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1. Definitions. Explain what radio is.  Include in your explanation: the differences between broadcast radio and hobby radio, and the differences between broadcasting and two-way communicating.  Also discuss broadcast and amateur radio call signs and using phonetics.
2. Radio Waves. Sketch a diagram showing how radio waves travel locally and around the world.  How do the broadcast radio stations WWV and WWVH help determine what you will hear when you listen to a radio?
3. Radio Spectrum. Do the following:
• Draw a chart of the electromagnetic spectrum covering 100 kilohertz (kHz) to 1000 megahertz (MHz).
• Label the LF, MF, VHF, UHF, and microwave portions of the spectrum on your diagram.
• Locate on your chart at least eight radio services such as AM and FM commercial broadcast, CB, television, amateur radio (at least four ham radio bands), and police.
• Discuss why some radio stations are called "DX" and others are called "local".  Explain who the FCC and ITU are.
4. Radio Waves. Explain how radio waves carry information.  Include in your explanation: transceiver, transmitter, amplifier, and antenna.
5. Safety. Learn the safety precautions for working with radio gear, particularly DC and RF grounding.
6. Diagrams and Symbols. Do the following:
• Explain the difference between a block diagram and a schematic diagram.
• Draw a block diagram that includes a transceiver, amplifier, microphone, antenna, and feed line.
• Explain the differences between an open circuit, a closed circuit, and a short circuit.
• Draw ten schematic symbols.  Explain what three of the represented parts do.  Find three electrical components to match to three of these symbols.
7. Operating. Do the following:
• Describe some of the activities that amateur radio operators can do on the air, once they have earned an amateur radio license.
• Carry on a 10 minute real or simulated radio contact using voice or Morse code; use proper call signs, Q signals, and abbreviations.  (Licensed ham radio operators may substitute five QSL cards as evidence of contacts with amateur radio operators from at least three different call districts.)
• With the help of a local amateur radio operator, talk to and properly log at least two Morse code radio contacts.  Record signal reports.  Explain how often amateur radio operators must give their call signs during a radio contact.
• Explain at least five Q signals or amateur radio terms you hear while listening.
• Explain some differences between the Novice Class and Technician Class license requirements and privileges.  Explain who gives amateur radio exams.
• Explain how you would make an emergency call using voice or Morse code.  Tell why the FCC has an amateur radio service.
• Explain handheld transceivers versus home "base" stations.  Explain about mobile amateur radios and amateur radio repeaters.
8. Visit a radio installation approved in advance by your counselor (ham radio station, broadcast station, or public service communications center, for example). Discuss what types of equipment you saw in use, how it was used, what types of licenses are required to operate and maintain the equipment, and the purpose of the station.

    Radio is the practice or science of communicating over distance by converting sounds or signals into electromagnetic waves and transmitting these directly through space without connecting wires, to a receiving set, which changes them back to sounds or signals.

    Broadcasting is one-way communications such as the one-way transmissions from commercial AM, FM, and TV stations to provide information or entertainment to the receiving public.

    Two-way communications is communicating by transmitting and receiving by both stations, so a two way conversion can take place.  Fire, police, marine, and amateur communications are examples of two-way communications services.

    Amateur Radio or "Ham" Radio is a scientific hobby providing two-way communications by private short wave radio around the world, or by VHF/UHF radio locally.  It is for non-commercial use by individuals licensed by the FCC.  Amateurs communicate using many modes--voice, Morse code, radio teletype, amateur television, and packet radio to name a few popular ones.

    Call Signs--Amateur radio operators are issued a unique identifying call sign by their government.  Each country is allocated a certain group of beginning letters (prefixes) which identifies the country.  For example, British amateur call signs begin with the letter "G", French call signs begin with the letter "F", and American call signs begin with either a "W", "K", "N", or "A".  If W, K, or N, the prefix may consist of just that single letter, or it may have a second letter added.  Examples of valid prefixes are W, WB, K, KH, etc.  On the other hand, the "A" prefix block is divided among several countries, so a second character is required in the prefix.  Valid American "A" prefixes range from AA through AL.  American call letter prefixes are followed by a single number, and a suffix consisting of one or more letters.  For example, W4DC is a valid U.S. amateur call sign.

    Phonetics--Amateurs worldwide use phonetics (words which stand for the letter they begin with) to better get their call sign or message across during voice communications.  Use of standard phonetics will help you work DX countries or help get your emergency communications through accurately.  The table below shows the standard international phonetics recognized worldwide.
 

A	Alfa	N	November
B	Bravo	O	Oscar
C	Charlie	P	Papa
D	Delta	Q	Quebec
E	Echo	R	Romeo
F	Foxtrot	S	Sierra
G	Golf	T	Tango
H	Hotel	U	Uniform
I	India	V	Victor
J	Juliet	W	Whisky
K	Kilo	X	Xray
L	Lima	Y	Yankee
M	Mike	Z	Zulu

Radio waves "refracted" (bent) by ionosphere back to Earth

LOCAL PROPAGATION OF RADIO WAVES

• Used for UHF and VHF Communications
• Direct Radio Waves
• Ground Reflected Waves

REPEATER--Radio station that receives and retransmits radio signals

Click on the spectrum map to zoom

For worldwide communication, radio waves (HF) are about 30 to 500 feet (10 to 160 meters) long.
For local communication, radio waves (UHF/VHF) are about 1 to 6 feet (30 cm to 2 meters) long.

MIXER--used to modulate (change) frequency of wave by adding a second frequency in receiver.  Changes radio frequency (RF) wave into Intermediate Frequency (IF) in transmitter.  Changes IF into RF wave.

HETERODYNE--the combining (mixing) of two radio frequencies

5.  Learn the safety precautions for working with radio gear, and particularly DC and RF grounding.

Electrical Safety.  Although RF, AC, and DC voltages in most amateur radio stations can pose a potentially grave threat to life, common sense and knowledge of safety practices will help to avoid accidents.  However, carelessness can lead to severe injury or death.

• The primary wiring for an amateur radio station should be controlled by one master switch.  Other members of the household should know how to turn off the primary power.
• All wiring carrying power for the station should be of proper size for the current carried and insulated for the voltage level involved.  Electrical power outlets should not be overloaded.
• Bare wire open-chassis construction and open connections are an invitation to accidents.
• Whenever possible, kill the power and unplug equipment before working on it.  Discharge capacitors with an insulated screwdriver.  Don't assume the bleeder resisters are 100% reliable.
• Avoid bodily contact with any grounded object when working on electronics to prevent your body from becoming the return path from a voltage source to ground.
• Use insulated tools for adjusting circuitry
• Never work alone.  Have someone else present.  He or she could kill the power if your are being electrocuted.
• Insure the chassis of radio equipment is hooked to a good electrical and RF GROUND.

Radio Frequency (RF) Energy Safety.  The human body can be a very effective ground when exposed to RF energy, either when it is flowing on a conductor or radiating from an antenna.  Body tissues subject to large amounts of RF may/will suffer heat damage (burns).  Therefore, RF requires some extra safety.

• Confine RF radiation (energy) to antenna radiating elements.  Provide a good station ground.

• Stand no closer than 10-15 feet of a radiating antenna.  This is particularly true of vertical monopoles.
• Don't operate RF power amplifiers, especially VHF/UHF, with the covers removed.  (The shorter the wavelength, the more likely the body is to absorb it.)
• With mobile rigs of 10 watts or more, don't power the antenna when someone is standing next to it.
• With handheld transceivers with RF output above several watts, maintain at least an inch or so between the forehead and antenna.
• Don't work on antennas that have RF power applied.

6.  BLOCK DIAGRAMS consist of simple rectangles and circles with names or other designations within or adjacent to them to show the general arrangement of apparatus to perform desired functions.  The direction of power or signal flow is often indicated by arrows near the connecting lines or arrowheads on the lines.

 

SCHEMATIC DIAGRAMS show all major components and their interconnections.

Click to zoom Circuit Symbols

Example:  If bands 1, 2, and 3 are colored yellow, violet, and orange, respectively, the resistor has a value of 47,000 or 47K ohms.
There may be a fourth band; it indicates the resistor's "tolerance", or how close the manufacturer will guarantee the resistance value.