Technician Licensing Class “T0”

Technician Licensing Class“T0”

Presented by thePlano Texas Stake

Plano, Texas

February 3, 2007

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Amateur Radio Technician ClassElement 2

• ELEMENT 2 SUBELEMENTS

• T1 - FCC Rules, station license responsibilities• T2 - Control operator duties• T3 - Operating practices• T4 - Radio and electronic fundamentals• T5 - Station setup and operation• T6 - Communications modes and methods• T7 - Special operations• T8 - Emergency and Public Service Communications• T9 - Radio waves, propagation, and antennas• T0 - Electrical and RF Safety

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Electrical and RF Safety T0A

AC power circuits, Electrical code compliance• A few good ways to guard against electrical shock at

your station are: Use 3-wire cords and plugs for all AC powered

equipment Use a ground-fault interrupter at each electrical

outlet Connect all AC powered station equipment to a

common groundAll of these answers are correct

• The most important thing to consider when installing an emergency disconnect switch at your station is for everyone to know where it is and how to use it.

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Three Wire Plug

In a three wire AC electrical line:

Black is HOT

White is NEUTRAL

Green is Chassis Ground

Breaker box Service Disconnect on left.

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Ground Everything

For best protection from electrical shock all equipment should be connected to a common ground.

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Hazardous voltages• The commonly accepted value for the lowest voltage

that can cause a dangerous electric shock is 30 volts. (Note: Lower voltages can be just as dangerous where conditions result in lower levels of resistance and thus current levels approaching 100 miliamperes.)

• The lowest amount of electrical current flowing through the human body that is likely to cause death is 100 milliamperes.A hazard might still exist in a power supply when it is turned off and disconnected. If you aren’t careful you might receive an electric shock from stored charge in large capacitors.

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Fuses and circuit breakers• The purpose of a fuse in an electrical circuit is

to interrupt power in case of overload.• If you install a 20-ampere fuse in your

transceiver in the place of a 5-ampere fuse excessive current could cause a fire. (Note: If it didn’t cause a fire, it still could result in damage to the equipment.)

Grounding• Ground is connected to the green wire in a

three-wire electrical plug.

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Lightning protection• The precautions that should be taken when a

lightning storm is expected are: Disconnect the antenna cables from your station

and move them away from your radio equipment Unplug all power cords from AC outlets Stop using your radio equipment and move to

another room until the storm passesAll of these answers are correct

• Fire prevention is the most important reason to have a lightning protection system for your amateur radio station.

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Battery safety• One way to recharge a 12-volt battery if the

commercial power is out is to connect the battery to a car's battery and run the engine.

• If a storage battery is charged or discharged too quickly it could overheat and give off dangerous gas or explode.

• The hazards that are presented by a conventional 12-volt storage battery are: It contains dangerous acid that can spill and

cause injury Short circuits can damage wiring and possibly

cause a fire Explosive gas can collect if not properly ventedAll of these answers are correct

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Electrical and RF Safety T0B

Antenna installation• An important consideration when putting up an

antenna is make sure people cannot accidentally come into contact with it.

• The maximum allowed height with regard to nearby airports must be considered when erecting an antenna near an airport.

Tower safety• You should wear a hard hat and safety glasses if

you are on the ground helping someone work on an antenna tower in order to protect your head and eyes in case something accidentally falls from the tower.

• A good precaution to observe before climbing an antenna tower is to put on your safety belt and safety glasses.

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Tower safety (cont)

• You should do all of the following before you climb a tower: Arrange for a helper or observer Inspect the tower for damage or loose

hardware Make sure there are no electrical storms nearbyAll of these answers are correct

• Guy wires for an antenna tower should be installed in accordance with the tower manufacturer's instructions.

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Tower safety (cont)

• The most important safety rule to remember when using a crank-up tower is a crank-up tower should never be climbed unless it is in the fully lowered position.

• Stainless steel hardware is used on many antennas instead of other metals because stainless steel parts are much less likely to corrode.

• A separate 8 foot long ground rods for each tower leg, bonded to the tower and each other is considered to be an adequate ground for a tower.

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Overhead power lines

• The most important safety precaution to observe when putting up an antenna tower is look for and stay clear of any overhead electrical wires.

• A safe distance from a power line to allow when installing an antenna is so that if the antenna falls unexpectedly, no part of it can come closer than 10 feet to the power wires.

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Electrical and RF Safety T0C

RF hazards, RF heating hazards, Proximity to antennas, Hand held safety

• VHF and UHF radio signals are non-ionizing radiation.

• Radio waves can cause injury to the human body only if the combination of signal strength and frequency cause excessive power to be absorbed.

• If a person accidentally touched your antenna while you were transmitting they might receive a painful RF burn injury.

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Radiation exposure, exposure to others• The factors that affect the RF exposure of

people near an amateur transmitter are: Frequency and power level of the RF field Distance from the antenna to a person Radiation pattern of the antennao All of these answers are correct

• The frequency of an RF source must be considered when evaluating RF radiation exposure because the human body absorbs more RF energy at some frequencies than others.

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Radiation exposure, exposure to others (cont)

• Some actions amateur operators might take to prevent exposure to RF radiation in excess of FCC supplied limits include: Alter antenna patterns Relocate antennas Change station parameters such as frequency or

power All of these answers are correct

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Recognized safe power levels• The maximum power level that an amateur

radio station may use at frequencies above 30 MHz before an RF exposure evaluation is required is 50 watts PEP at the antenna.

• You can determine that your station complies with FCC RF exposure regulations: By calculation based on FCC OET Bulletin 65 By calculation based on computer modeling By measurement of field strength using

calibrated equipmentAll of these choices are correct

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Recognized safe power levels (cont)

• Milliwatts per square centimeter is the unit of measurement used to measure RF radiation exposure.

• The duty cycle is one of the factors used to determine safe RF radiation exposure levels because it takes into account the amount of time the transmitter is operating.

• You make sure your station stays in compliance with RF safety regulations by re-evaluating the station whenever an item of equipment is changed.

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Take Aways

• Guard against electrical shock 3-wire plugs Ground-fault Common ground

• Emergency disconnect…tell everyone where it is.• Lowest voltage for shock … 30 volts• Lowest current is … 100 milliamperes• Stored charge in large capacitors can cause shock

with power supply off• Fuses interrupt power in overload• 20 amp replacing a 5 amp … potential fire• Green wire of 3-wire is ground

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Take Aways (cont)

• Lightning protection Disconnect antenna Unplug power from AC Stop using equipment… move to another room

• Fire prevention … most important reason for lightning protection

• Recharge 12-volt battery … connect to car … run engine

• Storage battery charge or discharge too quickly … overheat/explode

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Take Aways (cont)

• 12-volt hazards Contain acid … spill .. Cause injury Short circuits … damage wiring … fire Explosive gas if not vented

• Antenna location … away from people• Hard hat … safety glasses … on ground

helping• Use safety belt & safety glasses before

climbing tower

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Take Aways (cont)

• Before climbing a tower Arrange helper/observer Inspect damage/loose hardware No electrical storms nearby

• Guy wires …. Install per manufacturer• Never climb a crank-up tower extended• Stainless hardware much less likely to

corrode• 8 foot ground rods … per tower leg …

bonded to tower

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Take Aways (cont)

• Stay clear of overhead electric wires … putting up tower

• Safe distance … if falls … no closer than 10 feet

• VHF/UHF non-ionizing radiation• Excessive power absorbed can cause injury

to body• Touch antenna during transmission …

possible RF burn• Body absorbs more RF energy at some

frequencies than others …. Source must be considered

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Take Aways (cont)

• Factors affecting RF exposure … in excess of FCC limits Frequency and power level Distance from antenna Radiation pattern of antenna

• Actions to prevent exposure Alter antenna patterns Relocate antenna Change station parameters … power or

frequency

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Take Aways (cont)

• RF exposure above 30 MHz … 50 watts PEP at antenna

• Determine FCC RF exposure FCC OET Bulletin 65 Calculations on computer modeling Field strength meter

• Milliwatts sq/centimeter … measure RF radiation exposure

• Duty cycle … amount of time transmitter is operating

• Change equipment … re-evaluate RF safety regs to stay in compliance

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Element 2 Technician Class Question Pool

T0

Valid July 1, 2006

Through

June 30, 2010

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T0A01 What is a commonly accepted value for the lowest voltage that can cause

a dangerous electric shock?

A. 12 voltsB. 30 voltsC. 120 voltsD. 300 volts

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T0A02 What is the lowest amount of electrical current flowing through the human body that is likely to cause death?

A. 10 microamperes B. 100 milliamperesC. 10 amperesD. 100 amperes

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T0A03 What is connected to the green wire in a three-wire electrical plug?

A. Neutral B. Hot C. Ground D. The white wire

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T0A04 What is the purpose of a fuse in an electrical circuit?

A. To make sure enough power reaches the circuit

B. To interrupt power in case of overload

C. To prevent television interference D. To prevent shocks

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T0A05 What might happen if you install a 20-ampere fuse in your transceiver in

the place of a 5-ampere fuse?

A. The larger fuse would better protect your transceiver from using too much current

B. The transceiver will run coolerC. Excessive current could cause a fire D. The transceiver would not be able to

produce as much RF output

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T0A06 What is a good way to guard against electrical shock at your station?

A. Use 3-wire cords and plugs for all AC powered equipment

B. Connect all AC powered station equipment to a common ground

C. Use a ground-fault interrupter at each electrical outlet

D. All of these answers are correct

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T0A07 What is the most important thing to consider when installing an emergency disconnect switch at your station?

A. It must always be as near to the operator as possible

B. It must always be as far away from the operator as possible

C. Everyone should know where it is and how to use it

D. It should be installed in a metal box to prevent tampering

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T0A08 What precautions should be taken when a lightning storm is expected?

A. Disconnect the antenna cables from your station and move them away from your radio equipment

B. Unplug all power cords from AC outletsC. Stop using your radio equipment and

move to another room until the storm passes


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T0A09 What is one way to recharge a 12-volt battery if the commercial power is out?

A. You cannot recharge a battery unless the power is back on

B. Add water to the battery C. Connect the battery to a car's battery

and run the engine D. Take your battery to the utility

company for a recharge

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T0A10 What kind of hazard is presented by a conventional 12-volt storage battery?

A. It contains dangerous acid that can spill and cause injury

B. Short circuits can damage wiring and possibly cause a fire

C. Explosive gas can collect if not properly vented


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T0A11 What can happen if a storage battery is charged or discharged too quickly?

A. The battery could overheat and give off dangerous gas or explode

B. The terminal voltage will oscillate rapidly

C. The warranty will be voidedD. The voltage will be reversed

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T0A12 What is the most important reason to have a lightning protection system

for your amateur radio station?

A. Lower insurance ratesB. Improved receptionC. Fire preventionD. Noise reduction

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T0A13 What kind of hazard might exist in a power supply when it is turned off and disconnected?

A. Static electricity could damage the grounding system

B. Circulating currents inside the transformer might cause damage

C. The fuse might blow if you remove the cover

D. You might receive an electric shock from stored charge in large capacitors

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T0B01 Why should you wear a hard hat and safety glasses if you are on the ground helping someone work on an antenna tower?

A. It is required by FCC rules B. To keep RF energy away from your

head during antenna testingC. To protect your head and eyes in case

something accidentally falls from the tower

D. It is required by the electrical code

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T0B02 What is a good precaution to observe before climbing an antenna tower?

A. Turn on all radio transmittersB. Remove all tower grounding

connectionsC. Put on your safety belt and safety

glassesD. Inform the FAA and the FCC that

you are working on a tower

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T0B03 What should you do before you climb a tower?

A. Arrange for a helper or observerB. Inspect the tower for damage or

loose hardwareC. Make sure there are no electrical

storms nearbyD. All of these answers are correct

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T0B04 What is an important consideration when putting up an antenna?

A. Carefully tune it for a low SWRB. Make sure people cannot accidentally

come into contact with itC. Make sure you discard all packing

material in a safe placeD. Make sure birds can see it so they

don't fly into it

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T0B05 What must be considered when erecting an antenna near an airport?

A. The maximum allowed height with regard to nearby airports

B. The possibility of interference to aircraft radios

C. The radiation angle of the signals it produces

D. The polarization of signal to be radiated

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T0B06 What is the most important safety precaution to observe when putting up an antenna tower?

A. Install steps on the tower for safe climbing

B. Insulate the base of the tower to avoid lightning strikes

C. Ground the base of the tower to prevent lightning strikes

D. Look for and stay clear of any overhead electrical wires

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T0B07 How should the guy wires for an antenna tower be installed?

A. So each guy wire anchor point has an even number of wires

B. So that no guy wire is more than 25 feet long

C. Each guy wire must be pulled as tight as possible

D. In accordance with the tower manufacturer's instructions

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T0B08 What is a safe distance from a power line to allow when installing an antenna?

A. Half the width of your property unless the wires are at least 23 feet high

B. 12.5 feet in most metropolitan areas C. 36 meters plus 1/2 wavelength at the

operating frequencyD. So that if the antenna falls

unexpectedly, no part of it can come closer than 10 feet to the power wires

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T0B09 What is the most important safety rule to remember when using a crank-up tower?

A. This type of tower must never be paintedB. Crank up towers must be raised and

lowered frequently to keep them properly lubricated

C. Winch cables must be specially rated for use on this type of tower

D. A crank-up tower should never be climbed unless it is in the fully lowered position

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T0B10 Why is stainless steel hardware used on many antennas instead of other metals?

A. Stainless steel is a better electrical conductor

B. Stainless steel weighs less than other metals

C. Stainless steel parts are much less likely to corrode

D. Stainless steel costs less than other metals

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T0B11 What is considered to be an adequate ground for a tower?

A. A single 4 foot ground rod, driven into the earth no more than 12 inches from the base

B. A screen of 120 radial wiresC. Separate 8 foot long ground rods for each

tower leg, bonded to the tower and each other

D. A connection between the tower base and a cold water pipe

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T0C01 What type of radiation are VHF and UHF radio signals?

A. Gamma radiationB. Ionizing radiationC. Alpha radiationD. Non-ionizing radiation

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T0C02 When can radio waves cause injury to the human body?

A. Only when the frequency is below 30 MHzB. Only if the combination of signal strength

and frequency cause excessive power to be absorbed

C. Only when the frequency is greater than 30 MHz

D. Only when transmitter power exceeds 50 watts

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T0C03 What is the maximum power level that an amateur radio station may use at frequencies above 30 MHz before an RF exposure evaluation is required?

A. 1500 watts PEP transmitter outputB. 1 watt forward powerC. 50 watts PEP at the antennaD. 50 watts PEP reflected power

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T0C04 What factors affect the RF exposure of people near an amateur transmitter?

A. Frequency and power level of the RF field

B. Distance from the antenna to a person

C. Radiation pattern of the antennaD. All of these answers are correct

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T0C05 Why must the frequency of an RF source be considered when evaluating RF radiation exposure?

A. Lower frequency RF fields have more energy than higher frequency fields

B. Lower frequency RF fields do not penetrate the human body

C. Higher frequency RF fields are transient in nature and do not affect the human body

D. The human body absorbs more RF energy at some frequencies than others

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T0C06 How can you determine that your station complies with FCC RF exposure regulations?

A. By calculation based on FCC OET Bulletin 65

B. By calculation based on computer modeling

C. By measurement of field strength using calibrated equipment

D. All of these choices are correct

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T0C07 What could happen if a person accidentally touched your antenna while you were transmitting?

A. Touching the antenna could cause television interference

B. They might receive a painful RF burn injury

C. They would be able to hear what you are saying

D. Nothing

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T0C08 What action might amateur operators take to prevent exposure to RF radiation in excess of FCC supplied limits?

A. Alter antenna patternsB. Relocate antennasC. Change station parameters such as

frequency or powerD. All of these answers are correct

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T0C09 How can you make sure your station stays in compliance with RF safety regulations?

A. Compliance is not necessary B. By re-evaluating the station whenever

an item of equipment is changed C. By making sure your antennas have a

low SWR D. By installing a low pass filter

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T0C10 Which of the following units of measurement is used to measure RF radiation exposure?

A. Milliwatts per square centimeterB. Megohms per square meter C. Microfarads per footD. Megahertz per second

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T0C11 Why is duty cycle one of the factors used to determine safe RF radiation exposure levels?

A. It takes into account the amount of time the transmitter is operating

B. It takes into account the transmitter power supply rating

C. It takes into account the antenna feed line loss

D. It takes into account the thermal effects of the final amplifier

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Practice exams on the Internet

• HTTP://www.QRZ.Com/p/testing.pl

• HTTP://www.W8MHB.Com/Exam

• HTTP://www.AA9PW.Com/Radio

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Yipee!

That was the last slide!

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We’ve covered the content …

• Are there any questions?

• Any special areas to go back over quickly?

• Ask about Exam Dates, times, and Locations

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Now that I am an Amateur Radio Now that I am an Amateur Radio Operator, What Do I Do?Operator, What Do I Do?

• Support Amateur Radio locally. Be Support Amateur Radio locally. Be involved in local clubs and involved in local clubs and associations.associations.

• Get involved in community service Get involved in community service through your local ARES group.through your local ARES group.

• Join the American Radio Relay League Join the American Radio Relay League (ARRL)(ARRL)

More importantly, get on the air More importantly, get on the air and say something!and say something!

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Why join the ARRL?Why join the ARRL?

• Since 1914 the American Since 1914 the American Radio Relay League has Radio Relay League has represented the interests represented the interests of Radio Amateurs before of Radio Amateurs before the FCC and Congress.the FCC and Congress.

• QST magazine is an QST magazine is an excellent educational tool, excellent educational tool, full of interesting articles full of interesting articles and fun projects.and fun projects.

• Members-Only Web Access • Technical Information

Service (TIS)• Ham Radio Equipment

Insurance• ARRL Field Organization• http://www.ARRL.Org

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This Completes the This Completes the Course…Course…

……and begins a and begins a worldwide worldwide journey that will journey that will last you a last you a lifetime.lifetime.

Enjoy your new Enjoy your new hobby!hobby!

Technician Licensing Class “T0”

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Transcript of Technician Licensing Class “T0”