CONGRATULATIONS!YOU ARE NOW THE PROUD OWNER OF A FELTED ANTIQUE RADIO

SURPRISE

TURN THE PAGE!

SOME OF YOURFAVORITE THINGS USE

RADIO WAVES!

RADIOSMICROWAVESCELLPHONESBROADCAST TELEVISION

(JUST TO NAME A FEW)

AM FM

AM FMAMPLITUDE MODULATION::::::::::::::::::

1906 - INVENTED BY REGINALD FESSENDEN

AM WAVES FLUCTUATE BASED ON SPECIFIC SIGNAL STRENGH (AMPLITUDE); IF THE AMPLITUDE IS NOT STRONG ENOUGH WHEN IT REACHES A RECEIVER, YOU WILL HEAR STATIC.

THE RECEIVER DETECTS THE CHANGES IN THE CARRIER FREQUENCYʼS AMPLITUDE AND AMPLIFIES IT TO DRIVE A SPEAKER.

BECAUSE AM WAVES DEPEND ON SPECIFIC AMPLITUDES TO GET A SIGNAL, THEY ARE LESS RELIABLE AND CAN EASILY BE DISRUPTED BY OBSTACLES SUCH AS TALL BUILDINGS.

FREQUENCYMODULATION:::::::::::::::::::

1933 - INVENTED BY EDWIN ARMSTRONG

FM WAVES FLUCTUATE BASED ON ʻFREQUENCYʼ (HOW MANY TIMES PER SECOND THE WAVEʼS CURRENT CHANGES DIRECTION.) SINCE MOST ENVIRONMENTAL FACTORS THAT DISTORT RADIO WAVES ONLY AFFECT ITS AMPLITUDE AND NOT THE FREQUENCY, THIS ALSO MEANS THAT FM SIGNAL QUALITY DOESNʼT DEGRADE LINEARLY AS YOU GET FURTHER FROM THE TRANSMITTING STATION.

FMʼS MOST SUBSTANTIAL BENEFIT IS ITS ABILITY SEND OUT TWO CHANNELS OF INFORMATION AT THE SAME TIME; THIS ALLOWS THE STATION TO BROADCAST LEFT AND RIGHT AUDIO CHANNELS FOR FULL STEREO SOUND!

TURNIT

UP!

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55

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90

92 94 96 98 100 102

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TUNE IT IN

*RADIO STATIONS CURRENTLY REGISTERED IN THE UNITED STATES

THIRTEENTHOUSANDTHREEHUNDREDAND FIVE*

TRAVELING

SPEED

299,792,458METERS PER SECOND

RADIO WAVESTRAVELATTHESPEEDOF LIGHT

TI ME

THE MORE YOU

GROWTHE MORE YOU

LISTEN

HRS HRS HRS HRSMINS MINS MINS MINS

A RECENT STUDY SHOWED THAT CHILDREN AS YOUNG AS SIX LISTEN TO THE RADIO AN AVERAGE OF SEVEN HOURS A WEEK.

7 20 8 55 14 00 22 45

SIX-EIGH

TYEA

RS OLD

NIN

E-ELEVENYEA

RS OLD

TWELVE-SEVEN

TEENYEA

RS OLD

EIGH

TEEN O

R M

OR

EYEA

RS OLD

WIR

ELESSLYAN

TENN

AS DO IT

AFTER CATCHING RADIO WAVES IN

THE AIR, THE ANTENNA THEN

FILTERS THE ENERGY DOWN INTO

A CIRCUIT BOX WHICH CONVERTS

THE WAVES BACK INTO SOUND.

ANTENNAS USE ELECTRICITY TO MANIPULATE THE ELECTROMAGNETIC FIELD

B O U N C E

EARTH

MOON

MOONBOUNCE:

IN A DAY BEFORE COMMUNICATIONS SATELLITES,HIGH POWERED RADIO WAVES WERE TRANSMITTED FROM ANTENNAS POINTED AT THE MOON.

THE MOON ACTS AS A GIANT MIRROR, BOUNCING THE RADIO WAVES BACK TO EARTH TO BE RECEIVED BY LISTENERS.

THIS WAS THE FIRST METHOD OF LONG DISTANCE RADIO

COMMUNICATION WHERE THE EARTHʼS IONOSPHERE DID

NOT DEGRADE THE SIGNALS BEING SENT.

RADIOIS

HARMLESS.

THEY DO NOT CARRY ENOUGH ENERGY TO

CHANGE THE STRUCTURE OF ATOMS IN THE

HUMAN BODY

RADIO WAVES ARE NON-IONIZING:

ELECTROMAGNETICSPECTRUM

100km

10cm

10cm

1mm

1mm

700nm

700nm

400nm

400nm

10nm10nm

10-2nm

10-2nm

10-6nm

THE ELECTROMAGNETIC SPECTRUM IS USUALLY DIVIDED INTO SEVEN DIFFERENT FREQUENCIES OF ELECTROMAGNETIC RADIATION:

RADIO

MICROWAVE

INFRARED

VISIBLE

ULTRAVIOLETX-RAY

GAMMA RAY

UNDERWATERUNDERWATER

ITʼS COMPLICATED.

REMEMBER

RADIO