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