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Transcript
Technician Licensing Class
“T4”
Presented by the
Plano Texas Stake
Plano, Texas
January 13, 2007
Amateur Radio Technician Class
Element 2Course Presentation
• ELEMENT 2 SUBELEMENTS
•
•
•
•
•
•
•
•
•
•
T1
T2
T3
T4
T5
T6
T7
T8
T9
T0
-
FCC Rules, station license responsibilities
Control operator duties
Operating practices
Radio and electronic fundamentals
Station setup and operation
Communications modes and methods
Special operations
Emergency and Public Service Communications
Radio waves, propagation, and antennas
Electrical and RF Safety
2
Radio and electronic fundamentals
T4A
 Names of electrical units: DC and AC
• Electrical current is measured in the following units:
 Amperes
• The name for the flow of electrons in an electric
circuit is:
 Current
• The name for a current that flows only in one
direction is:
 Direct Current (DC)
3
Radio and electronic fundamentals
T4A
 Names of electrical units: DC and AC
• Electrical Power is measured in the following units:
 Watt
• The standard unit of frequency is:
 Hertz
• The basic unit of resistance is:
 Ohm
• The name for current that reverses direction on a regular basis is:
 Alternating Current (AC)
4
Multimeter(s)
Multimeters will measure
Voltage, Current and
Resistance.
Be sure it is set properly to
read what is being
measured.
If it is set to the ohms
setting and voltage is
measured the meter could
be damaged!
Radio and electronic fundamentals
T4A
 Conductors and insulators (cont)
• Copper is a good electrical
conductor.
• Glass is a good electrical insulator.
• The term used to describe
opposition to current flow in
ordinary conductors such as wires
is: Resistance.
6
Radio and electronic fundamentals
Conductors and insulators
• Conductors




Gold
Silver
Copper
Aluminum
• Insulators




Air
Rubber
Plastic
Ceramic
T4A
Radio and electronic fundamentals
T4A
Two types of electricity:
• Direct Current - flows in 1 direction
 Battery
 1.5 to 2.5 volts per cell
 Car battery nominal 12 volts
 Measured strictly by amplitude
• Alternating Current - alternates direction
 Household
 Measured by
 Average Amplitude
 Frequency (cycles per second)(Hertz)
8
Alternating & Direct Current
V+
DC
0V
AC
Vtime
9
Radio and electronic fundamentals
T4A
 Electrical components
• An automobile battery usually supplies about
12 volts [DC].
• An Ammeter is an instrument used to measure
the flow of current in an electrical circuit.
• A Voltmeter is an instrument used to measure
Electromotive Force (EMF)
 between two points such as the poles of a battery.
10
Radio and electronic fundamentals
T4A
Ammeter
Power
Supply
Transceiver
11
Radio and electronic fundamentals
T4A
Ohmmeter
12
Radio and electronic fundamentals
T4A
Voltmeter
Power
Supply
Transceiver
13
Radio and electronic fundamentals
T4B
 Relationship between frequency and wavelength
• Wavelength is the term used for the distance a radio
wave travels during one complete cycle.
• The term Frequency describes the number of times
that an alternating current flows back and forth per
second.
• Sixty (60) hertz (Hz) means 60 cycles per second.
14
The Relationship of Frequency
and Wavelength
The distance a radio wave travels in
one cycle is called wavelength.
V+
One Cycle
0V
time
V-
One Wavelength
Radio and electronic fundamentals
T4B
 Relationship between frequency and wavelength
• The wavelength gets shorter as the frequency
increases.
• Wavelength in meters equals 300 divided by frequency
in megahertz.
• A radio wave travels through space at the speed of
light.
16
Radio and electronic fundamentals
T4B
 Identification of bands
• The property of a radio wave often used to identify the
different bands amateur radio operators use is the
physical length of the wave.
• The frequency range of the 2-meter band in the United
States is 144 to 148 MHz.
• The frequency range of the 6-meter band in the United
States is 50 to 54 MHz.
• The frequency range of the 70-centimeter band in the
United States is 420 to 450 MHz.
17
Radio and electronic fundamentals
T4B
 Names of frequency ranges, types of waves
• Voice frequencies are sound waves in the range
between 300 and 3000 Hertz.
• Electromagnetic waves that oscillate more than
20,000 times per second as they travel through
space are generally referred to as Radio
waves.
18
Radio and electronic fundamentals
T4C
 How radio works: receivers, transmitters, transceivers,
amplifiers, power supplies, types of batteries, service life
A Receiver is used to convert
radio signals into sounds we can
hear.
A Transmitter is used to
convert sounds from our voice
into radio signals.
A Receiver and Transmitter are
two devices combined into one
unit in a transceiver.
19
Radio and electronic fundamentals
T4C
 How radio works: receivers, transmitters, transceivers,
amplifiers, power supplies, types of batteries, service life (cont)
A Power Supply is the device
used to convert the alternating
current from a wall outlet into
low-voltage direct current.
An Amplifier is a device used
to increase the output of a 10
watt radio to 100 watts.
20
Radio and electronic fundamentals
 How radio works: receivers, transmitters, transceivers,
amplifiers, power supplies, types of batteries, service life
T4C
(cont)
A Lithium-ion battery offers the
longest life when used with a
hand-held radio, when comparing
battery types of the same physical
size.
The nominal voltage per cell of a
fully charged nickel-cadmium
battery is 1.2 volts.
A Carbon-zinc battery is not
designed to be re-charged.
21
Radio and electronic fundamentals
T4C
 How radio works: receivers, transmitters, transceivers,
amplifiers, power supplies, types of batteries, service life
(cont)
• In order to keep rechargeable batteries in good
condition and ready for emergencies:
 They must be inspected for physical damage and replaced if
necessary
 They should be stored in a cool and dry location
 They must be given a maintenance recharge at least every 6 months
All of these answers are correct
• The best way to get the most amount of energy from a
battery is to draw current from the battery at the slowest
22
rate needed.
Radio and electronic fundamentals
T4D
 Ohms law relationships
• The formula, Voltage (E) equals current (I)
multiplied by resistance (R).
= I*R
E
• The formula, Current (I) equals voltage (E)
divided by resistance (R).
= E/R
I
• The formula, Resistance (R) equals voltage (E)
divided by current (I).
R
= E/I
23
Meter Excercise
What circuit quantity
would meter A indicate?
+
Battery voltage
Meter B
R
Meter A
What circuit quantity
would meter B indicate?
The current flowing through
the resistor
24
Ohms Law
Electromotive Force, VOLTS
E
The flow of
Electrons,
AMPERES
I R
Resistance
to current flow,
OHMS
25
Radio and electronic fundamentals
T4D
 Ohms law relationships (cont)
• If I=3 amperes and E=90 volts.
 R = E/I = R = 90/3= 30
• If E=12 volts and I=1.5 amperes.
 R = E/I = R = 12/1.5= 8
• If E=120 volts and R=80 ohms.
 I = E/R = I = 120/80= 1.5
26
Radio and electronic fundamentals
 Ohms law relationships
T4D
(cont)
• If a current of 0.5 amperes flows through a 2 ohm resistor.
 E=I*R E = 0.5 * 2 = 1 volt
• If a current of 1 ampere flows through a 10 ohm resistor.
 E=I*R E = 1 * 10 = 10 volts
• If a current of 2 amperes flows through a 10 ohm resistor.
 E=I*R E = 2 * 10 = 20 volts
• Current through a 100 ohm resistor across 200 volts.
 I=E/R I = 200/100 = 2 amperes
• Current through a 24 ohm resistor across 240 volts.
 I=E/R I = 240/24 = 10 amperes
27
Radio and electronic fundamentals
T4D
 Ohms law relationships (cont)
• If a current of 0.5 amperes flows through a 2 ohm resistor.
 E=I*R
E = 0.5 * 2 = 1 volt
• If a current of 1 ampere flows through a 10 ohm resistor.
 E=I*R E = 1 * 10 = 10 volts
• If a current of 2 amperes flows through a 10 ohm resistor.
 E=I*R E = 2 * 10 = 20 volts
• Current through a 100 ohm resistor across 200 volts.
 I=E/R I = 200/100 = 2 amperes
• Current through a 24 ohm resistor across 240 volts.
 I=E/R I = 240/24 = 10 amperes
28
Power
Power is measured in
Watts
+
Meter B
R
P=ExI
Ohms law states E= I x R
Meter A
Substituting I x R for E in the power equation gives:
P = I x R x I = R x 2 x I = R x I2
So, for this circuit, the power consumed in the resistor
can be calculated by multiplying the value of the
resistor times the square of the reading of Meter B.
29
Radio and electronic fundamentals
T4E
Power calculations
• The unit used to describe
electrical power is the Watt.
• The formula: Power (P) equals
voltage (E) multiplied by current (I).
P=I*E
30
Radio and electronic fundamentals
• Power calculations
T4E
(cont)
• How much power is represented by a voltage of 13.8
volts DC and a current of 10 amperes.
 P = I * E P = 10 * 13.8 = 138 watts
• How much power is being used in a circuit when the
voltage is 120 volts DC and the current is 2.5 amperes.
 P = I * E P = 2.5 * 120 = 300 watts
31
Radio and electronic fundamentals
T4E
 Power calculations (cont)
• You can you determine how many watts are being
drawn [consumed] by your transceiver when you are
transmitting by measuring the DC voltage at the
transceiver and multiplying by the current drawn when
you transmit.
• How many amperes is flowing in a circuit when the
applied voltage is 120 volts DC and the load is 1200
watts.
• I = P/E I = 1200/120 = 10 amperes.
32
Ohm’s law formulas
33
Metric Prefixes
Metric
Exponent
English
Tera
Giga
Mega
1012
109
106
Trillion
Billion
Million
Kilo
Centi
Milli
Micro
Nano
Pico
103
10-2
10-3
10-6
10-9
10-12
Thousand
Hundredth
Thousandth
Millionth
Billionth
Trillionth
34
Radio and electronic fundamentals
T4
 Units, kilo, mega, milli, micro
• One thousand volts is equal to one kilovolt.
• Another way to specify the frequency of a radio signal that is
oscillating at 1,500,000 Hertz is 1500 kHz
 [or 1.5 megahertz]
• 1500 milliamperes is the same as 1.5 amperes.
• A hand-held transceiver that has an output power of 500
milliwatts can otherwise be said to output 0.5 watts.
• One one-millionth of a volt is equal to one microvolt.
35
Take aways
•
•
•
•
•
•
Unit of current… amperes
Electron flow is current
Current flowing in one direction is DC
Unit of power … Watt
Unit of frequency … Hertz
Unit of resistance … Ohm
• Current that reverses direction is AC
36
Take aways
(cont)
• Copper is a good conductor
• Glass is a good insulator
• Opposition to current flow …. Resistance
• Conductors…gold, silver, copper, aluminum
• Insulators…air, rubber, plastic, ceramic
37
Take aways
(cont)
• Car battery … 12 volts DC
• DC measured by amplitude
• AC measured by Average Amplitude
• Ammeter measures current
• Volt meter measures voltage
• Sixty hertz means 60 cycles per second
38
Take aways
(cont)
• Frequency describes number of times AC flows back and
forth per second
• Wavelength is distance a radio wave travels during one
complete cycle
• Frequency increases as wavelength gets shorter
• Wavelength in meters equals 300 divided by frequency in
MHz
• Radio waves travel at speed of light
39
Take aways
(cont)
• Bands identified by physical length (or wavelength)
• 2-meter band 144 to 148 MHz
• 6-meter band 50 to 54 MHz
• 70-centimeter band 420 to 450 MHz
• Sound waves 300 to 3000 Hertz
• Radio waves are Electromagnetic and are 20,000 cycles
per second and higher
40
Take aways
(cont)
• Receiver converts radio signals to audio
• Transmitter converts sound into radio waves
• Transceiver is two devices in one, receiver and
transmitter
• Power supply converts AC to DC.
• Amplifier increases power output
• Lithium-ion battery offers longest life in HT’s
• Ni-Cad per cell voltage is 1.2 volts
• Carbon-zinc battery cannot be re-charged
41
Take aways
(cont)
• Keep re-chargeable batteries in good
condition for emergencies
 Inspect for damage
 Store in cool and dry location
 Given maintenance recharge every 6
months
All of these answers are correct
• Slowest rate of current drain gives most
amount of energy
42
Take aways
(cont)
Ohms Law
Power calculations
43
Take aways
(cont)
• One kilovolt is one thousand volts
• 1500 KHz is 1,500,000 Hertz
• 1.5 amps is 1500 milliamperes
• 500 milliwatts is 0.5 watts
• One microvolt is one one-millionth of a volt
44
Element 2 Technician Class
Question Pool
T4
Valid July 1, 2006
Through
June 30, 2010
45
T4A01
Electrical current is measured in
which of the following units?
A.
B.
C.
D.
Volts
Watts
Ohms
Amperes
46
T4A02
Electrical Power is measured in
which of the following units?
A.
B.
C.
D.
Volts
Watts
Ohms
Amperes
47
T4A03
What is the name for the flow of
electrons in an electric circuit?
A.
B.
C.
D.
Voltage
Resistance
Capacitance
Current
48
T4A04
What is the name of a current that
flows only in one direction?
A.
B.
C.
D.
An alternating current
A direct current
A normal current
A smooth current
49
T4A05
A.
B.
C.
D.
What is the standard unit of
frequency?
The megacycle
The Hertz
One thousand cycles per second
The electromagnetic force
50
T4A06
How much voltage does an
automobile battery usually supply?
A.
B.
C.
D.
About 12 volts
About 30 volts
About 120 volts
About 240 volts
51
T4A07 What is the basic unit of resistance?
A.
B.
C.
D.
The volt
The watt
The ampere
The ohm
52
T4A08 What is the name of a current that
reverses direction on a regular basis?
A.
B.
C.
D.
An alternating current
A direct current
A circular current
A vertical current
53
T4A09
Which of the following is a good
electrical conductor?
A.
B.
C.
D.
Glass
Wood
Copper
Rubber
54
T4A10
Which of the following is a good
electrical insulator?
A.
B.
C.
D.
Copper
Glass
Aluminum
Mercury
55
T4A11
A.
B.
C.
D.
What is the term used to describe
opposition to current flow in
ordinary conductors such as wires?
Inductance
Resistance
Counter EMF
Magnetism
56
T4A12
What instrument is used to
measure the flow of current in an
electrical circuit?
A.
B.
C.
D.
Frequency meter
SWR meter
Ammeter
Voltmeter
57
T4A13
What instrument is used to measure
Electromotive Force (EMF) between two
points such as the poles of a battery?
A.
B.
C.
D.
Magnetometer
Voltmeter
Ammeter
Ohmmeter
58
T4B01
What is the name for the distance a radio
wave travels during one complete cycle?
A.
B.
C.
D.
Wave speed
Waveform
Wavelength
Wave spread
59
T4B02
What term describes the number of times
that an alternating current flows back and
forth per second?
A.
B.
C.
D.
Pulse rate
Speed
Wavelength
Frequency
60
T4B03 What does 60 hertz (Hz) mean?
A.
B.
C.
D.
6000 cycles per second
60 cycles per second
6000 meters per second
60 meters per second
61
T4B04
Electromagnetic waves that oscillate more than
20,000 times per second as they travel
through space are generally referred to as what?
A.
B.
C.
D.
Gravity waves
Sound waves
Radio waves
Gamma radiation
62
T4B05
How fast does a radio wave travel
through space?
A. At the speed of light
B. At the speed of sound
C. Its speed is inversely proportional to its
wavelength
D. Its speed increases as the frequency
increases
63
T4B06
How does the wavelength of a radio wave
relate to its frequency?
A. The wavelength gets longer as the
frequency increases
B. The wavelength gets shorter as the
frequency increases
C. There is no relationship between
wavelength and frequency
D. The wavelength depends on the
bandwidth of the signal
64
T4B07
What is the formula for converting
frequency to wavelength in meters?
A. Wavelength in meters equals frequency in
Hertz multiplied by 300
B. Wavelength in meters equals frequency in
Hertz divided by 300
C. Wavelength in meters equals frequency in
megahertz divided by 300
D. Wavelength in meters equals 300 divided
by frequency in megahertz
65
T4B08
A.
B.
C.
D.
What are sound waves in the range
between 300 and 3000 Hertz called?
Test signals
Ultrasonic waves
Voice frequencies
Radio frequencies
66
T4B09
What property of a radio wave is often
used to identify the different bands
amateur radio operators use?
A. The physical length of the wave
B. The magnetic intensity of the wave
C. The time it takes for the wave to travel
one mile
D. The voltage standing wave ratio of the
wave
67
T4B10
What is the frequency range of the
2 meter band in the United States?
A.
B.
C.
D.
144 to 148 MHz
222 to 225 MHz
420 to 450 MHz
50 to 54 MHz
68
T4B11
What is the frequency range of the
6 meter band in the United States?
A.
B.
C.
D.
144 to 148 MHz
222 to 225 MHz
420 to 450 MHz
50 to 54 MHz
69
T4B12
What is the frequency range of the
70 centimeter band in the United States?
A.
B.
C.
D.
144 to 148 MHz
222 to 225 MHz
420 to 450 MHz
50 to 54 MHz
70
T4C01 What is used to convert radio
signals into sounds we can hear?
A.
B.
C.
D.
Transmitter
Receiver
Microphone
Antenna
71
T4C02 What is used to convert sounds from
our voice into radio signals?
A.
B.
C.
D.
Transmitter
Receiver
Speaker
Antenna
72
T4C03 What two devices are combined into
one unit in a transceiver?
A.
B.
C.
D.
Receiver, transmitter
Receiver, transformer
Receiver, transistor
Transmitter, deceiver
73
T4C04
What device is used to convert the
alternating current from a wall outlet into
low-voltage direct current?
A.
B.
C.
D.
Inverter
Compressor
Power Supply
Demodulator
74
T4C05
What device is used to increase the
output of a 10 watt radio to 100 watts?
A.
B.
C.
D.
Amplifier
Power supply
Antenna
Attenuator
75
T4C06
Which of the battery types listed below offers the longest
life when used with a hand-held radio,
assuming each
battery is the same physical size?
A.
B.
C.
D.
Lead-acid
Alkaline
Nickel-cadmium
Lithium-ion
76
T4C07
What is the nominal voltage per cell of
a fully charged nickel-cadmium battery?
A.
B.
C.
D.
1.0 volts
1.2 volts
1.5 volts
2.2 volts
77
T4C08 What battery type on this list is not
designed to be re-charged?
A.
B.
C.
D.
Nickel-cadmium
Carbon-zinc
Lead-acid
Lithium-ion
78
T4C09
What is required to keep rechargeable
batteries in good condition and ready
for emergencies?
A. They must be inspected for physical
damage and replaced if necessary
B. They should be stored in a cool and dry
location
C. They must be given a maintenance
recharge at least every 6 months
D. All of these answers are correct
79
T4C10
What is the best way to get the most
amount of energy from a battery?
A. Draw current from the battery as rapidly
as possible
B. Draw current from the battery at the
slowest rate needed
C. Reverse the leads when the battery
reaches the 1/2 charge level
D. Charge the battery as frequently as
possible
80
T4D01 What formula is used to calculate
current in a circuit?
A. Current (I) equals voltage (E) multiplied
by resistance (R)
B. Current (I) equals voltage (E) divided by
resistance (R)
C. Current (I) equals voltage (E) added to
resistance (R)
D. Current (I) equals voltage (E) minus
resistance (R)
81
T4D02 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 by
resistance (R)
C. Voltage (E) equals current (I) added to
resistance (R)
D. Voltage (E) equals current (I) minus
resistance (R)
82
T4D03 What formula is used to calculate
resistance in a circuit?
A. Resistance (R) equals voltage (E)
multiplied by current (I)
B. Resistance (R) equals voltage (E) divided
by current (I)
C. Resistance (R) equals voltage (E) added
to current (I)
D. Resistance (R) equals voltage (E) minus
current (I)
83
T4D04
What is the resistance of a circuit when a
current of 3 amperes flows through a
resistor connected to 90 volts?
A.
B.
C.
D.
3 ohms
30 ohms
93 ohms
270 ohms
84
T4D05
What is the resistance in a circuit
where the applied voltage is 12 volts
and the current flow is 1.5 amperes?
A.
B.
C.
D.
18 ohms
0.125 ohms
8 ohms
13.5 ohms
85
T4D06
What is the current flow in a circuit
with an applied voltage of 120 volts
and a resistance of 80 ohms?
A.
B.
C.
D.
9600 amperes
200 amperes
0.667 amperes
1.5 amperes
86
T4D07
What is the voltage across the resistor
if a current of 0.5 amperes flows through
a 2 ohm resistor?
A.
B.
C.
D.
1 volt
0.25 volts
2.5 volts
1.5 volts
87
T4D08
What is the voltage across the resistor
if a current of 1 ampere flows through
a 10 ohm resistor?
A.
B.
C.
D.
10 volts
1 volt
11 volts
9 volts
88
T4D09
What is the voltage across the resistor
if a current of 2 amperes flows through
a 10 ohm resistor?
A.
B.
C.
D.
20 volts
0.2 volts
12 volts
8 volts
89
T4D10
What is the current flowing through a 100
ohm resistor connected across 200 volts?
A.
B.
C.
D.
20,000 amperes
0.5 amperes
2 amperes
100 amperes
90
T4D11
What is the current flowing through a 24
ohm resistor connected across 240 volts?
A.
B.
C.
D.
24,000 amperes
0.1 amperes
10 amperes
216 amperes
91
T4E01
What unit is used to describe
electrical power?
A.
B.
C.
D.
Ohm
Farad
Volt
Watt
92
T4E02
What is the formula used to
calculate electrical power?
A. Power (P) equals voltage (E) multiplied
by current (I)
B. Power (P) equals voltage (E) divided by
current (I)
C. Power (P) equals voltage (E) minus
current (I)
D. Power (P) equals voltage (E) plus
current (I)
93
T4E03
How much power is represented by
a voltage of 13.8 volts and a current
of 10 amperes?
A.
B.
C.
D.
138 watts
0.7 watts
23.8 watts
3.8 watts
94
T4E04
How much power is being used in a
circuit when the voltage is 120 volts and
the current is 2.5 amperes?
A.
B.
C.
D.
1440 watts
300 watts
48 watts
30 watts
95
T4E05
How can you determine how many
watts are being drawn by your transceiver
when you are transmitting?
A. Measure the DC voltage and divide it
by 60 Hz
B. Check the fuse in the power leads to
see what size it is
C. Look in the Radio Amateur's
Handbook
D. Measure the DC voltage at the
transceiver and multiply by the
current drawn when you transmit
96
T4E06
How many amperes are flowing in a
circuit when the applied voltage is 120V
and the load is 1200 watts?
A.
B.
C.
D.
20 amperes
10 amperes
120 amperes
5 amperes
97
T4E07
How many milliamperes is the same
as 1.5 amperes?
A.
B.
C.
D.
15 milliamperes
150 milliamperes
1500 milliamperes
15000 milliamperes
98
T4E08
What is another way to specify the
frequency of a radio signal that is
oscillating at 1,500,000 Hertz?
A.
B.
C.
D.
1500 kHz
1500 MHz
15 GHz
150 kHz
99
T4E09
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
100
T4E10 How many volts are equal to
one microvolt?
A.
B.
C.
D.
one one-millionth of a volt
one million volts
one thousand kilovolts
one one-thousandth of a volt
101
T4E11
How many watts does a hand-held
transceiver put out if the output
power is 500 milliwatts?
A.
B.
C.
D.
0.02 watts
0.5 watts
5 watts
50 watts
102