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Radio Badge. Merit Badge University 2005 Alpha Phi Omega. What is radio? Difference between broadcast radio & hobby radio? What is two-way communication?. Radio is a way of sending information from one place to another
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Radio Badge Merit Badge University 2005 Alpha Phi Omega
What is radio? Difference between broadcast radio & hobby radio? What is two-way communication? Radio is a way of sending information from one place to another Broadcast radio is 1-way communication where you can only hear but cannot reply Hobby radio is CB radio Two-way communication is where you can send and receive messages Introduction to Radio
Call Signs • Allow radio operators to identify themselves • Assigned by the FCC and unique to each station & area • First letter indicates the country; the second will be another letter; then a number which tells where the station was licensed and the last letters are assigned at random • In Cape Girardeau, a sample call sign would be NJ0578 (N for United States and 0 for Missouri) • Page 42-43 in your book shows a map of call sign assignments
Phonetics • Used when stations are hard to hear because the signal is low or there is static • Operators use phonetics to make themselves heard • Each letter has a word assigned to it • My name would be “Echo Romeo India November” in phonetics • Spell your name in phonetics, refer to page 44
How Radio Waves Travel • Radio waves travel similar to how light from light bulbs travel. Does anyone have any idea how they travel locally and around the world?
Locally, if the antennas can see each other, there is a direct signal The AM radio band is an example of a direct signal Think of light bulbs in a room… When the antennas cannot see each other, the waves are transmitted by bouncing through the ionosphere in the sky. Stations traveling around the world are referred to as “DX” because they are further away Page 15 in your book shows an example, use that to draw your own Locally vs. Around the World
WWV and WWVH • WWV is in Colorado • WWVH is in Hawaii • What do they do? • They keep radio stations in check by assuring listeners they have proper propagation • Propagation is the ability of radio waves to travel from one place to another
Electromagnetic Spectrum • Radio communications occur between 100 kilohertz and 1,000 megahertz • Page 17 of your book has a sample diagram of the radio frequencies spectrum • Let’s learn more about the electromagnetic spectrum
Radio uses a metric prefix to show how many “0” you need to add Kilo (1,000) add 3 100 kilohertz is the same as 100,000 hertz Mega (million) add 6 100 megahertz is the same as 100,000,000 hertz Page 16 in your book has other prefixes we are not dealing with Low frequency 30-300 kilohertz Medium frequency 300-3000 kilohertz High frequency or shortwave 3-30 megahertz Very high frequency 30-300 megahertz Ultra high frequency 300-3000 megahertz Metric System & Ranges
Diagram • Use page 17 as a guide and draw the electromagnetic spectrum • Locate • Medium frequency • High frequency • Very high frequency • Ultra high frequency • Microwave portions • 8 radio services (AM, FM, CB, TV, Amateur, and Police)
Federal Communications Commission-1934 Formed after the Federal Radio Commission Purpose is to assign radio frequencies and license people and groups who transmit radio signals International Telecommunication Union Assigns radio bands to one or more radio service or type of user Also police the radio bands FCC & ITU
Carry Information via Radio • DJ talks into a microphone • Transmitter picks up the energy and combines it with the radio frequency • Amplifier makes signal more powerful • Signal sent to the antenna for transmission • Transmitting antenna sends signal to the receiving antenna • Transceiver combines the transmitter and receiver
Safety Precautions • 2 MOST IMPORTANT • Never touch grounded metal or wet floors when you are working on radio equipment; this could cause a dangerous shock • Always keep 1 hand in your pocket; then there is no possibility of getting a direct shock from touching a hot point. It stops electricity from traveling across your chest and causing a heart attack
Block vs. Schematic Diagram • Both drawings show how an electrical circuit works • Block diagram uses blocks to show the different parts • This is shown on page 13 of your merit badge book • Schematic diagram uses symbols to take the place of actual drawings of the electrical parts • Take time now to draw a block diagram, using the one on page 13 as a guide
Circuits • Open • There is no current flowing through the circuit • Closed • The current flows correctly through it’s path • Short • Current does not flow through it’s proper course; it tries to take another route and is often too high and burns up the wire
More on Schematic Diagrams • What the parts do • Fuse—Protects the unit from getting too hot • Acts like a circuit breaker • Antenna—transmits and receives radio signal • Batteries—gives the station and radio power • Resistor—slows down the current flowing through the circuit • Capacitor—blocks the direct current but allows the alternating current through a circuit • NPN/PNP—Common types of transistors • Transistors are like a water faucet; controls the flow of electrons through the circuit • Triode Tube • Variable Resistors and Capacitors—there value can change
Draw the Parts • Pages 20-29 have the parts shown on the side of the page
Amateur Radio is a gateway to the world for 1,000s of people Practice motto “Be Prepared” Simulated Emergency Tests Public Service Announcements for non-profit organizations Technician Class License 35 questions on radio rules, operating practices, and basic electricity Receive full amateur privileges including ability to transmit on repeaters on the popular 2-meter band Given by volunteer examiners over age 18 and not related Amateur Radio Option
Q Signals • 3 letter combinations starting with the letter “Q” • Meanings set by international agreement • Page 46-47 list the various Q signals • Good evening • Best regards young lady • Thanks, see you later • Try sending morse code with your left foot now • Decode page 48, if time
Morse Code • Dit Di-dah-dit Di-dit Dah-dit Di-dit Di-di-dit Di-di-di-dit Dit Di-dah-dit Dit • Anybody know what that means? • Refer to page 19 in your book • Morse code is a secret language produced by interrupting the continuous wave signal from a transmitter to form the dots and dashes • The short and loud sounds are formed when the switch opens or closes the electrical circuit
QSL Cards & Log Books • Radio operators like to send a QSL card to the other operator to confirm the conversation • The cards then go into a log book where operators keep notes about interesting things they talked about • On all cards • Your call sign & the other contact’s call sign • Time, date & frequency • Mode • Radio signal report
Emergency calls Voice “Mayday” “SOS” Morse Code SOS Di-di-dit Dah-dah-dah Di-di-dit Why the FCC has an amateur license Helped in times of emergency Increase number of electronics expert Improve goodwill with other countries Assist with emergency communications To experiment with radio & communications More on Amateur Radio
Transceivers & Repeaters • Handheld transceivers • Allow you to receive messages when you are by yourself • Home “base” stations • Radios set up on a desk or a table & an antenna feed line comes in through a window • Mobile/hand-held radios • HT or Handie Talkie • allow you to communicate with others when you’re driving, walking, hiking, etc. • Repeaters • Picks up the signal when you’re using your handheld radio and allows you to talk to someone from further away
Wrap-Up • We’ve gone through all requirements except radio station visit • Hope you all had fun and learned about radio