4/18/2012
Amateur Radio Technician Class
El
Element
t2C
Course P
Presentation
t ti
¾ ELEMENT 2 SUB-ELEMENTS
– T1 - FCC Rules, descriptions and definitions for the amateur radio
service, operator and station license responsibilities.
– T2 – Operating Procedures
– T3 – Radio wave characteristics, radio and electromagnetic properties,
propagation modes
– T4 – Amateur radio practices and station set up
¾ T5 – Electrical principles, math for electronics, electronic principles,
Ohm’s Law
– T6 – Electrical components, semiconductors, circuit diagrams,
component functions
– T7 – Station equipment, common transmitter and receiver problems,
antenna
t
measurements
t and
d ttroubleshooting,
bl h ti
b
basic
i repair
i and
d ttesting
ti
– T8 – Modulation modes, amateur satellite operation, operating activities,
non-voice communications
– T9 – Antennas, feedlines
– T0 – AC power circuits
circuits, antenna installation,
installation RF hazards
Technician Licensing Class
Supplement T5
Electrical/Electronic Principles
4 Exam Questions, 4 Groups
2
T5A:
–
T5A1
–
T5A2
Electrical principles; current and voltage, conductors and insulators, alternating
and direct current
T5A:
Electrical current is measured in amperes.
El
Electrical
i l power iis measured
d iin watts.
Electrical principles; current and voltage, conductors and insulators, alternating
–
» The power meter outside is called ‘watt meter’
Voltage is the electrical term for the electromotive force
(EMF) that causes electron flow.
T5A5
– Think of voltage as water pressure in the pipes (not the flow)
Current is the name for the flow of electrons in an electric
circuit
circuit.
–
T5A3
–
T5A4
and direct current
» Think of the flow of water in a pipe (not the force)
Direct current is the name for a current that flows only in one
direction.
direction
–
T5A6
A mobile transceiver usually requires about 12 volts.
–
T5A7
C
Copper
is
i a good
d electrical
l t i l conductor.
d t
–
T5A8
Glass is a g
good electrical insulator.
Copper is
a good
conductor
Glass is a
good
insulator
9 Volt
battery
T5A:
–
AAA
battery
Motor cycle
battery
Hand held
battery
Electrical principles; current and voltage, conductors and insulators, alternating
3
4
T5B:
and direct current
Alternating current is the name for a current that reverses
direction on a regular basis.
basis
T5A9
Math for electronics; decibels, electrical units and the metric system
1,500 milliamperes is 1.5 amperes.
–
T5B1
•
T5B2
•
T5B3
One thousand volts are equal to one kilovolt.
–
T5B4
One one-millionth of a volts is equal to one microvolt.
–
T5B5
0.5 watts is equivalent to 500 milliwatts.
–
T5B6
1500 kHz is another way to specify a radio signal frequency of
1,500,000 hertz.
If an ammeter calibrated in amperes is used to measure a 3000
3000milliampere of current, the reading would it to be 3 amperes.
Power is the term that describes the rate at which electrical
energy is
i used.
d
–
T5A10
–
T5A11
The volt is the basic unit of electromotive force.
5
6
1
4/18/2012
T5B:
T5B:
Math for electronics; decibels, electrical units and the metric system
Metric
Exponent
Tera
T
Giga
Mega
Kilo
1012
109
106
103
Trillion
T
illi
Billion
Million
Thousand
English
Centi
Milli
Micro
Nano
Pico
10-2
10-3
10-6
10-9
12
10-12
Hundredth
Thousandth
Millionth
Billionth
Trillionth
If a frequency readout calibrated in megahertz shows a reading of
3.525
3
525 MHz,
MHz it would show 3525 kHz if it were calibrated in kilohertz.
kilohertz
–
T5B7
–
T5B8
–
T5B9
One microfarads is equal to 1,000,000 picofarads.
The approximate amount of change, measured in decibels (dB), of
a power increase from 5 watts to 10 watts is 3dB
3dB. 3 dB gain
i iis a d
double
bl off power
dB
Scientific Notation
T5C:
1012
109
106
103
102
101
100
1,000,000,000,000
1,000,000,000
1,000,000
1,000
100
10
1
deci
centi
milli
micro
nano
pico
femto
10-1
10-2
10-3
10-6
10
0-99
10-12
10-15
Electronic principles; capacitance, inductance, current flow in circuits,
of RF, power calculations
0.1
0.01
0.001
0.000001
0 00000000
0.000000001
0.000000000001
0.000000000000001
7
7
T5C1
–
T5C2
–
T5C3
–
T5C4
The basic unit of inductance is the henry.
–
T5C5
Hertz is the unit of frequency.
–
The basic unit of capacitance
p
is the farad.
The ability to store energy in a magnetic field is called
inductance
inductance.
2x
4x
8x
10x
100x
1000x
10,000x
Power change
Power change
Power change
Power change
Power change
Power change
Power change
The approximate amount of change, measured in decibels (dB),
of a power decrease from 12 watts to 3 watts is 6dB
6dB.
–
T5B10
–
T5B11
The approximate amount of change, measured in decibels (dB),
8
of a power increase from 20 watts to 200 watts is 10 dB.
T5C:
alternating current, definition
The ability to store energy in an electric field is called
capacitance.
–
Power Change
3 dB
6 dB
9 dB
10 dB
20 dB
30 dB
40 dB
Prefix
Multiplication
p
Factor
Prefix
Multiplication
p
Factor
____________________________________________________
tera
giga
mega
kilo
hecto
deca
unit
Math for electronics; decibels, electrical units and the metric system
Electronic principles; capacitance, inductance, current flow in circuits,
power calculations
definition of RF, p
alternating current,
T5C6 RF is the
abbreviation
bb i ti that
th t
refers to radio
frequency signals
of all types
types.
– Term “RF” refers to
radio frequency
10
9
T5C:
–
Electronic principles; capacitance, inductance, current flow in circuits,
p
calculations
definition of RF,, power
10
T5C:
alternating current,
Radio waves is a usual name for electromagnetic waves that travel
through space.
space
T5C7
– Electromagnetic waves are RADIO WAVES
Electronic principles; capacitance, inductance, current flow in circuits,
of RF, power calculations
alternating current, definition
Power ((P)) equals
q
voltage
g ((E)) multiplied
p
by
y current ((I)) is the
formula used to calculate electrical power in a DC circuit.
T5C8
» P is for p
power,, E is for Voltage,
g , and I is for current
The math is easy
Two known
numbers are
given, solve for
the unknown
11
11
Cover up the unknown and plug
tthe
e numbers
u be s in tthe
e ot
other
e two
P=IxE
I=P/E
E=P/I
Finding Power
Finding Amperes
Finding Voltage
12
12
2
4/18/2012
T5C:
–
Electronic principles; capacitance, inductance, current flow in circuits,
of RF, power calculations
alternating current, definition
138 watts of power is being used in a circuit when the applied
voltage is 13.8 volts DC and the current is 10 amperes.
T5C9
T5C:
–
Electronic principles; capacitance, inductance, current flow in circuits,
of RF, power calculations
alternating current, definition
30 watts of power is being used in a circuit when the applied
voltage is 12 volts DC and the current is 2.5 amperes.
T5C10
– Solving for “P” so cover up the P and plug in the other two numbers
– Solving for “P” so cover up the “P” and plug in the other two numbers
– E is given as 13.8 volts and I is given as 10 amperes
– E is given as 12 volts and I is given as 2.5 amperes
P=IxE
P=IxE
P = 10 x 13.8
P = 2.5 x 12
P = 138 watts
P = 30 watts
13
14
13
T5C:
–
Electronic principles; capacitance, inductance, current flow in circuits,
of RF, power calculations
14
T5D
alternating current, definition
10 amperes are flowing in a circuit when the applied voltage
is 12 volts DC and the load is 120 watts.
T5C11
–
Ohm’s Law
T5D1 The formula Current (I) equals voltage (E) divided by
resistance (R) is used to calculate current in a circuit.
– E is for Voltage, I is for current, and R is for resistance
– Solving for “I” so cover up the “I” and plug in the other two numbers
– P is given as 120 watts and E is given as 12 volts and
The math is easy
Two known
numbers are
given, solve for
the unknown
I=P/E
Cover up the unknown and plug
the numbers in the other two
I = 120 / 12
I = 10 Amperes
15
15
T5D
–
I=E/R
E=IxR
Finding Amperes
Finding Voltage
T5D
Ohm’s Law
The formula Voltage (E) equals current (I) multiplied by
resistance (R) is used to calculate voltage in a circuit.
T5D2
– E is for Voltage, I is for current, and R is for resistance
The math is easy
–
R= E / I
Finding Resistance 16
16
Ohm’s Law
T5D3 The formula Resistance (R) equals voltage (E) divided by
current (I) is used to calculate resistance in a circuit.
– E is for Voltage, I is for current, and R is for resistance
The math is easy
Two known
numbers are
given, solve for
the unknown
Cover up the unknown and plug
the numbers in the other two
E=IxR
I=E/R
Finding Voltage
Finding Amperes
R= E / I
Finding Resistance 17
17
Two known
numbers are
given, solve for
the unknown
Cover up the unknown and plug
the numbers in the other two
R= E / I
I=E/R
E=IxR
Finding Resistance
Finding Amperes
Finding Voltage
18
18
3
4/18/2012
T5D
–
T5D
Ohm’s Law
The resistance of a circuit in which a current of 3 amperes flows
through a resistor connected to 90 volts is 30 ohms.
T5D4
–
Ohm’s Law
The resistance in a circuit for which the applied voltage is 12
volts and the current flow is 1.5 amperes is 8 ohms.
T5D5
• Solving for “R” so cover up the “R” and plug in the other two numbers
• E is given as 12 volts and I is given as 1
1.5
5 amperes
• Solving for “R” so cover up the “R” and plug in the other two numbers
• E is given as 90 volts and I is given as 3 amperes
R=E/I
R=E/I
R = 90 / 3
R = 12 / 1.5
R = 30 ohms
R = 8 ohms
19
20
19
T5D
–
20
T5D
Ohm’s Law
The resistance of a circuit that draws 4 amperes from a 12
12-volt
volt
source is 3 ohms.
T5D6
–
Ohm’s Law
The current flow in a circuit with an applied voltage of 120 volts
and a resistance of 80 ohms is 1.5 amperes.
T5D7
• Solving for “R” so cover up the “R” and plug in the other two numbers
• E is given as 12 volts and I is given as 4 amperes
• Solving for “I” so cover up the “I” and plug in the other two numbers
• E is given as 120 volts and R is given as 80 ohms
R=E/I
I=E/R
R = 12 / 4
I = 120 / 80
R = 3 ohms
I = 1.5 amperes
21
22
21
T5D
–
22
T5D
Ohm’s Law
The current flowing through a 100-ohm resistor connected across
200 volts 2 amperes.
T5D8
• Solving for “I” so cover up the “I” and plug in the other two numbers
• E is given as 200 volts and R is given as 100 ohms
–
Ohm’s Law
T5D9 The current flowing through a 24-ohm resistor connected across
240 volts 10 amperes.
• Solving for “I” so cover up the “I” and plug in the other two numbers
• E is given as 240 volts and R is given as 24 ohms
I=E/R
I=E/R
I = 200 / 100
I = 240 / 24
I = 2 amperes
I = 10 amperes
23
23
24
24
4
4/18/2012
T5D
–
T5D
Ohm’s Law
The voltage across a 2-ohm resistor if a current of 0.5 amperes
flows through it is 1 volt.
T5D10
• Solving for “E” so cover up the “E” and plug in the other two numbers
• I is given as 0
0.5
5 amperes and R is given as 2 ohms
–
Ohm’s Law
T5D11 The voltage across a 10-ohm resistor if a current of 1 amperes
flows through it is 10 volts.
• Solving
S l i for
f “E” so cover up the
th “E” and
d plug
l in
i th
the other
th ttwo numbers
b
• I is given as 1 ampere and R is given as 10 ohms
E=IxR
E=IxR
E = 0.5 x 2
E = 1 x 10
E= 1 volt
E= 10 volts
25
26
25
T5D
–
26
T5D
Ohm’s Law
Ohm’s Law
T5D12 The voltage across a 10-ohm resistor if a current of 2 amperes
flows through it is 20 volts.
• Solving
S l i for
f “E” so cover up the
th “E” and
d plug
l in
i th
the other
th ttwo numbers
b
• I is given as 1 ampere and R is given as 10 ohms
E=IxR
E = 2 x 10
E= 20 volts
27
28
27
Element 2 Technician Class
Q ti Pool
Question
P l
T5
Electrical principles, math for electronics, electronic
principles, Ohm’s Law
[4 Exam Questions – 4 Groups]
28
T5A01
A.
B.
C.
D.
Electrical current is measured in which of
the following units?
Volts
Watts
Ohms
Amperes
p
V lid July
Valid
J l 1,
1 2010
Through
June 30, 2014
30
5
4/18/2012
T5A02
A.
B.
C.
D.
T5A03
Electrical p
power is measured in which of
the following units?
Volts
Watts
Ohms
Amperes
p
A.
B.
C.
D.
What is the name for the flow of electrons in
an electric circuit?
Voltage
Resistance
Capacitance
Current
31
T5A04
A.
B.
C.
D.
What is the name for a current that flows
only in one direction?
32
T5A05
Alternating current
Direct current
Normal current
Smooth current
A.
B.
C.
D.
What is the electrical term for the
electromotive force (EMF) that causes
electron flow?
Voltage
Ampere-hours
p
Capacitance
Inductance
33
T5A06
A.
B.
C.
D.
How much voltage
g does a mobile
transceiver usually require?
34
T5A07
About 12 volts
About 30 volts
About 120 volts
About 240 volts
A.
B.
C.
D.
35
Which of the following is a good electrical
conductor?
Glass
Wood
Copper
Rubber
36
6
4/18/2012
T5A08
A.
B.
C.
D.
Which of the following
g is a g
good electrical
insulator?
T5A09
Copper
Glass
Aluminum
Mercury
y
A.
B.
C.
D.
What is the name for a current that reverses
direction on a regular basis?
Alternating current
Direct current
Circular current
Vertical current
37
T5A10
A.
B.
C.
D.
38
T5A11
Which term describes the rate at which
electrical energy is used?
A.
B.
C.
D.
Resistance
Current
Power
g
Voltage
What is the basic unit of electromotive
force?
The volt
The watt
The ampere
The ohm
39
T5B01
A.
B.
C.
D.
How many
y milliamperes
p
is 1.5 amperes?
p
40
T5B02
15 milliamperes
150 milliamperes
p
1,500 milliamperes
15,000
,
milliamperes
p
A.
B.
C.
D.
41
What is another way to specify a radio
signal frequency of 1,500,000 hertz?
1500 kHz
1500 MHz
15 GHz
15 kHz
42
7
4/18/2012
T5B03
A.
B.
C.
D.
How many volts are equal to one kilovolt?
One one-thousandth of a volt
One hundred volts
One thousand volts
One million volts
T5B04
A.
B.
C.
D.
How many
y volts are equal
q
to one microvolt?
One one-millionth of a volt
One million volts
One thousand kilovolts
One one-thousandth of a volt
43
T5B05
A.
B.
C.
D.
44
T5B06
Which of the following is equivalent to 500
milliwatts?
0.02 watts
0.5 watts
5 watts
50 watts
A.
B.
C.
D.
If an ammeter calibrated in amperes is
used to measure a 3000-milliampere
current, what reading would it show?
0.003 amperes
0.3 amperes
p
3 amperes
,
,
amperes
p
3,000,000
45
T5B07
A.
B.
C.
D.
46
T5B08
If a frequency
q
y readout calibrated in megahertz
g
shows a reading of 3.525 MHz, what would it show
if it were calibrated in kilohertz?
0.003525 kHz
35.25 kHz
3525 kHz
3,525,000
,
,
kHz
A.
B.
C.
D.
47
How many
y microfarads are 1,000,000
,
,
picofarads?
0.001 microfarads
1 microfarad
1000 microfarads
1,000,000,000
,
,
,
microfarads
48
8
4/18/2012
T5B09
A.
B.
C.
D.
What is the approximate
pp
amount of change,
g ,
measured in decibels (dB), of a power increase
from 5 watts to 10 watts?
T5B10
2 dB
3 dB
5 dB
10 dB
A.
B.
C.
D.
What is the approximate amount of change,
change
measured in decibels (dB), of a power decrease
from 12 watts to 3 watts?
1 dB
3 dB
6 dB
9 dB
49
T5B11
A.
B.
C.
D.
50
T5C01
What is the approximate amount of change,
change
measured in decibels (dB), of a power increase
from 20 watts to 200 watts?
10 dB
12 dB
18 dB
28 dB
A.
B.
C.
D.
What is the ability to store energy in an
electric field called?
Inductance
Resistance
Tolerance
p
Capacitance
51
T5C02
A.
B.
C.
D.
52
T5C03
What is the basic unit of capacitance?
p
The farad
The ohm
The volt
The henry
y
A.
B.
C.
D.
53
What is the ability
y to store energy
gy in a
magnetic field called?
Admittance
Capacitance
p
Resistance
Inductance
54
9
4/18/2012
T5C04
A.
B.
C.
D.
What is the basic unit of inductance?
T5C05
The coulomb
The farad
The henry
The ohm
A.
B.
C.
D.
What is the unit of frequency?
Hertz
Henry
y
Farad
Tesla
55
T5C06
A.
B.
C.
D.
What is the abbreviation that refers to radio
frequency signals of all types?
AF
HF
RF
VHF
56
T5C07
A.
B.
C.
D.
What is a usual name for electromagnetic
g
waves that travel through space?
Gravity waves
Sound waves
Radio waves
Pressure waves
57
T5C08
What is the formula used to calculate
electrical power in a DC circuit?
58
T5C09
A. Power (P) equals voltage (E) multiplied
by current (I)
B. Power (P)
( ) equals voltage ((E)) divided
i i
by
current (I)
C Power (P) equals voltage (E) minus
C.
current (I)
q
voltage
g ((E)) p
plus
D. Power ((P)) equals
current (I)
A.
B.
C.
D.
59
How much power is being used in a circuit
when the applied voltage is 13.8 volts DC
and the current is 10 amperes?
138 watts
0.7 watts
23.8 watts
3.8 watts
60
10
4/18/2012
T5C10
How much power is being used in a circuit
when the applied voltage is 12 volts DC
and
the current is 2.5 amperes?
A.
B.
C.
D.
4.8 watts
30 watts
14.5 watts
0.208 watts
T5C11
How many amperes are flowing in a circuit
when the applied voltage is 12 volts DC
and
the load is 120 watts?
A.
B.
C.
D.
0.1 amperes
10 amperes
p
12 amperes
132 amperes
p
61
T5D01
What formula is used to calculate current in
a circuit?
A. Current (I) equals voltage (E) multiplied
by resistance (R)
B. Current
C
(I)
( ) equals voltage (E)
( ) divided
i i
by resistance (R)
C Current (I) equals voltage (E) added to
C.
resistance (R)
q
voltage
g ((E)) minus
D. Current ((I)) equals
resistance (R)
62
T5D02
What formula is used to calculate voltage in
a circuit?
A. Voltage (E) equals current (I) multiplied
by resistance (R)
B. Voltage (E)
( ) equals current (I)
( ) divided
i i
by
resistance (R)
C Voltage (E) equals current (I) added to
C.
resistance (R)
g (E)
( ) equals
q
current ((I)) minus
D. Voltage
resistance (R)
63
T5D03
64
T5D04
What formula is used to calculate
resistance in a circuit?
A. Resistance (R) equals voltage (E)
multiplied by current (I)
B. Resistance
i
((R)) equals voltage (E)
( )
divided by current (I)
C Resistance (R) equals voltage (E) added
C.
to current (I)
q
voltage
g ((E)) minus
D. Resistance ((R)) equals
current (I)
A.
B.
C.
D.
65
What is the resistance of a circuit in which a
current of 3 amperes flows through a
resistor connected to 90 volts?
3 ohms
30 ohms
93 ohms
270 ohms
66
11
4/18/2012
T5D05
A.
B.
C.
D.
What is the resistance in a circuit for which
the applied voltage is 12 volts and the
current flow is 1.5 amperes?
18 ohms
0.125 ohms
8 ohms
13.5 ohms
T5D06
A.
B.
C.
D.
What is the resistance of a circuit that
draws 4 amperes from a 12-volt source?
3 ohms
16 ohms
48 ohms
8 ohms
67
T5D07
A.
B.
C.
D.
68
T5D08
What is the current flow in a circuit with an
applied voltage of 120 volts and a
resistance of 80 ohms?
9600 amperes
200 amperes
p
0.667 amperes
p
1.5 amperes
A.
B.
C.
D.
What is the current flowing through a 100100
ohm resistor connected across 200 volts?
20,000 amperes
0.5 amperes
p
2 amperes
p
100 amperes
69
T5D09
A.
B.
C.
D.
70
T5D10
What is the current flowing through a 2424
ohm resistor connected across 240 volts?
24,000 amperes
0.1 amperes
p
10 amperes
216 amperes
p
A.
B.
C.
D.
71
What is the voltage across a 2
2-ohm
ohm resistor
if a current of 0.5 amperes flows through it?
1 volt
0.25 volts
2.5 volts
1.5 volts
72
12
4/18/2012
T5D11
A.
B.
C.
D.
T5D12
What is the voltage across a 10
10-ohm
ohm
resistor if a current of 1 ampere flows
through it?
1 volt
10 volts
11 volts
9 volts
A.
B.
C.
D.
73
What is the voltage across a 10
10-ohm
ohm
resistor if a current of 2 amperes flows
through it?
8 volts
0.2 volts
12 volts
20 volts
74
13