Amateur Radio And Innovation In Telecommunications Technology

BPSKAcronym for “Binary Phase Shift keying”, a method of transmitting information (bits)in which a change in state of the transmitted carrier signal represents a “1”, while nochange represents a “0”ByteA group of eight binary digits processed as a unit by a computer and usedespecially to represent an alphanumeric characterCable ModemA technology that provides high-speed Internet service to customers via the existingcable television network. A cable modem provides higher speed on the incomingconnection than on the outgoing. Since many customers share a single cabletelevision segment, performance can degrade significantly as the number ofsubscribers increasesCarrierAn electromagnetic wave or alternating current whose modulations are used assignals in radio, telephonic, or telegraphic transmissionCBSee “Citizen’s Band”CD22204EAn integrated circuit that converts DTMF tones to the equivalent binary numberCDPDAcronym for “Cellular Digital Packet Data”, a data transmission technologydeveloped for use on cellular phone frequencies. CDPD uses unused cellularchannels (in the 800- to 900-MHz range) to transmit data in packets. Thistechnology offers data transfer rates of up to 19.2 Kbps, quicker call set up, andbetter error correction than using modems on an analog cellular channelChannelsSpecific frequencies that are assigned to a particular radio service. Amateur radiodiffers from other telecommunication services in that amateurs are not assignedchannels, but rather ranges of frequencies (“bands”) in which they may operate.Amateur radio is unique in that the hobbyist may change frequency at willxiv

CircuitA configuration of electrically or electromagnetically connected components ordevicesCitizen’s Band or CBA radio-frequency band officially allocated for unlicensed private radiocommunicationsClass C NetworkA globally-recognized allocation of Internet addresses numbering up to 254separate computersCLOVERAn HF digital mode invented in 1993 by amateur Raymond Petit (Bixby andHorzepa 1999 #39). CLOVER incorporates error detection and correction andoffers exceptional performance in the face of variable propagation on the HFamateur bands (Ford 2001 #91). It has found application in commercial as well asamateur communications (Bixby and Horzepa 1999 #39)Computer-mediated CommunicationHuman communication in which a computer system plays an integral role inmediating or transmitting/receiving the information which is exchanged. Without thecomputer, the communication could not take placeConnectionless CommunicationCommunication between two individuals or amateur radio operators in which noformal protocol exists to set up or initialize the communication before it beginsCQGeneral call from an amateur radio station calling any other amateurCurrentA flow of electric charge. Movement of electrons across a particular pointCWAcronym for “Continuous Waves”, in the vernacular, amateur communication usingthe international Morse codexv

Cycles per SecondThe unit of frequency; one Hertz has a periodic interval of one secondData RateIn computer-mediated communication, the number of bits per second which aretransferred between the sender and the receiver. A higher data rate implies ahigher bandwidth connection between the usersDayton HamventionAn important amateur radio convention held annually in Dayton, Ohio. Newtechnologies are often introduced at this gathering, and presentation of researchpapers at the convention serves to extend the state of the artDBSAcronym for “Direct Broadcast Satellite”, a relatively new direct-to-home satellitebroadcasting service that includes television and music channelsDemodulationTo extract the intelligence from (a modulated signal)DigipeaterSee “Repeater”. A repeater station that receives and retransmits digital data, suchas packet radio transmissionsDigitalOf or relating to a device that can read, write, or store information that isrepresented in numerical formDigital Signal Processing or DSPComputer manipulation of analog signals (commonly sound or image) which havebeen converted to digital formxvi

DOSAcronym for “Disk Operating System”, an early operating system for the personalcomputer3DSPSee “Digital Signal Processing”DTMFAcronym for “Dual Tone Multi Frequency”. An internationally accepted standard thatuses particular combinations of audible tones to represent the numbers from zerothrough fifteen. Eight separate audible tones are combined two at a time torepresent sixteen distinct valuesDumb TerminalA terminal that has no internal microprocessor and thus no processing powerindependent of its host computerDXColloquialism for “distant communication”. Amateurs commonly will wish oneanother “good DX”. “DXing” is an activity within the hobby in which enthusiasts try towork as many foreign countries and distant regions as possible. The “DXCC”award (“DX Century Club”) is granted by the ARRL to amateurs who submit proof ofcontact with amateurs in one hundred countries around the globeDynamic routingA characteristic of the Internet protocol TCP/IP, whereby data packets aretransmitted from the sender to the receiver in the most expedient fashion. Differentpackets may take different routes, i.e. travel through different intermediatecomputers, en route to delivery. Standard amateur packet radio, using the AX.25protocol, does not incorporate dynamic routing, rather, the sender must explicitlystate the route from sender to receiver, and identify all of the intermediate stations.Should one of the intermediate stations be unavailable, the packet will be lost3 While “DOS” in popular culture will be forever linked with the IBM personal computer, many earliermini- and mainframe computers from IBM and other manufacturers had disk operating systems,which were invariably referred to as “DOS”.xvii

Electromagnetic SpectrumThe entire range of radio frequencies, from very low to extremely high. What weunderstand as “radio waves” form only a tiny percentage of the availableelectromagnetic spectrum. Electromagnetic signals such as radio waves travel atthe speed of light, or rather, at the same speed as light travels, because visible lightis simply another small slice of the electromagnetic spectrumEmailElectronic mail, transmitted by amateur radio or over the InternetEME or MoonbounceAcronym for “Earth-Moon-Earth”. Vernacular for amateur radio “moonbounce”communication. Amateurs communicate with one another through intentionalreflection of their signals off of the surface of the moon. This is a very specializedamateur radio activity, accessible only to the best-equipped stationsError Detection and CorrectionMathematical manipulations of transmitted digital data allow for detection andcorrection of errors in the data stream. Redundancy is added to the transmitteddata in a clever manner that allows bits received with the incorrect values to becorrected at the receiverFacsimile or FAXA system of transmitting and reproducing graphic matter (as printing or still pictures)by means of signals sent over telephone lines. Amateurs adopted facsimile for usevia radio in the 1930sFamily Radio Service or FRSAn unlicensed radio communications service legislated in Canada and the UnitedStates. FRS is a low power, channelized service which allows informal, noncommercial radio communication by the general public.Fast Scan TelevisionAn amateur communications mode which is equivalent to “regular” television formatin terms of its technical specifications. Television pictures and audio aretransmitted at the standard rate of approximately 30 frames per second. This highdata rate implies wide bandwidth (approximately 6 MHz), therefore amateur fastscan television operation is restricted to the larger amateur bands, those above 420MHzxviii

FirewallA computer or computer software that prevents unauthorized access to private data(as on a company's local area network or intranet) by outside computer users (as ofthe Internet)FirmwareComputer programs contained permanently in a hardware device (as a read-onlymemory)Forward Error Correction or FECA method employed in digital communications whereby errors in transmitted databits can be detected and corrected by the receiver, without the need for retransmission of the corrupt bits by the transmitter. This is achieved by clevermathematical coding of the transmitted data bits. FEC adds overhead to digitalcommunicationsFree Software or Open SourceA concept of software development and distribution where computer programs aredeveloped and shared at no charge to the user community. Typically the sourcecode (the “recipe”) is included with the software package so that anybody may alterit to suit his or her needs. Open source software packages typically try to restrict theuser from selling the program or any derivatives of itFreeBSDAn open source version of the UNIX operating system, widely used on the Internetand by several large corporations and governments around the worldFrequencyThe number of complete oscillations per second of energy (as sound orelectromagnetic radiation) in the form of wavesFrequency ModulationModulation of the frequency of the carrier wave in accordance with speech or asignalFrequency Shift KeyingA type of modulation where the frequency of a carrier wave is shifted higher andlower in frequency in direct correlation with the information which is to bexix

transmitted. At the receiver, the frequency of the carrier is tracked and used torecover (or “demodulate”) the original information from the radio signalFrequency-Division MultiplexingA method of sharing the electromagnetic spectrum in which each radio signal, orradio or television station, is assigned a specific frequency or channel on which tooperate. AM and FM radio are common examples of frequency divisionmultiplexing: each station remains at a unique and legally-assigned spot on the dialFRSSee “Family Radio Service”GHzGigahertz. A unit of frequency equal to one billion (109) hertz. Historically called a“Gigacycle”GPSGlobal Positioning System. A system of satellites, computers, and receivers that isable to determine the latitude and longitude of a receiver on Earth by calculating thetime difference for signals from different satellites to reach the receiverGUIGraphical User Interface. An interface for issuing commands to a computer utilizinga pointing device, such as a mouse, that manipulates and activates graphicalimages on a monitorHamA licensed amateur radio operatorHam ShackColloquialism. The location from which the amateur radio enthusiast operates herequipment.Hertzunit of frequency equal to one cycle per second -- abbreviation HzHome-Brewxx

An amateur colloquialism for homemade radio equipment: transmitters, receivers,antennas, and station accessories.Amateur radio was founded on anexperimentalist, tinkering tradition. Home-brew equipment is still encountered inamateur radio today, but has become less popular over the past quarter-century,due to relaxation of licensing requirements and the increased complexity and lowercost of commercial radio gearHybrid TechnologyA communications technology that combines, or exhibits aspects of, both analogand digital communicationsInternetAn electronic communications network that connects computer networks andorganizational computer facilities around the worldInteroperabilityAbility of a system to use the parts or equipment of another systemIntranetA network operating like the World Wide Web but having access restricted to alimited group of authorized users (as employees of a company)IonizationTo convert wholly or partly into ionsIonosphereThe part of the earth's atmosphere in which ionization of atmospheric gases affectsthe propagation of radio waves, which extends from about 30 miles (50 kilometers)to the exosphere, which is divided into regions of one or more layers whosealtitudes and degrees of ionization vary with time of day, season, and solar cycle,and which is contiguous with the upper portion of the mesosphere and thethermosphere; also : a comparable region of charged particles surrounding anothercelestial body (as Venus)IP AddressAn address that uniquely identifies a node on a computer network. “IP” stands for“Internet Protocol”xxi

ITUAcronym representing “International Telecommunication Union”KSymbol from electronics representing the number 1000. 56K represents thenumber 56,000. In computer science the term K represents 1024 rather than 1000,as 1024 is a power of two (210) and is therefore easily represented in binarynotationKeyboard-based CommunicationDigital amateur communications employing the keyboard rather than themicrophone or other device for interaction between the parties. Examples areradioteletype (RTTY) or packet radioKeyboardingVernacular for the activity of typing back and forth, using keyboard-basedcommunication, between two or more amateur stationsLANAcronym for “Local Area Network”. A system that links together electronic officeequipment, such as computers and word processors, and forms a network within anoffice or buildingLEO SatelliteAn orbital satellite that circles within a few hundred kilometres of the earth’s surface.Distinct from geostationary satellites, which orbit about 35,000 km above the earth,or Molniya satellites, which orbit in an elliptical fashion, varying in height between afew hundred and several thousand kilometres above the surface of the earthLinuxA trademark for an open-source version of the UNIX operating system.Mail ServerA repository, typically a computer system, that stores electronic mail for users, whoare required to login to retrieve their messages. Typical forms in amateur radioinclude BBSes and packet radio mailboxes. Advanced projects such as the 56Kpacket network employ UNIX-based mail servers that run software and protocolsequivalent to those used on the Internetxxii

MboneVirtual Internet Backbone for Multicast IP. IP Multicast-based routing allowsdistributed applications to achieve real-time communication over IP wide areanetworks through a lightweight, highly threaded model of communicationMeteor ScatterA specialized mode of amateur communication where the ionized trails of meteorsthat enter the Earth’s atmosphere are used to propagate (reflect) radio signalsMFAcronym for “Medium Frequency”. Typically used to refer to the amateur bands upto and including 4.0 MHz in the e

A main support or major sustaining factor, in terms of communications networks, the conduit over which most communications or data packets must travel Bands Segments of the electromagnetic spectrum allocated to amateur radio. Bands are colloquially identified by their approximate wavelength, for example the amateur