GENERAL ACRONYMS FOR EMS COMMUNICATIONS BPS—bits per second. BSC—binary synchronous communications

A C AA—above average terrain C—Celsius AC—alternating current CAD—computer –aided Dispatch ACD—automatic call distributor CB—citizens band ACLS—advanced cardiac life support CCH—computerized criminal history ACSB—amplitude compandored single- CCITT—International Telegraph And Telephone Consultative Committee ADP—automatic data processing CCSA—common control switching AGL—above ground level arrangement ALS—advanced life support CCTV—closed circuit television ALERT—automatic law enforcement CCU—Coronary Care Unit or Critical Care response team Unit ALI—automatic location identification CDC—Cooperative Dispatch Center AM—amplitude CG—Channel Guard(R) Trademark of AMSL—above mean sea level General Electric ANI—automatic number identification CMED—Central Medical Emergency APB—all points bulletin Dispatch APCO—Associated Public-Safety CMR—Common Mode Rejection Communications Officers CMRR—Common Mode Rejection ASCII—American Standard Code for CNIL—Calling Number Identification and Information Interchange Location ASTM—American Society for Testing and CO—Central Office Materials. COG—Council of Governments ASTRA—Automated Statewide COR—Coronary Observation Radio And Records Access CPR—cardiopulmonary resuscitation ATLS—Advanced Trauma Life Support CJIS—Criminal Justice Information System AT&T—American Telephone and CTCSS—Continuous Tone Controlled Telegraph Company Squelch System AVC—automatic volume control AVI—automatic vehicle identifications D dB—decibel B dBm—decibel reference to 1 mW. balun—balanced-to-unbalanced line dBu—decibel referenced to 1 mV/m transformer dBv—decibel referenced to 1 V BCD—binary coded decimal dBW—decibel referenced to 1 W BFO—beat frequency oscillator DC—direct current BIT—binary digit DCS—Division of Computer Services BLS—basic life support DDD—direct distance dialing DID—direct inward dialing dod—direct outward dialing DOD —US Department of Defense DOT—US Department of Transportation FCC—US Federal Communications DRG—diagnosis related grouping Commission DP—double pole FCCA—Forestry Conservation DPDT—double pole double throw Communications Association DTMF—dual-tone multi-frequency FEMA—Federal Emergency Management DPST—double pole single throw Agency FET—field-effect transistor E FM— EACOM—emergency and administrative Freq.—frequency communications system FORTRAN —formula translation EAS—extended area service (computer language) E & M-–the receive and transmit leads of a FSK—frequency-shift keying signaling system FX—foreign exchange EAX—electronic automatic exchange ECC—emergency communications center G EDP—electronic data processing GE—General Electric EIA—Electronic Industries Association GESS—General Electric Service Station EMD—emergency medical dispatcher GFW—ground fault warning EMF—electromotive force GHZ—gigahertz (1000 MHz) EKG—electrocardiogram GIGO—garbage in, garbage out EMDPRS—emergency medical dispatch GMT—Greenwich Mean Time (Zulu) priority reference system GSA—General Services Administration EMS—emergency medical service GT&E—General Telephone and EMSS—emergency medical service system Electronics EMT—emergency medical technician EMT-B—emergency medical technician- H basic HEAT—hospital emergency administrative EMT-D—emergency medical technician- radio defibrillator HF—high frequency EMT-I—emergency medical technician- HYSIS—highway safety information intermediate system EMT-P—emergency medical technician- HV—high voltage paramedic Hz—hertz EOC—emergency operations center EOM—end of message I ERCC—emergency resource coordination I—current in amperes center IAFC—International Association of Fire ERP—effective radiated power Chiefs ESS—electronic switching system IACP—International Association of Chiefs EST—Eastern Standard Time of Police ETA—Estimated Time of Arrival IC—integrated circuit ETV—Educational Television ICO—individual channel oscillator ICOM—integrated circuit oscillator module F ICU—intensive care unit F—Fahrenheit ICX—intercity exchange link IEEE—Institute of Electrical and Electronic Engineers M IF—intermediate frequency MAST—Military Assistance to Safety and IMSA—International Municipal Signal Traffic Association MCCU—mobile coronary care unit IMTS—improved MF—medium frequency IRAC—Interdepartmental Radio Advisory MHz—Megahertz Committee MICT—Mobile Intensive Care Technician ISPERN—Illinois State Police Emergency MICU —Mobile Intensive Care Unit MRCC—Medical Resource Coordination IT&T—International Telephone and Center Telegraph Corporation ITU—International N Union NABER—National Association of Business and E Radio, Inc. J NCIC—National Crime Information Center JAN—Joint Army-Navy Specifications NCMCN —North Carolina Medical JETEC—Joint Electron Tube Engineering Communications Network Council NEAR—national emergency aid radio JFET—junction field-effect transistor NHTSA—National Highway Traffic Safety UPS—uninterruptible power supply Administration USIT—US Independent Telephone NLETS—national law enforcement Association telecommunications system USFS—US Forest Service NPA—Number Plan Area Journal of Emergency Medical Services O K O-D—origin-destination UPS—uninterruptible power supply ONI—operator number identification USIT—US Independent Telephone OTP—Office of Telecommunications Association Policy USFS—US Forest Service kbps—kilobits per second P kHz—kilohertz (1000hertz) UPS—uninterruptible power supply USIT—US Independent Telephone L Association LATA—local access transport area USFS—US Forest Service LMR—land LEAA—Law Enforcement Assistance PABX—Private Automatic Branch Administration Exchange LETS—Law Enforcement Teletypewriter PBX—Private Branch Exchange Service PL—Private Line(r) Trademark of Motorola LORAN—long range navigation PM—Pulse Modulation LSI—large scale integration PSAP—public safety answering point LOS—line of sight PSCC—Public Safety Communications LRO—lead regional organization Council LSU—life support unit PTT—Press to Transmit or Push to Talk VSWR—voltage standing wave ratio Q VTVM—vacuum tube voltmeter QEI—quantifiable evaluation indicator VU—Volume Unit

R W RCU—remote control unit WATS—Wide Area Telephone Service RF— WECO—Western Electric Company Rx—receive WPM—words per minute

S X SERS-Special Emergency Radio Service Xcvr.—transceiver SIRSA—Special Industrial Radio Service Xfmr.—transformer Association Xmit.—transmit SMR— Xmtr—transmitter SMSA—standard metropolitan statistical Xtal—crystal area SPA—State Planning Agency Z SWR—Standing Wave Radio Z—impedance ZULU —time zone at Greenwich, England T TASI—time assignment speech interpolation TCAM—telecommunications access method TLOF – Touchdown Liftoff Area Telco—telephone company TPL—terminal per line TPS—terminal per station Tx—transmit

U UHF—ultra high frequency UL—Underwriters Laboratories, Inc. UPS—uninterruptible power supply USIT—US Independent Telephone Association USFS—US Forest Service

V V—volts VAC—volts, alternating current VDC—volts, direct current VHF—very high frequency VOM—volt-ohm meter VOR—voice operated relay VOX—voice operated switch FCC CODES AND NAMES OF RADIO SERVICES industrial: IB—business Classes of Radio Stations (FCC): IF—forest products FB—base IM—motion picture FB2—mobile relay IP—petroleum FB4—community repeater IS—special industrial FX1—control IT—telephone maintenance MO—mobile IW—power MO3—mobile/vehicular repeater IX—manufacturers FXO—operational fixed IY—relay press FX2—fixed relay FX—fixed FLT—auxiliary test Motor Carrier: FXY—interzone LI—interurban passenger FXZ—zone LJ—interurban property LR—radio location LU—interurban passenger MR—radio location mobile LV—urban property 806-821/851-866 MHz Bands:

Land Transportation: Conventional Category Trunked LA—automobile emergency GB business YB LR—railroad GO industrial/land transportation YO LX—taxicab GP public safety/special emergency YP GX commercial (SMRS) YX

Public Safety: 292-930 MHz Band: PF—fire GS—private carrier paging systems PH—highway maintenance PL—local government PP—police PO—forestry conservation PS—special emergency RS—radio location ZA—general mobile

GLOSSARY analog—Physical representation of information such that the representation A bears an exact relationship to the original information. Pertaining to data in the form acoustic feedback—The transfer of sound of continuously variable physical qualities waves from a loud speaker or end terminal to any previous component within an audio analog communication—System of system. telecommunications used to transmit information other than voice which activity—The expenditure of time and is sometimes used in telemetry. resources. —A system of wires or electrical adapter—A device used for changing the conductors employed for reception or terminal connections of a circuit or part to transmission of radio waves. Specifically, a connect to another circuit or part with unlike radiator that couples the or connections. lead-in to space for transmission or receptions of electromagnetic radio waves. It alphabet, phonetic—A method of passing changes electrical currents into alphabetic information substitution over a electromagnetic radio waves and vice versa. poor communication path with word substitution for letters. One phonetic antenna, isotropic—A theoretical antenna alphabet is: Alfa, Bravo, Charlie, Delta, with identical radiation in every direction. Echo, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, antenna, parabolic—A directional antenna Quebec, Romeo, Sierra, Tango Uniform, with a radiating(or receiving) element, and a Victor, Whiskey, X-ray, Yankee, Zulu. parabolic reflector that concentrates the power in a beam. American Standard Code for Information Interchange (ASCII)—An eight-level code antenna polarization—The direction of the for data transfer adopted by the American radiated electrical field in relation to the Standards Association to achieve surface of the earth. Generally vertical in compatibility between data devices. mobile radio use.

amplitude compandored single- arc—A discharge of electricity. sideband—A form of sideband modulation used for narrow channel transmission that arrester, lightning—A device designed to incorporates a pilot tone. protect electrical equipment or property from damage by lightening. (AM)—Modulation in which the amplitude of the carrier- assigned frequency—The frequency frequency current is varied above and below appearing on a station authorization from its normal value in accordance with the which the carrier frequency may deviate by audio, picture, or other intelligence signal to an amount not to exceed that permitted by be transmitted. the frequency tolerance.

Associated Public-Safety automatic volume control (AVC)—A self- Communications Officers (APCO)—A acting gain control which maintains the non-profit public safety radio users group output of a receiver constant despite composed of administrators and variations in received signal strength. communications technical, operations, and command personnel. automatic number identification (ANI)— Equipment for recording the calling party’s ASTM—A scientific and technical number without operator intervention. organization formed for the development of standards on characteristics and performance B of materials, products, systems, and services. back bone—A point-to-point communications system utilizing several attack time—The interval required after a stations. sudden increase in input signal to a transducer (transmitter, receiver, etc.) to back-to-back repeater—A repeater attain a percentage of final output level due consisting of a receiver and transmitter with to this increase. the output of the receiver connected directly to the input of the transmitter. attenuation—The decrease in amplitude of a signal during its transmission from one band (radio frequency)—A range of point to another. It may be expressed as a frequencies between two definite limits. By ratio or, by extension of the term, in international agreement, the radio spectrum decibels. is divided into nine bands. For example, the very high frequency (VHF) band attenuator—A device for reducing the extends from 30 MHz to 300 MHz. energy of a wave without introducing distortion. Also called a pad, gain control, bandpass filter—Passes frequencies within level adjustor, volume control, etc. a specified band, and attenuates all frequencies outside that band. audible signal—A buzzer, bell, or other audible sound device that indicates an bandwith—(1) The width of a band of incoming call. frequencies used for a particular purpose, (2) the range of frequencies within which a audio—Pertaining to frequencies performance characteristic of a device is corresponding to normally audible sound above specified limits. For filters, waves. These frequencies range from 15 to attenuators, and amplifiers these limits are 20,000 Hz. generally taken to be 3 dB (half-power) below the average level. aural—Pertaining to the ear or sound. baseband—For microwave systems, the automatic gain control (AGC)—A receiver available frequency band that the RF circuit that maintains the output constant equipment is capable of transmitting. with wide variations in the in the receiver input level. —An item of fixed radio bit—A unit of digital information hardware consisting of a transmitter and (abbreviation of “binary digit”). receiver. boom microphone—A microphone baud—Used to define the operating speed arranged on an arm type mechanical support of a printing telegraph of data system. It is to permit better placement of the the total number of discrete conditions or microphone. signal events per second. braid—A group of fibrous or metal baudot code—A five-unit code used for filaments or threads woven into a cylindrical teletypewriter signals. shape to form a covering over one or more wires. —A radio transmitter or lights designed to indicate exact geographical broadcast—Radio or television location or direction. transmission intended for general reception. beam—A configuration of radiated energy Business Radio Service—A subpart of the whose rays are sharply directional and Industrial Radio Services section of the FCC parallel. rules. beat—A regularly recurring pulsation from busy indicator—An indicator provided at a the combination of two-tone or frequency control point to indicate the in-use condition waves of different frequencies. of a circuit or channel. beat frequency—the frequency produced C when signals of two different frequencies are combined and refracted. The beat cable—One or more insulated or frequency is equal in value to the difference noninsulated wires used to conduct electrical between the original frequencies. current or impulses. Grouped insulated wires are called a multi-conductor cable. bel—A unit of relative power, named after , and used to express calibrate—To determine error by differences in power. comparison with a known standard. beeper—a pocket paging receiver that emits call, all—The alerting of all decoder a beeping sound upon receiving a page equipped units in a system by the specifically directed to it. transmission of a single coded signal. biomedical telemetry (biotelemetry)—The call, group—The alerting of subdivided technique of monitoring or measuring vital selective call groups by function, type of biological parameters and transmitting data vehicle, location, etc. by sending a single to a receiving point at a remote location. coded signal.

Biophone—Trade name of Biocom, Inc. for call, individual—The alerting of a specific portable telemetry devices. coded decoder unit by sending a single coded signal. carrier control timer (CCT)—A device call answer—The initial answer of a call for that limits the length of time that the assistance whether by 9-1-1 or other transmitter carrier is on. telephone method. carrier frequency—The frequency of an —Federal Communications unmodulated electromagnetic wave Commission assigned identifying letters and produced by the transmitter. numbers used for identification of a radio station, transmitter, or transmission. cavity resonator—A space enclosed by a metal conductor in which oscillating call referral method—The calling party is electromagnetic energy is stored and whose referred to a secondary number resonant frequency is determined by the geometry of the enclosure. call relay method—The call is answered at the PSAP where the pertinent information is cellular radio—A commercially available gathered and then the interrogator relays the mobile or portable radio telephone service. information to the proper public safety agency for their action. This can be Celsius—The metric scale of temperature in accomplished by radio, intercom, telephone, which water freezes at zero degrees and etc. boils at 100°C. To convert a Celsius temperature to Fahrenheit, multiply by 9/5 call transfer method—The PSAP and add 32. interrogator determines the proper responding agency and connects the user central medical emergency to that agency which then performs the dispatch(CMED)—See command and necessary dispatching in accordance with control center. prearranged plans with cooperating agencies. central office—Sometimes called a wire center; the smallest subdivision within the call party hold—Enables the public safety telephone system which has relatively answering point to control the connection permanent geographic boundaries. for confirmation and tracing of a call. change out—To replace. capture effect—An effect occurring in FM reception when the stronger of two signals channel element—A temperature on the same frequency suppresses the compensated crystal oscillator weaker signal. channel guard—General Electric’s cardioid microphone—A microphone trademark for continuous tone coded having a heart-shaped space response squelch system (CTCSS). pattern of 180° in front, and minimum response in the rear. channel, point-to-point—A radio channel used for radio communications between two carrier—A radio signal generally without definite fixed stations. voice or other information.

channel, radio—An assigned band of radio used for rating, identification, and frequencies of sufficient width to permit its assignment purposes. use for radio communication. The necessary width of a channel depends on the type of —A transmission line in which transmission and the tolerance for the one conductor completely surrounds the frequency of emission. other, the two being coaxial and separated by a continuos solid dielectric or by channel, television—A band of radio dielectric spacers. frequencies 6 MHz wide used for television broadcast code dialing—A method of signaling or encoding and decoding address codes by the channelization—The assignment of circuits use of standard telephone dial. to channels, and the arrangement of those channels into groups. command and control center (central communications center)—A system which charge—To replenish the electrical is responsible for establishing potential in a battery or capacitor. communications channels and identifying the necessary equipment and facilities to charge, fast or quick—A method of permit immediate management and control quickly recharging batteries under controlled of an EMS patient. This operation must conditions. provide access and availability to public safety resources essential to the effective charge, trickle—The continuous charge of and efficient EMS management of the a battery at a slow rate. immediate EMS problem.

chart, 4/3 earth’s radius—A radio profile common mode rejection (CMR)—The chart whose horizontal lines are curved to ability of differential amplifier to reject correspond to an earth having a radius 4/3 unwanted signals. times larger than actual earth radius. communications subsystem—Comprises chassis—The framework on which parts of those resources and arrangements for a radio or other electronic circuits are notifying the EMS system of an emergency, mounted. for mobilizing and dispatching resources, for exchanging information, for remote circuit merit—A rating of overall circuit monitoring of vital indicators, and for the quality. Circuit merit ‘5” is clear circuit. radio transmission of treatment procedures Merit ‘3’ is readable with noise. Any rating and directions. below ‘3’ is not readable and generally unacceptable. communications system—a collection of individual communication networks, class of service—Service order code transmission system, relay stations, control designation of the combination of telephone and base stations, capable of interconnection service features (equipment, calling area and inter-operations that are designed to units, dial types) to which business and form an integral whole. The individual residence customers subscribe. It is components must serve a common purpose, be technically compatible, employ common procedures, respond to control and operate control console—A desk-mounted, in unison. enclosed piece of equipment which contains a number of controls or circuits used to comparator—A circuit which compares operate a radio station. tow or more signals, and selects the strongest or best. control head—A device with appropriate controls, microphone, volume, squelch, compression—In audio systems, reducing on/off, etc., generally mounted in a vehicle, the volume range of the input signal so that from which control of the radio or mobile the minimum output has less noise, and the unit is performed. maximum output has less distortion. control point—A position from which a compressor—A variable gain audio device radio system is controlled and supervised. used to provide a relatively constant output level for a wide range of varying input control, remote—A control scheme for a levels. radio system where all control functions are performed remotely via telephone lines. cone of silence—The area directly over or under a vertical transmitting antenna in continuous duty—(1) An unending which little or no signal is radiated. transmission (2) Operating 100% of the time (3) EIA—full load output under the console—A cabinet housing electronic manufacturers normal loading conditions for circuitry normally used in controlling other the class of service for 24 hours. equipment such s transmitters and receivers installed at a remote location. control, local—A control system packaged with the control unit mounted directly on the consolette—(1) Motorola Communications base station. name for a desk top radio station (2) A device for mounting a mobile microphone, coordination, frequency—The cooperative control head and speaker. selection and allocation of radio frequencies such that all systems can operate with continuous tone controlled squelch system minimum interference. (CTCSS)—A system wherein (s) are equipped with a tone couple—To connect two circuits so that responsive device which allows audio signals are transferred from one to the other. signals to appear at the receiver audio output only when a carrier modulated with a coverage—In a radio communications specific tone is received. The tone must be system, the geographic area where reliable continuously present for continuous audio communications exist; usually expressed in output. CTCSS functions are sometimes terms of miles extending radially from a referred to by various trade names such fixed radio station. as private line or PL(Motorola Communications & Electronics), Channel crosstalk—The unwanted transfer of energy Guard or CG(General Electric Mobile from one communication circuit to another Radio) or Quiet Channel (RCA). by means of a mutual coupling. crystal—A piece of quartz or similar transmitted through a communications material that has been ground thin and to the system. proper size to produce vibrations at the desired frequency. Used in radio dedicated telephone line—A telephone transmission to generate, with a high degree wire pair, originating at one point, and of accuracy, the assigned carrier frequency terminating at another point, operating in a of a station. closed circuit. Also called private line. cut over—To transfer from one system to defibrillator—An electrical device used to another. eliminate fibrillation of the heart muscle, by the application of high voltage impulses. cycle—One complete reversal of an alternating current, including a rise to the demodulation—The process of recovering maximum level in one direction and a return the modulating information from a to zero. The number of cycles occurring in modulated signal. one second is the frequency of the current. The word cycle is commonly used to deviation ratio—The ratio of the maximum mean cycles per second (hertz). frequency deviation of the RF carrier to the highest frequency contained in the D modulating band. dBm—Decibels referenced to one milliwatt. dial tone first—Allowance of a 9-1-1 or ‘0’ Employed in communication work as a operator calls to be completed without the measure of absolute power. Zero dBm deposit of a coin in a telephone pay station. equals one milliwatt. digital—Data represented in discrete, dBV—Decibels referenced to 1 V. discontinuous form, as contrasted with analog data represented in continuous form. dBW—Decibels relative to 1 W (1 dBw = 30 dBm). digital dial code—A signaling technique generally used in VHF radio systems to decibel (dB)—A unit which expresses the bypass a receiver CTCSS system level of power value relative to a reference power value. Specifically, the level of diplexer—A device which enables the use power, value P, relative to a reference value, of two radio transmitters, operating on PR, in decibels is defined as dB = different frequencies, on the same antenna 10*log10(P/PR). simultaneously.

DC control—A remote base station control direct—In terms of communications scheme that requires metallic conductors circuits, means a dedicated instant method and currents of communications. A dial telephone is not direct, a radio or a ring down line are direct. decoding—The conversion and recognition by the addressed (receiving) unit of direct dispatch method—A system where numerical address codes that have been all 9-1-1 call answering and radio dispatching is performed by the personnel at effects of by combining several the public safety answering point. signals all bearing the same information.

direct distance dialing(DDD)—Telephone doctor-interrupt—The ability of a service which permits subscribers to dial physician or hospital-based communicator to their own long distance calls. interrupt the voice or telemetry transmission from a radio in the field. direct leased land lines—Dedicated or designated point-to-point wire circuits dual-tone multi-frequency (DTMF)—The telephone) used in transmitting voice or data simultaneous generation of two audio tones communications. See dedicated telephone generally compatible to AT&T’s standard line. “touch-tone” frequencies. Used for control or signaling purposes. A method of direct trunking—An arrangement where a sending specific pairs of audio tones for telephone line connection has no each digit, up to a total of 16. intermediate points before reaching the final destination (called) party. duplex—The operation of transmitting and receiving apparatus at one location in directional antenna—An antenna which conjunction with associated transmitting and radiates radio waves more effectively in receiving apparatus at another location: the some directions than in others. process of transmission and reception being simultaneous. The simultaneous directivity—The value of the direction gain transmission and reception of information. A of an antenna in the direction of its duplexed piece of equipment is capable of maximum value. transmitting and receiving simultaneously. Duplex systems generally employ different dish—A type of antenna. A parabolic transmitting and receiving frequencies. reflector used in microwave systems. duplexed operation—The operation of dispatch point—A position from which a associated transmitting and receiving radio system is used but not a supervision or apparatus concurrently as in ordinary control point. Dispatch points are not telephones without manual switching usually listed on a station radio license. between talking and listening periods. For comparison see simplex operation. distortion—Unfaithful reproduction of audio or video signals due to change duplexed/multiplexed telemetry unit—A occurring in the wave form of the original radio device capable of simultaneous signal, somewhere in the course of its transmission and reception and concurrent transmission or reception. The lower the transmission of both voice and EKG percentage information. of distortion, the more distortion free the system is and the more intelligible the duplexer—A device which is used in radio message. equipment to provide simultaneous transmit and receive capabilities on a single antenna. diversity—A method of radio transmission, or reception, or both, which counteracts the duplex, half—A system in which times the antenna height in feet aboveground communication may be in either direction level. but only one way at a time. Transmission in one direction at a time over a single channel. EKG display console—A unit of electronic equipment located in a hospital emergency E room, or cardiac care unit, or both, which displays EKG and records voice and data E & M signaling—An arrangement by information received from an EMS scene by which signaling between two points on a transmission via radio or telephone path. radio or carrier path is accomplished. An M A demodulation display console. lead is associated with the transmit (or mouth) while the E lead is associated electrocardiogram(ECG or EKG)—A with the receiver (or ear). visual or hard copy trace of a patient’s electrical heartbeat information. EACOM—Emergency and Administrative Communications for hospitals. Trade name electrode—(1) Either of the two terminals for VHF radio system operating on standard of an electric source, such as a battery, (2) A frequencies with a system conducting element through which electric between stations. The system is similar to current enters or leaves an electrolyte, gas, Motorola Communications HEAR radio or vacuum, (3) A conducting element, system. usually metallic (such as silver/silver chloride), with a conducting medium or effective height—The true electrical height electrolyte (such as sodium chloride and of an antenna corresponding to a “perfect” water) attached to a patient to obtain the antenna that will produce the same field electrical signals of the heart. strength. The height of its center of radiation above the effective ground level. electromagnetic radiation—Radiation associated with a periodical varying electric effective radiated power(ERP)—The and magnetic field and is traveling at the calculated power output from an antenna speed o flight, including radio waves, light system which incorporates all the gains and waves, X-rays, and gamma radiation. losses in the antenna system. ERP is calculated as follows (1) convert power electromagnetic wave—A wave of output of transmitter to dB referenced to 1 electromagnetic radiation, characterized by W(dBw); (2) subtract all transmission line variations of electric and magnetic fields. losses including losses in equipment between the transmitter and antenna emergency call—A all that requires (filter, diplexers, circulators, duplexers, etc.) immediate action. expressed in dB; (3) add the antenna’s power gain (expressed in dB reference to a emergency medical dispatcher (EMD)—a half-wave dimple); and (4) convert the trained public safety telecommunicator with results into watts. additional training and specific emergency medical knowledge essential for the efficient effective signal radiated—The rating basis management of emergency medical for licensing radio transmitters. Equal to the communications. square root of the effective radiated power emergency medical dispatching—The encoding—The conversion of numerical reception and management of requests for address codes, such as telephone number or emergency medical assistance. message codes, into a format of tone or on- off pulses of audio tones for transmission emergency medical dispatch priority over a communications system, usually reference system (EMDPRS)—A for individual or group addressing, such as medically approved reference system used for paging or selective calling. by a local dispatch agency to dispatch aid to medical emergencies, which includes: exchange—A defined area, served by one or systematized caller interrogation questions, more telephone central offices, within which systematized pre-arrival instructions, and the telephone company furnishes service. protocols matching the dispatcher'’ evaluation of injury or illness severity with exciter—The low level stages of a vehicle response mode and configuration transmitter which normally consists of an oscillator, modulator and multiplier. Emergency Medical Service (EMS)—The service utilized in responding to the extender board—A printed circuit board perceived individual need for immediate that plugs into a module’s circuit connector medical care in order to prevent loss of at one end and the module on the other to life or aggravation of physiological or maintain a circuit so that the module may be psychological illness or injury. conveniently tested out of an inaccessible position. emergency operations center (EOC)—(1) A secure, protected facility designed and F equipped for the use of community officials to manage response of a community in time facility—A communications facility is of emergency, (2) A communications center anything used or available for use in the designed and operated by a community or furnishing of communications service. within a geographic area for a combination of emergency resources, such as police, fire facsimile—The process by which pictures, and EMS. images, and other fixed graphic materials are scanned and the information converted emergency resource coordination center into electrical signals for local use or (ERCC)— Generally a facility that has the transmission remotely to produce a likeness resources and ability to coordinate all of the subject copy. emergency services (police, fire, EMS, etc.) within a given geographic area. ERCC fading—The variation of radio field works in conjunction with a public safety strength caused by a gradual change in the answering point (PSAP) and may be in the transmission medium. same facility or location. —The number of decibels of enclosure—A housing such as a case, attenuation which can be added to a cabinet, cabinet rack or console which is specified radio frequency propagation path designed to provide protection and support before the signal-to-noise ratio of the to equipment. channel falls below a specified minimum.

FCC Part 90—The section of the Federal F-Layers—The upper layers of ionization in Communications Commissions Rules and the ionosphere. The f-1 layer is about 130 Regulations that affects most EMS miles above the earth. The f-2 layer height communications. varies from about 250 miles during the day to about 150 miles at night. Federal Communications Commission (FCC)—A Board of commissioners float—To operate a storage battery in appointed by the President under the parallel with a charger and a load at such Communications Act of 1934 to formulate voltage that the charger supplies the load Rules and Regulations and to authorize use current and the battery supplies only of radio communications. The FCC transient peaks above the normal load. regulates all communications in the United States by radio or wireline, including FM transmitter—A radio transmitter that television, telephone, radio facsimile and emits or radiates a frequency modulated cable systems. wave. feedback—The act of returning a portion of folded dipole—A receiving or transmitting the output voltage of a circuit which antenna composed of two parallel dimples, includes amplification to the input of that connected at the ends. The connection to the circuit. receiver or transmitter is made at the center of one of the poles. feedback, acoustic—The feeding back of sound waves from a loudspeaker to a forced disconnect—The capability of the 9- microphone in the same audio system. 1-1 center to disconnect a 9-1-1 call to avoid caller jamming of the incoming phone lines. field strength—The strength of an electric, magnetic or electromagnetic field. four wire operation—Telephone operation Electromagnetic (radio) field strength is in which the inbound audio signal is carried expressed in microvolts per metre or on one pair of wires and the outbound signal millivolts per metre. on another pair. fixed service—A service or radio free space loss—The theoretical radiation communication between specified fixed loss that would occur in transmission if all points. Fixed station: (1) a radio station variable factors were disregarded. Free which is not mobile; (2) a station which space loss depends only on the frequency is permanently installed; (3) a base station in and the distance between antennas. a mobile radio system. frequency—The number of cycles, fixed relay station—An operational fixed repetitions, or oscillations of a periodic station established from the automatic process completed during a unit of time. The retransmission of radio communications frequency of waves in the electromagnetic received from either one or more fixed spectrum (radio waves) is designated in stations or from a combination of fixed hertz (Hz), kilohertz (kHz = 1000 Hz). One and mobile stations and directed to a hertz is equivalent to one cycle per second. specified location. frequency modulation (FM)—A method of compared against a standard (usually an modulating a carrier-frequency signal by isotopic antenna). The radio of standard causing the frequency to vary above and antenna power to the directional antenna below the unmodulated value in accordance power that will produce the same field with the intelligence signal to be strength in the desired direction. transmitted. The amount of deviation in frequency above and below the resting generator, standby power—A device frequency is at each instant proportional to which develops electrical voltage from the amplitude of the intelligence signal mechanical energy. An a-c electrical power being transmitted. The number of complete source held in reserve and used to supply the deviations per second above and below the necessary a-c power when commercial resting frequency corresponds at each power fails. instant to the frequency of the intelligence signal being transmitted. generator, signal—A portable test oscillator which can be adjusted to provide a frequency response—The transmission loss test signal at some desired frequency, or gain of a system, measured over the voltage, modulation, or waveform. useful bandwidths, compared to the loss or gain at some reference frequency (generally geographical assignment—The assignment 1000 Hz). and use of communications channels on a dedicated used basis within a given fresnel zone—The circular zone about the geographic area. direct path between a transmitter and a receive at such a radius that the distance GHz—Gigahertz (billion hertz, 1000 MHz) from a point on this circle to the receiving point has a path length that is gin pole—A pole which is used together some multiple of a half wave length longer with ropes and pulleys as a derrick for lifting than the direct path. heavy loads and for erecting poles or towers. fringe area—An area or locality at such a ground—A reference point. Also a distance from the transmitter that the signals connection, intentional or accidental, received are weak. between an electrical circuit and the earth or its equivalent. full-duplex operation—A method of operation of a radio system which provides ground plan antenna—A type of vertical simultaneous two-way communications transmitting or receiving antenna used between two points. In EMS radio primarily for short wavelength or high band systems, provides for mutual interrupt communications. A ground plane antenna capabilities between the field technician and consists of a quarter-wave vertical element, the physician or medical direction at a and four radial elements spaced 90° apart, hospital location. and mounted on the base of the vertical element. Antennas of this type are non- G directional and have a low angle of radiation. gain, of an antenna—The effectiveness of a directional antenna in a particular direction, ground wire—A conductor leading from commercial operators. A person that makes the radio equipment to an electrical operation a hobby. connection with the ground. harmful interference—Any emission, guard band—A narrow band of frequencies radiation, or induction which endangers the provided between adjacent channels in functioning of a radio service or seriously certain portions of the radio spectrum to degrades,obstructs, or repeatedly interrupts a prevent interference between stations. radio communication service. guy anchor—The buried weight or mass to hand microphone—A microphone which the lower end of a guy wire is designed to be held in the hand. Sometimes attached. called a “palm” microphone.

H handset—A device similar to a telephone handset used in place of a hand microphone. half-duplex channel—A communication channel providing duplex operation at one hardcopy—A tangible printed copy of a end of the channel, but not the other. message such as that obtained from a Sometimes, the base station is operated in typewriter. the duplex mode, however, in EMS the portable or mobile radio is often operated hardware—The screws, nuts, clamps, in the duplex mode, and the base station at anchors, connectors, etc. used in the the hospital operated simplex, to permit the installation and maintenance of medical direction physician to interrupt communications systems. transmissions from the field technician. See also Simplex. hardwire—To wire or cable directly between units of equipment without passing half-duplex operation—Generally refers to through other media. the ability of directing medical personnel in EMS radio system to interrupt or ‘break in’ harmonic—An integral multiple of a on radio transmissions from field personnel fundamental frequency. The third harmonic to give instructions or ask questions. of 20 Hz is 60 Hz. The fifth harmonic of 40 Sometimes referred to as “physician Hz is 200 Hz. interrupt”. Requires duplexed communications equipment in the field. hash—Noise signal produced by an electrical or mechanical source. half-wave dipole antenna—A straight, ungrounded antenna having an electrical headphone—A device which can be placed length equal to half the wave length of the on the head to allow individual listening to signal being transmitted or received. messages. Mounted vertically, it has a donut-shaped pattern, circular in the horizontal plane. HEAR—Hospital Emergency Administrative Radio— Motorola ham—A term applied to an amateur radio Communications and Electronics trade name operator, as opposed to business or for a VHF radio system operating on standard frequencies with a selective calling hot line—Direct circuit between two or system between stations. The system is more points for immediate use without similar to General Electric Mobile Radio patching or switching. (See direct leased Department’s EACOM radio system. land lines) The hot line can employ various signaling configurations (ringdown, audio helix—A single layer, spiral wound coil amplifier, etc.) usually having air or foamed polyethylene core. hot standby operation—A method of achieving reliable operation by energizing hetrodyne—(1) pertaining to the production two identical equipments fed by and to a of difference in frequencies (beat switchable input and output. A sensing frequencies) by the combination device causes transfer of input and output of the two frequencies, (2) to shift an circuits when a failure is indicated. incoming radio signal to a different frequency, often to a lower intermediate hum—Audio frequency interference which frequency. is at the frequency of the power supply or its harmonics. Hetrodyne frequency—The beat frequency, which is the sum or difference humidity, relative—The ratio of the between two frequency signals. amount of water vapor the air contains to the maximum amount it could hold at the same hertz(Hz)—International unit of frequency temperature and pressure, expressed in identical to and used instead of the old term percent. cycles. One hertz is equal to one cycle per second. hybrid—(1) Made up of several different components or a mixture of technologies. high band—A portion of the VHF radio (2) A circuit required to convert 4-wire frequency spectrum from 150 to 174 MHz in operation to 2 wire, while maintaining which two-way radio operates. isolation of the 4-wire circuit. hollerith code—A twelve-level code which I defines the relation between an alphanumeric character and the punched ignition noise—Interference produced by holes in an 80-column data card. sparks or other ignition discharged in a vehicle. hookswitch—The device on which a handset or microphone hangs when not in image—One of the two groups of use. The handset operates a switch, or generated in the process of , so switches, which open the associated circuits. called because one is the reverse (mirror image) of the other with respect to operating hop—(1) The number of reflections from frequency. the ionosphere encountered by the in traveling from the transmitter to the image frequency—In hetrodyne frequency receiver (2) the number of radio links converters, an undesired input frequency required to span a given path. which can beat with the local oscillator to

produce the intermediate frequency and thus in-band signaling—The transmission of appear in the receiver output. signaling tones within the frequency band of the channel. image rejection—The action of a receiver in suppressing the image frequency. insertion loss—The loss introduced when a device or line section is interposed between impedance—The total resistance that a two elements of a circuit. circuit offers to the flow of alternating current. Impedance is a combination of insulation—Any nonconductive material resistance and reactance. The ohm is used as used to prevent the leakage of electricity a unit of impedance measurement. from a conductor, such as rubber, glass, mica, etc. impedance match—The condition in which the impedance of one component is the same integrated circuit—A complete circuit as the component to which it is connected or consisting of transistors, capacitors, attached. resistors, diodes, etc. which is formed on a single substrate. impedance, characteristic—The importance of characteristic impedance lies Integrated Circuit Oscillator Module in the fact that when a transmission line is (ICOM)—A frequency determining circuit terminated, as with an antenna, in an used in General Electric containing a impedance matching its own, then all of the crystal oscillator circuit and other circuits energy or power flowing along the line is used to generate the oscillator frequency. radiated by the antenna. If the impedance of the termination (antenna) is not matched to interface—A concept involving the the transmission line, a portion of the energy specification of the interconnection between will be reflected at the mismatch resulting in two equipments or systems. The a lower output from the antenna. specification includes the type, quantity, and function of the interconnection circuits and Improved Mobile Telephone Service the type and form of the signals to be (IMTS)—A mobile radio telephone offering interchanged via these circuits. of a telephone company. interference—Interference in a signal impulse—A surge of electricity having a transmission path is either extraneous power single polarity. which tends to interfere with the reception of the desired signals or the distribution of indicator—A device used to inform of a signals which results in loss of signal or condition or change in condition. distortion of information. induced—Produced as a result of exposure intermittent—Not continuously present; to a changing electric or magnetic field. disappearing and reappearing.

Industrial Radio Service—An FCC- intermittent duty cycle—A duty cycle of 1 designated radio service. minute on 4 minutes off, or 20% per electronic industries association (EIA). intermodulation—The combination of two energy with the object of impairing the use signals beating together to form a third of electronic devices, equipment or systems. unusable signal which interferes with the reception of the desired signal. In a radio jumper—A short length of conductor used receiver the method of expressing in dB to bridge electrical connections. below the desired signal, the receiver’s rejection of the unwanted signal to its junction box—A metal or other container acceptance of correct signals. into which wires or cables are led and connected. intrinsically safe—A laboratory (UL) rating for equipment considered approved to K operate in areas in which hazardous concentrations of flammable gases exist. key—A push-to-operate switch used for operating a transmitting circuit in a radio inverter—(1) Any of several devices used system to convert direct current to alternating current (2) a single input, single output key telephone equipment—An instrument device which changes the polarity of that has the capability of multiple line (inverts) a signal when passing it from input terminations. Each line is accessed by to output. A negative signal at the input depressing an association button (key). produces a positive signal at the output and vice versa. A differential EKG amplifier has keypunch—A machine controlled by a a normal and an inverting input. typewriter like keyboard which enables an operator to punch holes in predescribed ionosphere—The upper portion of the places in a hollerith code. earth’s atmosphere beginning at about 50 miles above the surface of the earth’ the kilo—A prefix meaning one thousand. cause of radio signals being bent, and returned to earth. kbps—Thousands of bits per second. kilohertz(kHz)—Equal to 1000 cycles per isolator—A passive RF device which second. Replaces the term kilocycle. permits transmission in only one direction, absorbing energy in the opposite direction. klystron—An electron tube in which the electrons are periodically bunched by J electric fields. Used as an RF oscillator for microwave equipment. jack—A connecting device ordinarily used to make electrical contact with mating knockout—A metal disc punched in the contacts of a plug. side of a metal terminal junction box or cabinet which can be punched out to allow jacket—The outer covering on an insulated entry of a cable or conduit. wire or cable. L jamming—The deliberate radiation, re- radiation or reflection of electromagnetic land line—A generic term which refers to the public-switched telephone system. to the signal input voltage. A straight line lag—The difference in phase angle relationship. expressed in electrical degrees between the voltage and current which produced it. line, balanced—A two-wire line which has identical impedance from each wire. land-mobile—An abbreviation for land to mobile communications such as between line equalizer—A connection in series with base stations and mobile radios or from a telephone line that will alter the frequency mobile radio to mobile radio. response characteristics of the line.

Land Mobile Radio Service—A mobile line, four-wire—A two-way transmission radio service defined by the Federal circuit using separate paths for transmit and Communications Commission-FCC Rules receive functions. and Regulations Part 90. line, loss—A transmission line, usually a LATA—Local access and transport area coaxial cable, which is designed to have boundaries for telephone companies. The very high transmission loss per unit length geographic area within which the local used in tunnels, underground or buildings telephone company provides local and long for radio communications systems. distance service. line of sight—An unobstructed path Law Enforcement Assistance between two points. Radio waves at those Administration (LEAA)—An frequencies where signals travel in a straight administration under the United States line and are not reflected by the ionosphere. Department of Justice established by the Omnibus Crime Control and Safe Streets line of sight distance—The straight-line Act of 1968, restructured by the Justice distance from a radio station antenna to Improvement Act of 1979 and abolished two horizon. This represents the normal years later. transmitting range of FM transmitting stations. leased line—A pair of wires or a circuit, usually leased or rented from a telephone link—The portion of a radio relay system company, designed for exclusive use between adjacent radio stations. between two fixed points for various communication control functions. load—(1) A device that receives power from a transmission system (2)The amount life cycle—A test performed on a material of electric power drawn by an electric or device to determine the length of time electronic device. before failure. load, dummy—A device which can line—A transmission lien or power line. A dissipate energy (into heat) without radiating system of one or more wires. it.

linear—Describing a device in which the loading, antenna—Insertion of reactance in signal output voltage is directly proportional an antenna circuit to improve its transmission characteristic in a given loss—A decrease in power suffered by a frequency band. signal as it is transmitted from one point to another, usually expressed in decibels. loading, ice—The stress imposed on an Energy dissipated without accomplishing antenna or antenna structure caused by ice useful work. forming on its members. loss, free space—The theoretical loading, wind—The stress imposed on an transmission loss between two radio antenna or antenna structure caused by antennas dependent only upon distance and wind. frequency. lobe—One of the three-dimensional petals loss, path—The theoretical transmission representing the radiation or reception loss between two efficiency of a directional antenna. radio antennas dependent only upon distance and frequency. local government radio service—A service of radio communication defined by the FCC loss, path—The reduction or attenuation of essential to official activities of states, signal strength that occurs between the possessions, and territories, including transmitted strength and the received signal counties, towns, cities, and similar strength. governmental subdivisions. low band—A section of the VHF radio local service area—That area that can be frequency spectrum from 25 to 50 MHz in called on the telephone without incurring which mobile radio equipment is licensed to multimessage units or a toll charge. operate. log—A list of radio stations showing low loss—Describing circuits and frequency, location, power, and other data. transmission line in which little energy is Also a communication record for a station lost from the input to the output. showing calls made, time, date and other data. A detailed record. lower sideband—The lower of two frequencies or of two groups of frequencies loop—(1) A short transmission line that produced by a modulation process. connects a subscriber to a switchboard (2) A closed path in which a signal may circulate. lug, spade—A connector which has an open This path may be within a piece of end to slip under a terminating screw. equipment, such as a repeater or carrier terminal, or may be a complete carrier M circuit. marginal—Operating at the borderline of loop resistance—The resistance presented permissible limits. to the signaling portion of the terminating set by the wireline when the far end of the matrix—An array of horizontal and vertical wireline is short circuited. input or output leads with cross points at the intersections, used as a means of switching from any input to any output. mobile station—A two-way radio station in mean—The arithmetic middle point of a the mobile service intended to be used while range of values, obtained by adding the in motion or during halts at unspecified highest and lowest values and dividing by points. two. mobile telephone service (MTS)— median—The point below which there are Telephone service between a fixed mobile as many instances as there are above. radio base station and several vehicles equipped with mobile radios. medical communications control console—An installation of communications mobile transmitter—A radio transmitter control equipment, usually located at a designed for installation in a vehicle, vessel, hospital, which provides for control of the or aircraft and normally operated while in transmitting and receiving equipment motion. necessary for the medical communications. mobile unit—A two-way radio equipped microwave—A term applied to radio waves vehicle or person. Also sometimes the two- in the frequency range of 1,000 MHz and way radio itself, when associated with a upward. Microwave radio generally vehicle or person. performs the same functions as telephone cables, and may be used for radio remote modem—Contraction of modulator- control purposes. demodulator.

mobile—Term used to describe equipment modular—A construction technique designed for vehicular installation. incorporating the use of standard size units for interchangeability. mobile relay station—A fixed station established for the automatic re-transmission modulate—To vary the amplitude (AM), of mobile service radio communications frequency (FM), which originate on the transmitting or phase of a high frequency wave or carrier frequency of the mobile stations and which in step with amplitude variations of another are retransmitted on the receiving frequency wave (the modulating wave). The carrier is of the mobile stations. usually a sine wave while the modulating wave is often a complex voice or EKG mobile repeater station—A mobile station signal. in the mobile service authorized to retransmit automatically on a mobile service modulator—The electronic circuit that frequency communications originated by combines the modulating wave with the handheld or portable units or by other carrier wave. In radio transmitters the final mobile or base stations directed to such audio-frequency stage which mates the hand-carried units. audio signal with the carrier signal. In EKG telemetry, the circuit that combines the mobile service—A service of radio amplified EKG signal with the subcarrier communications between mobile and land (audio) signal for transmission by radio or stations, or between mobile stations. telephone. multi-channel system—A radio system which uses more than one radio channel. mute—To silence or reduce sound level. Also known as a multifrequency system. N multicoupler, receiver—A device which permits several radio receivers to use the netting—The process of adjusting a same antenna. Usually a broadband system’s transmitters and receivers to the amplifier with several output ports. same operating frequencies. multi-frequency operation—Employing net loss—The algebraic sum of the gains radio equipment capable of operation on two and losses between two terminals of a or more frequencies. circuit. multijurisdictional system—A system network—An orderly arrangement of covering more than one political boundary stations interconnected through or agency. communications channels in order to form a coordinated entity. multipath—The propagation phenomenon which results in signals reaching a radio nine-one-one(9-1-1)—A three-digit receiving antenna by two or more paths emergency telephone number accepted and usually resulting in a degradation of promulgated by the telephone industry as the the original signal. nationwide emergency number. multiplex—Transmitting two or more Nxx—The first three digits of a local signals over the same medium. In EKG telephone number that uniquely identifies telemetry equipment, the ability to transmit that central office switching location within electrocardiograph(EKG) signals and voice its area code number for nationwide long signals concurrently over the same distance call routing. transmitter. noise—Interference characterized by multiplex, frequency division—A undesirable random voltages cause by an multiplex system in which the total internal circuit defect or from some external transmission is divided into source. Any extraneous signal tending to narrower bands each used for a single interfere with the proper and easy perception separate channel. of those signals which are intended to be received. multiplex, time division—A method of in which the total frequency noise blanker—A device used in mobile spectrum available is used by each channel, radio applications which senses the presence but only for part of the time. A sharing of of undesired noise on the desired channel transmission ability, first by one parameter, and causes the desired signal to be then by another. interrupted for the time period that the undesired noise signal is present. The time multi-tone—A method of signaling that period is controlled and measured in involves tow or more tone signals produced milliseconds so that the interruption of the simultaneously or sequentially. desired signal is not audible. P noise level—Volume of noise usually expressed in decibels. paging—A one-way communications service from a base station to mobile or noise —A circuit that cuts off the fixed receivers that provide signaling or noise peaks that are stronger than the highest information transfer by such means as peak of the desired signal being received. tone, tone-voice, tactile, optical readout, etc. nomograph—A chart having three or more pair—Two wires of a signal circuit scales across which a straightedge can be generally applied to telephone wherein one placed to provide a graphical solution for a wire is designated “tip” and the second wire particular problem. In mobile radio, “ring”. nomographs may be used to determine frequency spread, estimated radio range, passive—A device which does not antenna height, etc. contribute energy to the signal it passes.

O passive repeater—A device intentionally interposed in a microwave transmission path octave—The interval between two to redirect or reflect energy. frequencies having a ratio of two to one. patch—A means of connecting one system ohm—An electrical unit of resistance. to another. A patch may be between radio systems, or radio to telephone, as in a ohm’s law—The current in an electric radio/phone patch. circuit is directly proportional to the electromotive force in the circuit. In the path, signal—The route by which form E=I*R, where E is the electromotive intelligence is conveyed from transmitter to force (voltage), I is the current (amperage), receiver or through a circuit. and R is the resistance of the circuit (ohms). personal radio—A small portable radio omnidirectional—Equally effective in all intended to be carried by hand or on the directions. person of the user. open—A break in circuit continuity PERT—Program Evaluation and Review Technique. A management tool for outage—A disruption of communications comparing actual with scheduled program from any cause, whether planned or progress. accidental. phase—The position at any instant which out-of-band signaling—Transmission of the periodic wave occupies in its cycle of signals by frequencies outside of the voice 360° band. phone patch—An interconnection between overload—A load greater than a device is radio and telephone communications circuits designed to handle. which permits direct voice interchange between telephone lines and radio system. public safety telecommunicator—An pigtail—A splice made by twisting together individual trained to communicate by the bared ends of two conductors. electronic means with persons seeking emergency assistance and with agencies and plug-in—Describing any device having individuals providing such assistance. terminals so it can be connected by simply pushing it into a suitable socket or pull box—A box with a removable cover connector. installed in a conduit run to facilitate pulling wire or cable into the conduit. portable—An easily transportable radio. pulse—A signal of short duration. primary power—A reliable source of electrical power normally serving as the pulsed tone—A system of selective principle source of energy to equipment, signaling using a keyed on-off tone signal. such as the commercial 120 volt a-c power main. push-to-talk or press-to-talk(PTT)—In radio or telephone systems, that method of private automatic branch exchange- communication over a speech circuit in (PBX)—A telephone switchboard with which transmission occurs from only one many stations not individually identifiable to station at a time, the talker being required the telephone company’s switching network to keep a switch operated while he is requiring an operator. talking. The keying button used to operate a transmitter. private line(PL)—Motorola’s trademarked name for continuous tone controlled squelch Q system, CTCSS. quarter-wave antenna—An antenna propagation, electromagnetic—The travel electrically equal to one-fourth of the of electromagnetic waves through a wavelength of the signal to be transmitted or medium, or the travel of a sudden electric receive. disturbance along a transmission line. Also called wave propagation. quartz—An element consisting of pure silicon dioxide. The original piezoelectric protect—To equip with devices for material widely used to control the safeguarding from damage by excessive frequency of oscillators. voltages, current, or physical abuse. quartz crystal—A thin square or public safety agency—A functional rectangular slice of quartz which will vibrate division of a public agency which provides at a frequency determined by its thickness. fire fighting, police, ambulance, emergency medical, or other emergency services. quiet channel—The RCA Corporation’s trademarked name for continuous tone public safety answering point (PSAP)— controlled squelch system (CTCSS). The initial answering location of a 9-1-1 call and other calls for assistance. quieting—Reduction of system noise.

quick-call—Motorola communications each other by sharing the same radio Company trademarked name for a system of channel or channels. selective calling, normally using two pairs of two tones each in sequence. Quick Call II radio common carrier (RCC) —An uses a pair of sequential tones similar to enterprise that is licensed by the FCC and General Electric’s Type 99 tone system. the Public Utilities Commission to provide radio communications service to the public. R radio receiver—An instrument which rack mounting—A method of mounting amplifies radio frequency signals, separates equipment in which metal panels supporting the intelligence signals from the rf carrier, the equipment are attached to pre-drilled amplifies the intelligence signal steel channel rails or racks. The dimensions additionally, and converts the intelligence of the panels, the spacing of the rails and the signal to its original form. size of the mounting screws are standardized. radio relay system (radio relay) —A point-to-point radio transmission system in rack unit—In mobile radio generally a rack which the signals are received and mounting 19 in. between rails and a height retransmitted by one or more intermediate of 1.75 in. per unit. radio stations.

radio—The transmission and reception of radio transmitter—A radio-frequency signals by means of electromagnetic waves power source which generates radio waves without a connecting wire. for transmission through space.

radio-frequency power—The power radome—A dome shaped cover for a associated with any signal consisting of parabolic antenna which protects the electromagnetic radiation which is used for antenna from the elements and their telecommunications. attenuating effects.

radio interference—Undesired disturbance range—Distance over which a radio signal of radio reception. Man-made interference is can be transmitted for effective reception or generated by electric devices, with the the distance at which a usable signal can be resulting interference signals either being received. radiated through space as electromagnetic waves or traveling over power lines or other receiver—An electronic device used to conducting media. Radio interference is also detect and amplify transmitted radio signals. due to natural sources such as atmospheric phenomena, such as lightning. Radio receiver, paging—A small, light, pocket transmitters themselves may additionally sized receiver used for alerting individuals interfere with each other. when they are away from their normal communication instruments. radio network—A number of radio stations, fixed and mobile, in a given referral methods—The calling party to a geographical area which are jointly public safety answering point is referred to a administered or which communicate with secondary telephone number. communication signals and delivering refraction—The change of direction corresponding signals which are either experienced by a wave of any form of amplified or reshaped or both. radiated energy when passing from one medium to another having a different repeater station—An operational fixed dielectric constant or index of refraction. station established for the automatic re- transmission of radio communications regional EMS system—An emergency received from any station in the mobile medical service area (trade, catchment, service. market, patient flow, geographic or governmental) that provides essentially all repeater station, re-modulating—A of the definitive emergency medical care for microwave repeater station in which the all emergencies and for the most critically ill signal is demodulated to the original and injured patients within the area. baseband frequencies and re-injected onto the modulator for transmission to the distant relay—Transmission forwarded through an station. intermediate station. resource management center—A center relay station—Radio stations that responsible for the allocation of those rebroadcast signals the instant they are resources essential to the most effective and received, so that the signal can be passed on efficient resolution, or management or both, to another station outside the range of the of the immediate problem. In most originating transmitter. communities these resources include police, fire and emergency medical services. The reliability—The ability of an item to resource management center is most perform a required function under stated effective when its responsibilities conditions for a stated period of time. encompass the whole of public safety response. remote base station—A base station located away from the operating console, to ringback—In a public safety answering take advantage of improved coverage center, permits the answering point to ring offered by a better geographical location. the hung-up telephone on a held circuit. The feature is useful when calling a party has remote control—The operation of a device failed to provide all necessary information to from a distance either electrically or by the answering point before hanging up. radio waves. ringdown—A type of signaling employed remote control equipment—The apparatus in manual operation telephone (as compared used for performing monitoring, controlling, to dial) which utilizes a continuos or pulsing supervisory control, or a combination of a-c signal transmitted over the line. these functions at a distance by electrical means. S repeater—A combination of apparatus for schematic diagram—A diagram or drawing receiving either one-way or two-way which shows electrical connections of a radio or other electrical device by means of symbols which are used to represent the Signal—The form of a radio wave in components. relation to the frequency serving to convey intelligence in communication. search lock monitor—A receiving channel scanning scheme which lock the receiver on signal-to-noise ratio—The ratio of the the first channel received. intensity of the desired signal to that of the undesired noise signal, usually expressed in selective call—A system for alerting decibels. individual or groups of stations by means of coded signals. signal strength—A measure of the field intensity caused by a radio transmitter at a selectivity—The ability to select one particular location within its operating particular signal from other signals at nearby range. Usually expressed as microvolts, or frequencies. This specification is important millivolts of signal. in urban areas where radio spectrum congestion exists. The more negative the simplex—1) —single frequency operation dB rating, the better the specification. whereby all base stations and mobiles operate on one common frequency, (2) selective routing—A routing of telephone operation on two different frequencies in a call to terminate at a PSAP determined by system that can communicate in two the location of the calling telephone. This is directions, but not simultaneously, such as accomplished by using a computer to when a base station and a mobile radio process the calling telephone number. operate on reversed pairs of frequencies without duplexing. sensitivity—The characteristic of a radio receiver which determines the minimum simplex channel—a communication input signal strength required for a given channel providing transmission in one signal output. In FM, sensitivity is the signal direction only at any given time. For level required to produce e a given ratio comparison see duplex channel. of signal to noise. The more sensitive a receiver is, the weaker the signal it can simplex operation—A method of radio receive. operation in which communication between two stations takes place in only one service channel—In a microwave system, a direction at a time. This includes ordinary voice channel fused for maintenance and transmit-receive operation, press-to-talk fault location. Also called order wire. operation, voice-operated transmit, and other forms of manual or automatic switching service life—The life expectancy of from transmit to receive. Also called equipment under normal conditions of use. simplex. side tone—The signal that reaches a SINAD —The ratio of signal plus noise plus telephone receiver from the transmitter of distortion to the noise plus distortion; the same set by way of a local path within expressed in decibels. An EIA standard the set. method of measuring receiver sensitivity. Basically a measure of RF signal strength that will result in a readable signal. Measured in percent of the carrier. The siren—An acoustical or electromechanical lower the percentage the better the stability. device used as a warning signal on emergency vehicles. standing wave ratio (SWR) —A measure of the amount of lost transmitting power due solid state—Denoting the use of to impedance differences between the instead of transmission line and the antenna. The ratio vacuum tubes or relays. of reflected to incident waves that exists at some particular point on a Special Emergency Radio Service (SERS) transmission line. —That portion of radio communications frequency resources authorized by the FCC statewide EMS system—A network of for use in the alleviation of emergency EMS systems, integrated and coordinated at situations endangering life or property. the state level. See FCC Part 90. strip chart recorder—An spectrum—A continuous range of electromechanical device used to make frequencies arranged in order of wavelength paperchart recordings of EKG information. or frequency within which Usually it uses a heat-sensitive paper and a waves have some common characteristics, heated stylus. such as audio spectrum, radio spectrum, etc. The entire range of electromagnetic subcarrier—A frequency sensitive device radiation extending from the longest known used to generate a modulated wave which in radio waves to the shortest known cosmic turn is applied as a modulating wave to rays. modulate another carrier. For EMS telemetry the subcarrier frequency is 1400 spurious response—The response of a Hz. radio receiver to an undesired frequency. supergroup—In microwave systems groups squelch—A circuit function that acts to of 60 channels each, occupying a particular suppress the audio output of a receiver when range of frequencies. noise power exceeding a predetermined level is present. switched network—A complex of diversified channels and equipment that squelch, carrier—A squelch system that automatically routes communications responds to the presence of an RF carrier between the calling and called signal. person or data equipment. The public telephone system. squelch circuit—A circuit that reduces or lowers the noise that would otherwise be synchronization—The process of making heard in a radio receiver between the carrier at the receiving end of a line or transmissions. system match the frequency of the carrier at the transmitting end. stability, frequency—The ability of a radio transmitter to maintain any predetermined synthesizer, frequency—A highly precise frequency, such as its assigned frequency. crystal oscillator with frequency dividers used to provide the precise radio frequency. such as AT&T long-lines series 500 tariff A typical synthesizer can be set to small offering. frequency increments and have an accurate output at the desired output frequency. telephone line—A telephone lien from a telephone company central office that is system—A combination of two or more connected to key or non-key telephone stations in such a way as to provide equipment. communications. teletypewriter—An electromechanical T device, similar to a typewriter, such that messages typed on the keyboard of the tandem trunking—An arrangement where transmitter unit are converted into a telephone-line connection has one or more electrical signals, which when conveyed to intermediate points that are required or the receiver unit, are printed on paper. permitted usually on a controlled dial pulse basis before reaching the final destination ten signals—A series of coded messages (called) party. designed to reduce air transmission time and tariff—A document filed by a confusion in busy mobile radio systems. communications company with Public thermal noise—Very small noise voltages Utilities Commission which lists the that are present in all conductors, caused by services offered the public and schedule of the thermal agitation of charged particles rates and charges. within the conductor. tarnish—A discoloration or stain on the third harmonic—A frequency wave having surface of metal caused by exposure to three times the fundamental frequency chemicals or the atmosphere. To dull or value. destroy the luster of metal. threshold—In an FM receiver, the point at tee—A three-way connection in the shape of which the peaks of the incoming RF signal the letter t. exactly equal the peaks of the internally generated thermal noise power or the point telecommunications—All forms of above which increasing the input electrical transmission of intelligence signal strength provides only a dB for dB including: telegraph, telephone, radio, and improvement in the output signal-to-noise television. Pertaining to the art and science ration. of communication by these methods. tip—The ball-shaped contact on the cord telemetry—The sensing and measuring of (tip) of a plug. One of a pair of telephone information at some remote location and wires (the other of which is called the ring). transmitting the data to a convenient location to be read and recorded. tone—An audio or carrier of controlled amplitude and frequency used in a selective telpak—An acronym for “telephone signaling system or for equipment control package”, a schedule of bulk discount rates purposes. for multiple private line telephone services tone code—A specified character of circuit components for both transmitting and transmitted tone signals required to effect a receiving. particular selection or function. transformer—An electrical device for tone coded squelch—A system whereby a voltage current transformation, or superimposed tone is transmitted with the impedance matching or both. radio carrier to protect against nuisance type interference. transfer method—The PSAP interrogator determines the proper responding agency tone, Type 90—General Electric’s name for and connects the user to that agency. To a system of single tone signaling. The tones perform the necessary dispatching are generally between 1000 and 2400 Hz in in accordance with prearranged plans with two bands. cooperating agencies. tone, Type 99—General Electric’s name for transient—A rapid, sometimes violent, its two-tone sequential selective signaling fluctuation of voltage or current in a circuit system. Sometimes called Sel-Call. The usually of short duration caused by tones are generally between 520 and 953 Hz. switching or changes in load. topographic map—An accurately scaled transmitter—Apparatus for the production map having contour lines which show the and modulation of radio frequency energy elevation above sea level. Used in preparing for the purpose of radio communication. profiles of radio propagation paths. transmission line—A waveguide, coaxial touch pad—A method of signaling or line, or other system of conductors used to encoding and decoding address codes by the transfer signal energy efficiently from one use of a simple numerical push-button location to another. In communications keyboard. systems, the coaxial line between the base station and the antenna. Touchtone—A Bell System trademark used to describe their method of signaling and use trunk—A circuit used for connecting a of dual tone multifrequency (DTMF) tones. subscriber in a central office to all other services in/out of the switching equipment. tower, antenna—A tall antenna support structure used to support one or more trunk line—A telephone line that antennas or when an antenna must be terminates at a switchboard rather than a mounted high above the ground or other telephone. support formation such as a building. TSPS—An electronic operating position traffic—Used for messages handling by a system whereby operator-handled traffic is radio communications system. routed to its final destination via a central switching machine. transceiver—The combination of radio transmitting and receiving equipment in a turret—A section of communications common housing, usually for portable or control console, containing switches, mobile use, and employing common controls, meters, etc. varactor—A semiconductor diode used as a two-way radio—A radio that is able to variable capacitor. Used as a harmonic transmit and to receive. generator, frequency multiplier, and amplifier. two-wire operation—Uses a single pair (two wires) for both transmitting and vehicular repeater station—A mobile receiving. station in the mobile services authorized to retransmit automatically on a mobile service U frequency, communications originated by hand carried portable units or by other Ultra High Frequency (UHF)— mobile or base stations directed to such Frequencies between 300 and 3000 MHz. hand-carried units. ultrasonic—Describing frequencies higher Versatone—General Electric company than those which are audible. Generally trade name for a solid state tuned tone above 20000 Hz. determining element. unbalanced line—A transmission line in vertical antenna—A vertical steel tower, which the voltages on the two conductors rod or shaft used as an antenna. are unequal. Very High Frequency (VHF)—Frequency Underwriters Laboratories, Inc.—A between 30 and 300 MHz. laboratory sponsored by the National board of Fire Underwriters which examines and Vibrasponder—Motorola Communications tests devices, material and equipment company trade name for a tone determining whose action may affect casualty, fire, and vibrating reed element. life hazard. voice grade—A communications circuit unmodulated—Without modulation; the RF which is nominally 300 to 3000 Hz. carrier signal alone as it exists during pauses in conversations. voltage standing wave ratio (VSWR)— The ratio of the upper sideband—The higher of two maximum voltage to the minimum voltage frequencies or groups of frequencies along a transmission line. It is the measure produced by a modulation process. of the mismatch between the load and the line. utility—A power, gas, or water service available to the public. volume control—A potentiometer voltage divider used to V adjust the loudness of an audio circuit.

Van Allen belts—Radiation belts that volume unit (VU)—A measure of the surround the earth, consisting of electrons magnitude of sound and protons at high energy levels. from an electrical wave. Measured in decibels.

voting—Automatic selection of remote radio receiver. Al incoming signals are weatherproof—So constructed or protected compared for signal strength and the first that exposure to the weather elements will signal found that meets or exceeds a not prevent proper operation. preset level is selected and sent to the audio amplifier. weathertight—So constructed that exposure to a driven rain will not result in the W entrance of water.

watt—The unit of power. wire—A single metallic conductor.

wattmeter—A meter to indicate the rate at which electrical energy is being used or produced.

wave—A propagated periodic disturbance such as a radio, light or sound wave.

waveguide—A transmission line comprising a hollow conducting tube within which electromagnetic waves may be propagated. Generally used in microwave communications systems.

wavelength—The distance measured along the direction of propagation between tow points that are in phase on adjacent waves. A wavelength is the distance traveled by a wave in the time of one cycle. Electromagnetic waves included both light and radio waves and travel in space at approximately 300,000,000 m/s. To determine the exact length of a wave, divide 300,000,000 m by the frequency in hertz. wave, radio—An electro-magnetic wave which travels through space at the speed of light. wave, refracted—A radio wave that is bent (refracted) as it travels into a second medium of propagation, such as from the atmosphere to the ionized layers of the stratosphere.

ADDENDUM

Interoperability Channel Naming Names for Channels Coordinated/Managed by CalSIEC April 4, 2008 - Subscriber Programming Shown

.5 kHz) only with original FCC name shown N = 12.5 kHz bandwidth MW = 20 kHz bandwidth W = 25 kHz ebanding/Narrowbanding (Legacy Names) Post-Rebanding/Narrowbanding Rx Tx Short Name Rx Tx FREQ Rx CTCSS FREQ Tx CTCSS Bandwidth NPSTC Name (6 char) FREQ Rx CTCSS FREQ Tx VHF LOW BAND VHF LOW BAND 39.4600 156.7 45.8600 156.7 W LLAW1 LLAW1 39.4600 156.7 45.8600 1 39.4600 156.7 Simplex 156.7 W LLAW1D LLAW1D 39.4600 156.7 Simplex 1 39.4800 is used by various agencies in California LFIRE2 (pend) LFIRE2 39.4800 156.7 Simplex 1 ut 45.8600 156.7 Simplex 156.7 W LLAW3D LLAW3D 45.8600 156.7 Simplex 1 45.8800 156.7 Simplex 156.7 W LFIRE4 LFIRE4 45.8800 156.7 Simplex 1 VHF HIGH BAND VHF HIGH BAND 155.7525 none Simplex none N VCALL10 VCAL10 155.7525 156.7 Simplex 1 151.1375 none Simplex none N VTAC11 VTAC11 151.1375 156.7 Simplex 1 154.4525 none Simplex none N VTAC12 VTAC12 154.4525 156.7 Simplex 1 158.7375 none Simplex none N VTAC13 VTAC13 158.7375 156.7 Simplex 1 159.4725 none Simplex none N VTAC14 VTAC14 159.4725 156.7 Simplex 1 VTAC17 VTAC17 161.8500 156.7 157.2500 1 VTAC17D TAC17D 161.8500 156.7 Simplex 1 VTAC18 VTAC18 161.8250 156.7 157.2250 1 VTAC18D TAC18D 161.8250 156.7 Simplex 1 154.2800 none Simplex none W VFIRE21 VFRE21 154.2800 156.7 Simplex 1 154.2650 none Simplex none W VFIRE22 VFRE22 154.2650 156.7 Simplex 1 154.2950 none Simplex none W VFIRE23 VFRE23 154.2950 156.7 Simplex 1 VFIRE24 VFRE24 154.2725 156.7 Simplex 1 VFIRE25 VFRE25 154.2875 156.7 Simplex 1 VFIRE26 VFRE26 154.3025 156.7 Simplex 1 VMED28 VMED28 155.3400 156.7 Simplex 1 VMED29 VMED29 155.3475 156.7 Simplex 1 155.4750 none Simplex none W VLAW31 VLAW31 155.4750 156.7 Simplex 1 VLAW32 VLAW32 155.4825 156.7 Simplex 1 Rx Tx Short Name Rx Tx FREQ Rx CTCSS FREQ Tx CTCSS Bandwidth NPSTC Name (6 char) FREQ Rx CTCSS FREQ Tx 154.9200 none Simplex Varies W CALAW1 CALAW1 154.9200 none Simplex 1 154.9350 none Simplex Varies W CALAW2 CALAW2 154.9350 none Simplex 1 156.0750 none Simplex none W CALCORD CACORD 156.0750 none Simplex N UHF UHF 453.2125 none 458.2125 none N UCALL40 UCAL40 453.2125 none 458.2125 1 453.2125 none Simplex none N UCALL40D CAL40D 453.2125 none Simplex 1 453.4625 none 458.4625 none N UTAC41 UTAC41 453.4625 none 458.4625 1 453.4625 none Simplex none N UTAC41D TAC41D 453.4625 none Simplex 1 453.7125 none 458.7125 none N UTAC42 UTAC42 453.7125 none 458.7125 1 453.7125 none Simplex none N UTAC42D TAC42D 453.7125 none Simplex 1 453.8625 none 458.8625 none N UTAC43 UTAC43 453.8625 none 458.8625 1 453.8625 none Simplex none N UTAC43D TAC43D 453.8625 none Simplex 1 460.0250 Varies 465.0250 Varies W CALAW4 CALAW4 460.0250 156.7 465.0250 V 460.0250 Varies Simplex Varies W CALAW4D CLAW4D 460.0250 156.7 Simplex V 484.2125 167.9 487.2125 146.2 W SCMA C SCMA C 484.2125 167.9 487.2125 1 484.2125 167.9 487.2125 167.9 W SCMA E SCMA E 484.2125 167.9 487.2125 1 484.2125 167.9 487.2125 156.7 W SCMA N SCMA N 484.2125 167.9 487.2125 1 484.2125 167.9 487.2125 173.8 W SCMA W SCMA W 484.2125 167.9 487.2125 1 484.2125 167.9 Simplex 167.9 W SCMA D SCMA D 484.2125 167.9 Simplex 1 484.2375 none Simplex 156.7 W CALAW5D CLAW5D 484.2375 156.7 Simplex 1 487.2375 none Simplex 156.7 W FDUMA FDUMA 487.2375 156.7 Simplex 1 800 MHz 800 MHz 866.0125 156.7 821.0125 156.7 MW 8CALL90 CAL90 851.0125 156.7 806.0125 1 866.0125 156.7 Simplex 156.7 MW 8CALL90D CAL90D 851.0125 156.7 Simplex 1 866.5125 156.7 821.5125 156.7 MW 8TAC91 TAC91 851.5125 156.7 806.5125 1 866.5125 156.7 Simplex 156.7 MW 8TAC91D TAC91D 851.5125 156.7 Simplex 1 867.0125 156.7 822.0125 156.7 MW 8TAC92 TAC92 852.0125 156.7 807.0125 1 867.0125 156.7 Simplex 156.7 MW 8TAC92D TAC92D 852.0125 156.7 Simplex 1 867.5125 156.7 822.5125 156.7 MW 8TAC93 TAC93 852.5125 156.7 807.5125 1 867.5125 156.7 Simplex 156.7 MW 8TAC93D TAC93D 852.5125 156.7 Simplex 1 868.0125 156.7 823.0125 156.7 MW 8TAC94 TAC94 853.0125 156.7 808.0125 1 868.0125 156.7 Simplex 156.7 MW 8TAC94D TAC94D 853.0125 156.7 Simplex 1 868.5125 none 823.5125 156.7 MW CALAW8 CALAW8 853.5125 156.7 808.5125 1 868.5125 none Simplex 156.7 MW CALAW8D CLAW8D 853.5125 156.7 Simplex 1 Rx Tx Rx Tx FREQ Rx CTCSS FREQ Tx CTCSS Bandwidth NPSTC Name Short Name (6 char) FREQ Rx CTCSS FREQ Tx 866.2000 none 821.2000 156.7 MW CALAW9 CALAW9 851.2000 156.7 806.2000 1 866.2000 none Simplex 156.7 MW CALAW9D CLAW9D 851.2000 156.7 Simplex 1 868.9875 156.7 823.9875 156.7 MW CAFIRE1 CFIRE1 853.9875 156.7 808.9875 1 868.9875 156.7 Simplex 156.7 MW CAFIRE1D CFRE1D 853.9875 156.7 Simplex 1 866.9125 156.7 821.9125 156.7 MW CAFIRE2 CFIRE2 851.9125 156.7 806.9125 1 866.9125 156.7 Simplex 156.7 MW CAFIRE2D CFRE2D 851.9125 156.7 Simplex 1

Only: Reno VHF Public Coast Service Area #34, including California counties of Alpine, Inyo, Lassen, Mono, Plumas and Sierra.

Only: Southern California UHF TV-Band sharing area (primarily LA County).

Only: NPSPAC Region 6 (48 Northern California counties).