with the circuit
B-005-013-001
How is a voltmeter usually connected to a circuit under test?
(c) In parallel with the circuit
134
B-005-013-002
How is an ammeter usually connected to a circuit under test?
(a) In series with the circuit
(b) In quadrature with the circuit
(c) In phase with the circuit
(d) In parallel with the circuit
B-005-013-002
How is an ammeter usually connected to a circuit under test?
(a) In series with the circuit
135
B-005-013-003
What does a multimeter measure?
(a) Resistance, capacitance and inductance
(b) Voltage, current and resistance
(c) Resistance and reactance
(d) SWR and power
B-005-013-003
What does a multimeter measure?
(b) Voltage, current and resistance
136
B-005-013-004
The correct instrument to measure plate current or collector current of a transmitter is:
(a) an ammeter
(b) an ohmmeter
(c) a wattmeter
(d) a voltmeter
B-005-013-004
The correct instrument to measure plate current or collector current of a transmitter is:
(a) an ammeter
137
B-005-013-005
Which of the following meters would you use to measure the power supply current drawn by a small hand-held transistorized receiver?
(a) An RF ammeter
(b) An RF power meter
(c) An electrostatic voltmeter
(d) A DC ammeter
B-005-013-005
Which of the following meters would you use to measure the power supply current drawn by a small hand-held transistorized receiver?
(d) A DC ammeter
138
B-005-013-006
When measuring current drawn from a DC power supply, it is true to say that the meter will act in circuit as:
(a) a perfect conductor
(b) an extra current drain
(c) a low value resistance
(d) an insulator
B-005-013-006
When measuring current drawn from a DC power supply, it is true to say that the meter will act in circuit as:
(c) a low value resistance
139
B-005-013-007
When measuring the current drawn by a receiver from a power supply, the current meter should be placed:
(a) in series with one of the receiver power leads
(b) in series with both receiver power leads
(c) in parallel with both receiver power supply leads
(d) in parallel with one of the receiver power leads
B-005-013-007
When measuring the current drawn by a receiver from a power supply, the current meter should be placed:
(a) in series with one of the receiver power leads
140
B-005-013-008
Potential difference is measured by means of:
(a) a wattmeter
(b) a voltmeter
(c) an ohmmeter
(d) an ammeter
B-005-013-008
Potential difference is measured by means of:
(b) a voltmeter
141
B-005-013-009
The instrument used for measuring the flow of electrical current is the:
(a) ammeter
(b) faradmeter
(c) wattmeter
(d) voltmeter
B-005-013-009
The instrument used for measuring the flow of electrical current is the:
(a) ammeter
142
B-005-013-010
In measuring volts and amperes, the connections should be made with:
(a) the voltmeter in series and ammeter in parallel
(b) the voltmeter in parallel and ammeter in series
(c) both voltmeter and ammeter in series
(d) both voltmeter and ammeter in parallel
B-005-013-010
In measuring volts and amperes, the connections should be made with:
(b) the voltmeter in parallel and ammeter in series
