274 lines
9.2 KiB
Plaintext
274 lines
9.2 KiB
Plaintext
#################################
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# The ZEDNNET Presents... #
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# #
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# The Idiot's Guide to Radio #
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# Technology and Frequing #
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# #
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#################################
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By The ZEDNNET Writer #1 with help from the Unknown Freq
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Frequing
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--------
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Frequing (rhymes with phreaking) is a general term applied to all radio
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criminals and unauthorized radio hobbyists. The original idea of frequing was
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that the airwaves belong to the people, not the people with the bent minds and
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political action committees who influence the FCC. The people should directly
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control the spectrum. But before this can occure, there must be a radio uprising
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(like a civil war). This last idea is called "Radio Anarchy" where the hobbyist
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can compete for spectrum with companies and the government, and only the
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strongest signal can rule. The sign of a Radio Anarchist is a broadcast-type
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radio antenna with the top falling off and bending to one side, with a lightning
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bolt comming down from the sky and touching the antenna where the top part is
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falling off.The Freq sign is a large "Q" (the symbol for frequency) superimposed
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on a sign wave (with a zero level line).
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Radio Wave Theory
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-----------------
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Radio waves are kinds of electromagnetic waves, which are related patterns of
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electric and magnetic force. They are generated by the oscillation of electric
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charges. Electromagnetic waves move at the speed of 186,282 miles per second
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(light is an EM waves) through space.
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The EM spectrum consists of bands of wavelengths...
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Kind FrequencyWavelength
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---- -------------------
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23 -14
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Gamma rays 10 10
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19 -10
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X rays 10 10
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16 -9
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Ultraviolet 10 10
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14 -6
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Light 10 10
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13 -5
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Infrared 10 10
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10
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Radio Waves 10 .001-10,000
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(frequencies in Hertz, length in meters)
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You'll see a closer look at the radio spectrum in a while. All EM
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waves have the properties of light. They can be refracted, reflected,
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and diffracted, though some are harder to do than others.
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Radio Spectrum
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--------------
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The radio spectrum extends from the very low frequencies (VLF) of a few
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kilohertz though the "short waves" of a few megahertz to a few tens of mega-
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hertz, the very high frequencies (VHF) and the Ultrahigh frequencies (UHF)
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extending up to several hundred megahertz, and the micro wave region beginning
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about 1 Gigahertz (GHz).
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FreqWhat be there
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-----------------
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54-160 KHzAM Broadcasting
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285-325 Marine RDF Band
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1.8-2.0 MHzLoran A
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3.5-3.7 80 meter ham band
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7-7.340 meter ham band
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14-14.3520 meter ham band
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21-21.4 15 meter ham band
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26.965-27.255Citizen's Band
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28-29.7 10 meter ham band
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50-546 meter ham band
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54-88TV chan. 2-6
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88.1-108FM Broadcasting
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108.1-135Air Traffic
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144-148 2 meter ham band
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152-158 Mobile Services
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and Marine Radio
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174-216 TV chan. 7-13
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454-460 Airphones
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470-890 TV chan. 14-83
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10.525 GHzPolice Radar
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Uses of radio waves:
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--------------------
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Broadcasting
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Public Safety (Police, etc.)
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Industry (calling cabs, aircraft)
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National Defense
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Private Communication (Hams,
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Cordless phones, mobile phones,
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Marine Radio, Airphones, walkie-
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talkies, etc.)
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Navigation (beacons, Loran, VORTAC)
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Remote Control (Cars, planes,
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satellites, missles)
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Data Transmission
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Wireless Bugs
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Medical Information from inside
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the body
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Microwave Ovens
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You can see from these uses that those who control the radio waves control
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everything. Radio equipment is often expensive (though often not as expensive
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as computers), and difficult to work with. But with some determination, you can
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rule the world! (* Solder Sucker's NoteQQuote: He who controls the AirWaves
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controls the Universe! *)
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Sending the Signal
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------------------
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In order to send a radio signal, an electrical impulse has to be made, often
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from a microphone.This wave oscillates at audio-frequency, so called because if
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a speaker vibrates at this frequency, you can hear it. A "carrier wave" is then
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created. It's frequency is the frequency around where you want to transmit at.
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In order for a carrier wave to transmit informetion, it must be changed slightly
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. Amplitude Modulation (AM) does this by making small changes in the amplitude
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of the wave. The electrical wave from the microphone can be the guide to making
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the amplitude changes, and thus the voice is carried over the air. Frequency
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Modulation changes the frequency of the carrier wave up and down a little
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according to the audio-frequency wave.
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Thus, a high-fidelity audio transmission takes up about 20-40 kHz of spectrum
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around the carrier frequency.Telegraphy or other on-off modulation of the
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carrier wave take up less spectrum, say 50-100 Hz.
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The modulated carrier wave is then fed into a length of metal called an
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antenna. Antennas work best if they are the length of the wave, or just a bit
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more. The wave moves down the antenna and oscillates electrons. This
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oscillation causes EM waves to be produced.
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Wave Propagation
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----------------
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The Earth has a natural layer of ionized gas called the ionosphere. It is
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ionized because every day it is bombarded by large amounts of ultraviolet light.
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Fortunately for us, there is a layer of ultraviolet absorbing gas called ozone
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that protects us from this really cruel light that causes skin cancer and
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destroys proteins, and almost everything else.
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Low Frequency radio waves tend to bounce off the ionosphere more.
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FreqDistance with bouncing
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--------------------------
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Day Night
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1.8 MHz 25 2000
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3.5 200 3000
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7 500 3000
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14 Anywhere
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21 1000 2600
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"Skipping" of radio waves bouncing up to the ionosphere, and back down to
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earth, and maybe bouncing up again increase during the day to a maximum at
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sunset, then they slowly die down to a minimum around dawn, although often it is
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good to have the ionosphere highly iononized some distance away from you so your
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skip will hit it.
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Above 200 MHz there is no skip. Below 1.8 MHz, instead of bouncing or
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absorbsion, the waves usually just pass through the ionosphere heading for deep
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space. However, on some occurances, a signal like the AM band can skip a few
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hundred miles (I've picked up a Wahsington DC AM station (WTOP) in Cape Cod,
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Mass).
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Radio Terms
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-----------
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AM: Amplitude modulation
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Audio-Frequency: Waves in the frequency range of sound.
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Broadcast: A one way transmission to a large civilian audience
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Call Letters: Identify a radio station
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Carrier Waves: "Carry" the AF of a transmission
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Channel: A specified slice of spectrum assigned to a station
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FM: Frequency Modulation
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Frequency: speed of vibration
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Ham:Amateur radio operator
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Hertz: Frequency measure= 1 cycle per second
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Kilohertz: 1,000 hertz.
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Line-Of-Sight: A direct line to the reciever, only way to transmit
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over 200 MHz with regularity
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Megahertz: 1 million hertz
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Sky Waves: Waves that go up to the sky
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Recieving
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---------
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In order to recieve a radio transmission, the incomming wave excites a current
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in the recieving antenna. This current vibrates at the rate of the wave (i.e.
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has the same frequency). The carrier wave is removed from the audio wave, and
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the audio-wave is applied to a speaker.
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Radio Regulation
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----------------
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The U.S.:
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The federal communications commission (fcc) regulates all radio communication
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in the U.S. The fcc assigns call letters and frequencies for everything. They
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also issue licenses.
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The fcc does not censor radio programs, but can take action against stations
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that break rules.
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The fcc monitors the airwaves through many monitoring stations in the U.S.
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The most famous, the Laurel, MD Monitoring Station (The Laur) monitors almost
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the entire spectrum day and night.
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Because the radio is so important to national security, you can be assured
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that if you screw around with military freq- uencies, they'll be on you
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instantly. It isn't easy to track down a radio station, but it isn't super hard
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either. If you stay on the air illegally long enoughm they will find you. And
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then you are screwed majorly.
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Great Britain:
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Most British radio stations are government owned. The British Broadcasting
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Company regulates and provides programming to these stations. The Independant
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Broadcasting Agency (IBA) regulates independant stations. A famous independant
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network is Thames Television (Benny Hill, etc.)
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Canada:
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The Canadian Broadcasting Corporation (CBC) operates most of the major radio
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and shortwave stations, and is government run. The Canadian Radio-Television
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Commission supervises both government and independant stations.
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\\ QQQQ \\
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.......Q....Q..\
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\ Q\ QQQ\
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\ Q \QQQ \
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QQQQQ
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Q
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RADIO ANARCHY NOW!!!!!
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(c.o. Resonant Frequency)
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-------
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-*****- PRODUCED AND DISTRIBUTED
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----*-- BY THE ZEDNNET PHILE
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---*--- GROUP
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--*----
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-*****- THANX TO the unknown freq,
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------- RESONANT FREQUENCY,
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INCORSIS DAETHR, AND
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IPSE DIXIT.
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\ \|\
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\ | \
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\ \
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\ |\ \
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\| \ \
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\ \ | \
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(ZAP!)> .\|---|\
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:\*:.|-\
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:\\: \-|\
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.\.. \-:
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:\\: \
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:\:: \
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:\\: .
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:\::
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:\\:
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--------:\::-----------------
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:\\:
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RADIO ANARCHY NOW!!
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Call The Works BBS - 1600+ Textfiles! - [914]/238-8195 - 300/1200 - Always Open
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