Radio

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== Help with these requirements ==
== Help with these requirements ==
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1.
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*[http://en.wikipedia.org/wiki/Category:Broadcasting Broadcasting]
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*[http://en.wikipedia.org/wiki/Amateur_radio Amateur radio]
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*[http://en.wikipedia.org/wiki/Commercial_broadcasting Broadcasting (commercial)]
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*[http://en.wikipedia.org/wiki/Public_broadcasting Broadcasting (public)]
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*[http://en.wikipedia.org/wiki/Call_sign Call Signs]
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2.
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*[http://en.wikipedia.org/wiki/Radio Radio (in General)]
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*[http://en.wikipedia.org/wiki/WWV_%28radio_station%29 WWV station]
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*[http://en.wikipedia.org/wiki/WWVH WWVH station]
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3.
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*[http://en.wikipedia.org/wiki/Radio#The_electromagnetic_spectrum Radio spectrum (LF, MF, VHF, UHF, microwave)]
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*[http://en.wikipedia.org/wiki/DXing DX]
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*[http://en.wikipedia.org/wiki/DX_communication DX (distance) communications]
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In general, amateur radio operators are a good source of information and are excited to share their hobby with others. You may want to consider contacting the ARRL (see "External links" section) to find a nearby amateur radio club.
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4. Explain how radio waves carry information. Include in your explanation: transceiver, transmitter, amplifier, and antenna.
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5. Learn the safety precautions for working with radio gear, particularly DC and RF grounding.
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'''1.'''
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6.
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*[http://en.wikipedia.org/wiki/Block_diagram Block Diagram]
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Radio in general, broadcast and amateur: Radio waves travel farther and faster than sound waves, so if you want to talk to someone far away, using a radio is better than yelling. Broadcast means one way, their radio only transmits, your radio only receives, you can hear what they say but can't answer back (for example, a station that plays music). Two way means that both people have both transmitters and receivers, so you can carry on a normal conversation (for example, amateur radio or CB). See the "External links" section for Wikipedia entries on Radio (in General), Amateur radio, Broadcasting, Broadcasting (commercial), and Broadcasting (public).
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*[http://en.wikipedia.org/wiki/Circuit_diagram Circuit digrams]
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*[http://en.wikipedia.org/wiki/Electronic_symbol Electronic symbols]
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Call signs: radio stations use call signs to identify themselves because radio waves can travel far and wide and there is no easy way to tell where the station is transmitting from. It is possible to listen from several different places using special directional antennas and use trigonometry to calculate where a radio station is transmitting from, but it is much easier to simply wait until they say their call sign and then look up the call sign. See the "External links" section for the Wikipedia entry on call signs for a broad overview, the FCC entry on call signs for the official rules for amateur radio, and the Miscellaneous entry on call signs for a map of the amateur radio call sign areas in the US.
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*[http://en.wikipedia.org/wiki/Electrical_components Electrical components]
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7.
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Phonetic alphabet: The phonetic alphabet is used to prevent confusion between letters like "b" and "d" that sound similar enough to be easily mixed up. When talking over a noisy, static-filled radio (or cellular telephone) link it is even more easy to get letters mixed up, so one "code word" is substituted for each letter. For example, if Alice is introducing herself to Bob she may say "My name is Alice, I spell alpha lima india charley echo." See the "External links" section for a list of the "code words" in the international phonetic alphabet.
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*[http://en.wikipedia.org/wiki/Shortwave_listening Short-wave Listening]
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*[http://en.wikipedia.org/wiki/International_broadcasting International Broadcasting (Short-wave Listening)]
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'''2.'''
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How radio waves travel: Some frequency waves travel only in a straight line (line of sight), which doesn't travel around the curve of the earth and are therefore short range. Some frequency waves hug the ground and can go around the earth's curve, but these tend to die out quickly and are therefore mostly short range (unless you have a monster transmitter like the navy uses to talk to submarines, but very few folks have a transmitter that powerful). Some frequency waves bounce off the sky and then bounce off the ground and then bounce off the sky and continue to bounce again and again and again, which means they can go a very long ways, sometimes going all the way around the world. The details of how radio waves travel can be complicated, see the "External links" section for information on radio propagation if you want the entire, long story.
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WWV and WWVH: WWV and WWVH can be used as beacons (the radio equivalent of lighthouses) because they are in well known geographical locations and transmit on well known frequencies and because they broadcast constantly. If you can hear them you will probably be able to hear stations that are close to them (close meaning both close in geographic location and close in frequency). WWV is in Boulder, Colorado. WWVH is in Hawaii. Both transmit on several frequencies. They transmit the official time of the US Government, meaning they are an excellent place to set your watch to.
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'''3.a., 3.b., & 3.c.'''
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See the "External links" section for the ARRL band plans and amateur frequency allocations, the NTIA frequency allocation chart, and the Wikipedia entry on radio spectrum.
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'''3.d.'''
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See the "External links" section for the Wikipedia entry on DX, the FCC, and the ITU.
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'''4.'''
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An electronic circuit called an "oscillator" generates a radio frequency signal (oscillate means to wiggle back and forth). This RF signal is mixed with the information the sending operator is trying to send (this is called "modulating" the signal). For example, when sending Morse Code, the radio operator's key simply turns the signal on and off. Hold down the key and the signal is sent on through. Let the key up and the signal is shut off and is not sent on through. To send a dot, the operator presses the key down for a short time, meaning a brief signal is sent. To send a dash, the operator presses the key a little longer, meaning a longer signal is sent. The operator looks up the sequence of dots and dashes for the letter of the alphabet they want to send. Oscillators produce weak signals. These weak signals are strengthened by sending them through an electronic circuit called an "amplifier" (amplify means to make larger). Often the oscillator, modulator, and amplifier are put inside the same box, which we call a "transmitter." The signal is sent to an antenna, which takes in the electrical signal (which needs wires to travel through) and sends it out as an electromagnetic (radio) signal that does not need wires to travel (thus the word "wireless"). The signal has now been transmitted and is waiting for someone to receive it. The signal runs into another antenna, which converts the electromagnetic (radio) signal into an electrical signal. Often by this time the signal is very weak again, so it is sent through another amplifier to strengthen it. This signal is unmixed to separate out the information put in by the operator who sent the message (this is called "demodulating"). This demodulated signal is sent on to the operator receiving the message. In the case of Morse Code, the demodulated signal is simply sent to a speaker --- the operator either hears something or they don't. Hearing means the sending operator had the key pressed down. Not hearing means the sending operator did not have the key pressed down. Hearing a short pulse is a dot. Hearing a longer pulse is a dash. Look up the pattern of dots and dashes to get the letter of the alphabet the sending operator was trying to send. (Voice, television, fax, and computer information are sent the same way, the only difference being that the modulator and demodulator circuits are a bit more complicated than the simple "on/off" switch of Morse Code.) The box holding the receiving side amplifier and demodulator is called a "receiver". Sometimes the transmitter and receiver are put in the same box, which we call a "transceiver" (TRANSmitter + reCEIVER).
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'''5.'''
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'''6.a.''' See the "External links" section for the Wikipedia entries on block diagrams and circuit diagrams.
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'''6.b.'''
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'''6.c.''' Short circuit means two points in the circuit that you don't want connected are connected (for example, if you solder a wire to the wrong place, if you drop a screwdriver across the terminals of a battery, or if a tree branch falls on a power line). Open circuit means that two places in the circuit that you want connected are not connected (for example if a wire breaks or if you forget to hook up the load). Closed circuit means that the connections are all where you want them to be, meaning the current has a path to flow where you want it to flow and do what you want it to do.
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'''6.d''' See the "External links" section for the Wikipedia entry on electronic symbols and electrical components.
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* A battery is like a water tower --- it holds electricity (water) and provides the voltage (water pressure) to make the electricity move. (Electricity in motion is called electric current).
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* Wires are like pipes --- they give the electric current (water) a path to flow in.
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* Switches are like faucets --- they turn the flow off and on.
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* Resistors are like rust in pipes --- they restrict the flow of current.
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* Capacitors are like the kitchen sink --- they store and release current (water).
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* Diodes are one-way valves --- current can flow one way but not the other.
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* Photodiodes (also known as Light Emitting Diodes, or LEDs) are diodes that give off light when current flows through them. Think of them as very small light bulbs.
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* Fuses are automatic safety shutoff valves that protect against dangerously high current by blowing (creating an open circuit) when too much current flows. The open circuit prevents any more current from flowing, effectively turning the circuit off.
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* Transistors and tubes are like water pumps --- the amplify (make stronger) the voltage and/or current.
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* Transformers are another kind of water pump --- the step up the voltage (water pressure). If the transformer is connected backwards it steps down the voltage.
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'''7.a.''' You may want to consider contacting a local amateur radio club (see the ARRL web site in the"External links" section) about joining them for Field Day, Jamboree On The Air (JOTA), or any of the many contests that happen throughout the year. These events are often well attended in the amateur radio community and are a good chance to make some "QSO" contacts. On Field Day, many clubs operate a GOTA (Get On the Air) station that is dedicated to helping people with no radio experience get on the air and make contacts (GOTA station contacts get the club extra points, so the club will be happy to see you).
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# On air activities:
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# Contact and log:
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# Q signals
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# Technician class license and exam:
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# Emergency calls (why amateur radio?):
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# Base station vs mobile vs portable vs repeater:
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'''7.c.''' See "External links" section for the Wikipedia entries on Short-wave Listening and International Broadcasting.
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== External links ==
== External links ==

Revision as of 21:59, March 3, 2008

Radio merit badge
Status: Elective
Created: 1923
Discontinued: no
BSA Advancement ID:
Requirements revision: 2002
Latest pamphlet revision: 2001

Contents

“ ”
[[Category:{{{field}}} merit badges]]

Merit badge requirements

1. 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 radio and amateur radio call signs and using phonetics.
2. 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. Do the following:
a. Draw a chart of the electromagnetic spectrum covering 100 kilohertz (kHz) to 1000 megahertz (MHz).
b. Label the LF, MF, VHF, UHF, and microwave portions of the spectrum on your diagram.
c. 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.
d. Discuss why some radio stations are called DX and others are called local. Explain who the FCC and ITU are.
4. Explain how radio waves carry information. Include in your explanation: transceiver, transmitter, amplifier, and antenna.
5. Learn the safety precautions for working with radio gear, particularly DC and RF grounding.
6. Do the following:
a. Explain the differences between a block diagram and a schematic diagram.
b. Draw a block diagram that includes a transceiver, amplifier, microphone, antenna, and feedline.
c. Explain the differences between an open circuit, a closed circuit, and a short circuit.
d. Draw eight schematic symbols. Explain what three of the represented parts do. Find three electrical components to match to three of these symbols.
7. Do ONE of the following: (a OR b OR c )
a. Amateur radio
1. Describe some of the activities that amateur radio operators can do on the air, once they have earned an amateur radio license.
2. 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.) Properly log the real or simulated ham radio contact and record the signal report.
3. Explain at least five Q signals or amateur radio terms you hear while listening.
4. Explain some of the Technician Class license requirements and privileges. Explain who gives amateur radio exams.
5. Explain how you would make an emergency call on voice or Morse code. Tell why the FCC has an amateur radio service.
6. Explain handheld transceivers versus home "base" stations. Explain about mobile amateur radios and amateur radio repeaters.
b. Broadcast radio
1. Prepare a program schedule for radio station "KBSA" of exactly one-half hour, including music, news, commercials, and proper station identification. Record your program on audio tape using proper techniques.
2. Listen to and properly log 15 broadcast stations; determine for five of these their transmitting power and general areas served.
3. Explain at least eight terms used in commercial broadcasting, such as segue, cut, and fade.
4. Discuss the educational and licensing requirements and career opportunities in broadcast radio.
c. Short-wave listening
1. Listen across several short-wave bands for two 4-hour periods, one in the early morning and the other in the early evening. Log the stations properly and locate them geographically on a globe.
2. For several major foreign stations (BBC in Great Britain or HCJB in Ecuador , for example), list several frequency bands used by each.
3. Compare your morning and evening logs, noting the frequencies on which your major foreign stations were loudest during each session. Explain the differences in signal strength from one period to the next.
4. Discuss the purpose of and careers in short-wave communications.
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 license are required to operate and maintain the equipment, and the purpose of the station.

Source: 2007 Boy Scout Requirements (33215)

Worksheets

Merit Badge Worksheets can help Scouts organize notes, listen actively, and document their work. Many worksheets also contain links to free, online video instruction.

Notes

Per the BSA: You should read the merit badge pamphlet on the subject. Merit badge pamplets are available at your local Scout Shop or online at ScoutStuff.org.

You may want to consider working on the Radio and Electronics merit badges together, as there is some overlap.

If you wish to take a step past the merit badge and dig deeper into radio, the amateur radio Technician license is a natural next step. See the "External links" section for the ARRL entry on getting a license.

Help with these requirements

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2.

3.

4. Explain how radio waves carry information. Include in your explanation: transceiver, transmitter, amplifier, and antenna. 5. Learn the safety precautions for working with radio gear, particularly DC and RF grounding. 6.

7.

External links

Dedicated Radio Merit Badge Websites

ARRL (Amateur Radio Relay League)

FCC (Federal Communications Commission)

NTIA (National Telecommunications and Information Administration)

ITU (International Telecommunication Union)

Wikipedia

Miscellaneous

Retrieved from "http://meritbadge.org/wiki/index.php/Radio"
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