§  15.3   Definitions.

   (a) Auditory assistance device. An intentional radiator used to provide
   auditory assistance communications (including but not limited to
   applications such as assistive listening, auricular training, audio
   description for the blind, and simultaneous language translation) for:

   (1) Persons with disabilities: In the context of part 15 rules (47 CFR
   part 15), the term "disability," with respect to the individual, has
   the meaning given to it by section 3(2)(A) of the Americans with
   Disabilities Act of 1990 (42 U.S.C. 12102(2)(A)), i.e., a physical or
   mental impairment that substantially limits one or more of the major
   life activities of such individuals;

   (2) Persons who require language translation; or

   (3) Persons who may otherwise benefit from auditory assistance
   communications in places of public gatherings, such as a church,
   theater, auditorium, or educational institution.

   (b) Biomedical telemetry device. An intentional radiator used to
   transmit measurements of either human or animal biomedical phenomena to
   a receiver.

   (c) Cable input selector switch. A transfer switch that is intended as
   a means to alternate between the reception of broadcast signals via
   connection to an antenna and the reception of cable television service.

   (d) Cable locating equipment. An intentional radiator used
   intermittently by trained operators to locate buried cables, lines,
   pipes, and similar structures or elements. Operation entails coupling a
   radio frequency signal onto the cable, pipes, etc. and using a receiver
   to detect the location of that structure or element.

   (e) Cable system terminal device (CSTD). A TV interface device that
   serves, as its primary function, to connect a cable system operated
   under part 76 of this chapter to a TV broadcast receiver or other
   subscriber premise equipment. Any device which functions as a CSTD in
   one of its operating modes must comply with the technical requirements
   for such devices when operating in that mode.

   (f) Carrier current system. A system, or part of a system, that
   transmits radio frequency energy by conduction over the electric power
   lines. A carrier current system can be designed such that the signals
   are received by conduction directly from connection to the electric
   power lines (unintentional radiator) or the signals are received
   over-the-air due to radiation of the radio frequency signals from the
   electric power lines (intentional radiator).

   (g) CB receiver. Any receiver that operates in the Personal Radio
   Services on frequencies designated for CB Radio Service stations, as
   well as any receiver provided with a separate band specifically
   designed to receive the transmissions of CB stations in the Personal
   Radio Services. This includes the following:

   (1) A CB receiver sold as a separate unit of equipment;

   (2) The receiver section of a CB transceiver;

   (3) A converter to be used with any receiver for the purpose of
   receiving CB transmissions; and

   (4) A multiband receiver that includes a band labelled "CB" or
   "11-meter" in which such band can be separately selected, except that
   an Amateur Radio Service receiver that was manufactured prior to
   January 1, 1960, and which includes an 11-meter band shall not be
   considered to be a CB receiver.

   (h) Class A digital device. A digital device that is marketed for use
   in a commercial, industrial or business environment, exclusive of a
   device which is marketed for use by the general public or is intended
   to be used in the home.

   (i) Class B digital device. A digital device that is marketed for use
   in a residential environment notwithstanding use in commercial,
   business and industrial environments. Examples of such devices include,
   but are not limited to, personal computers, calculators, and similar
   electronic devices that are marketed for use by the general public.

   Note: The responsible party may also qualify a device intended to be
   marketed in a commercial, business or industrial environment as a Class
   B device, and in fact is encouraged to do so, provided the device
   complies with the technical specifications for a Class B digital
   device. In the event that a particular type of device has been found to
   repeatedly cause harmful interference to radio communications, the
   Commission may classify such a digital device as a Class B digital
   device, regardless of its intended use.

   (j) Cordless telephone system. A system consisting of two transceivers,
   one a base station that connects to the public switched telephone
   network and the other a mobile handset unit that communicates directly
   with the base station. Transmissions from the mobile unit are received
   by the base station and then placed on the public switched telephone
   network. Information received from the switched telephone network is
   transmitted by the base station to the mobile unit.

   Note: The Domestic Public Cellular Radio Telecommunications Service is
   considered to be part of the switched telephone network. In addition,
   intercom and paging operations are permitted provided these are not
   intended to be the primary modes of operation.

   (k) Digital device. (Previously defined as a computing device). An
   unintentional radiator (device or system) that generates and uses
   timing signals or pulses at a rate in excess of 9,000 pulses (cycles)
   per second and uses digital techniques; inclusive of telephone
   equipment that uses digital techniques or any device or system that
   generates and uses radio frequency energy for the purpose of performing
   data processing functions, such as electronic computations, operations,
   transformations, recording, filing, sorting, storage, retrieval, or
   transfer. A radio frequency device that is specifically subject to an
   emanation requirement in any other FCC Rule part or an intentional
   radiator subject to subpart C of this part that contains a digital
   device is not subject to the standards for digital devices, provided
   the digital device is used only to enable operation of the radio
   frequency device and the digital device does not control additional
   functions or capabilities.

   Note: Computer terminals and peripherals that are intended to be
   connected to a computer are digital devices.

   (l) Field disturbance sensor. A device that establishes a radio
   frequency field in its vicinity and detects changes in that field
   resulting from the movement of persons or objects within its range.

   (m) Harmful interference. Any emission, radiation or induction that
   endangers the functioning of a radio navigation service or of other
   safety services or seriously degrades, obstructs or repeatedly
   interrupts a radiocommunications service operating in accordance with
   this chapter.

   (n) Incidental radiator. A device that generates radio frequency energy
   during the course of its operation although the device is not
   intentionally designed to generate or emit radio frequency energy.
   Examples of incidental radiators are dc motors, mechanical light
   switches, etc.

   (o) Intentional radiator. A device that intentionally generates and
   emits radio frequency energy by radiation or induction.

   (p) Kit. Any number of electronic parts, usually provided with a
   schematic diagram or printed circuit board, which, when assembled in
   accordance with instructions, results in a device subject to the
   regulations in this part, even if additional parts of any type are
   required to complete assembly.

   (q) Perimeter protection system. A field disturbance sensor that
   employs RF transmission lines as the radiating source. These RF
   transmission lines are installed in such a manner that allows the
   system to detect movement within the protected area.

   (r) Peripheral device. An input/output unit of a system that feeds data
   into and/or receives data from the central processing unit of a digital
   device. Peripherals to a digital device include any device that is
   connected external to the digital device, any device internal to the
   digital device that connects the digital device to an external device
   by wire or cable, and any circuit board designed for interchangeable
   mounting, internally or externally, that increases the operating or
   processing speed of a digital device, e.g., "turbo" cards and
   "enhancement" boards. Examples of peripheral devices include terminals,
   printers, external floppy disk drives and other data storage devices,
   video monitors, keyboards, interface boards, external memory expansion
   cards, and other input/output devices that may or may not contain
   digital circuitry. This definition does not include CPU boards, as
   defined in paragraph (bb) of this section, even though a CPU board may
   connect to an external keyboard or other components.

   (s) Personal computer. An electronic computer that is marketed for use
   in the home, notwithstanding business applications. Such computers are
   considered Class B digital devices. Computers which use a standard TV
   receiver as a display device or meet all of the following conditions
   are considered examples of personal computers:

   (1) Marketed through a retail outlet or direct mail order catalog.

   (2) Notices of sale or advertisements are distributed or directed to
   the general public or hobbyist users rather than restricted to
   commercial users.

   (3) Operates on a battery or 120 volt electrical supply.

   If the responsible party can demonstrate that because of price or
   performance the computer is not suitable for residential or hobbyist
   use, it may request that the computer be considered to fall outside of
   the scope of this definition for personal computers.

   (t) Power line carrier systems. An unintentional radiator employed as a
   carrier current system used by an electric power utility entity on
   transmission lines for protective relaying, telemetry, etc. for general
   supervision of the power system. The system operates by the
   transmission of radio frequency energy by conduction over the electric
   power transmission lines of the system. The system does not include
   those electric lines which connect the distribution substation to the
   customer or house wiring.

   (u) Radio frequency (RF) energy. Electromagnetic energy at any
   frequency in the radio spectrum between 9 kHz and 3,000,000 MHz.

   (v) Scanning receiver. For the purpose of this part, this is a receiver
   that automatically switches among two or more frequencies in the range
   of 30 to 960 MHz and that is capable of stopping at and receiving a
   radio signal detected on a frequency. Receivers designed solely for the
   reception of the broadcast signals under part 73 of this chapter, for
   the reception of NOAA broadcast weather band signals, or for operation
   as part of a licensed service are not included in this definition.

   (w) Television (TV) broadcast receiver. A device designed to receive
   television pictures that are broadcast simultaneously with sound on the
   television channels authorized under part 73 of this chapter.

   (x) Transfer switch. A device used to alternate between the reception
   of over-the-air radio frequency signals via connection to an antenna
   and the reception of radio frequency signals received by any other
   method, such as from a TV interface device.

   (y) TV interface device. An unintentional radiator that produces or
   translates in frequency a radio frequency carrier modulated by a video
   signal derived from an external or internal signal source, and which
   feeds the modulated radio frequency energy by conduction to the antenna
   terminals or other non-baseband input connections of a television
   broadcast receiver. A TV interface device may include a stand-alone RF
   modulator, or a composite device consisting of an RF modulator, video
   source and other components devices. Examples of TV interface devices
   are video cassette recorders and terminal devices attached to a cable
   system or used with a Master Antenna (including those used for central
   distribution video devices in apartment or office buildings).

   (z) Unintentional radiator. A device that intentionally generates radio
   frequency energy for use within the device, or that sends radio
   frequency signals by conduction to associated equipment via connecting
   wiring, but which is not intended to emit RF energy by radiation or
   induction.

   (aa) Cable ready consumer electronics equipment. Consumer electronics
   TV receiving devices, including TV receivers, videocassette recorders
   and similar devices, that incorporate a tuner capable of receiving
   television signals and an input terminal intended for receiving cable
   television service, and are marketed as "cable ready" or "cable
   compatible." Such equipment shall comply with the technical standards
   specified in § 15.118 and the provisions of § 15.19(d).

   (bb) CPU board. A circuit board that contains a microprocessor, or
   frequency determining circuitry for the microprocessor, the primary
   function of which is to execute user-provided programming, but not
   including:

   (1) A circuit board that contains only a microprocessor intended to
   operate under the primary control or instruction of a microprocessor
   external to such a circuit board; or

   (2) A circuit board that is a dedicated controller for a storage or
   input/output device.

   (cc) External radio frequency power amplifier. A device which is not an
   integral part of an intentional radiator as manufactured and which,
   when used in conjunction with an intentional radiator as a signal
   source, is capable of amplifying that signal.

   (dd) Test equipment is defined as equipment that is intended primarily
   for purposes of performing measurements or scientific investigations.
   Such equipment includes, but is not limited to, field strength meters,
   spectrum analyzers, and modulation monitors.

   (ee) Radar detector. A receiver designed to signal the presence of
   radio signals used for determining the speed of motor vehicles. This
   definition does not encompass the receiver incorporated within a radar
   transceiver certified under the Commission's rules.

   (ff) Access Broadband over Power Line (Access BPL). A carrier current
   system installed and operated on an electric utility service as an
   unintentional radiator that sends radio frequency energy on frequencies
   between 1.705 MHz and 80 MHz over medium voltage lines or over low
   voltage lines to provide broadband communications and is located on the
   supply side of the utility service's points of interconnection with
   customer premises. Access BPL does not include power line carrier
   systems as defined in § 15.3(t) or In-House BPL as defined in § 15.3(gg).

   (gg) In-House Broadband over Power Line (In-House BPL). A carrier
   current system, operating as an unintentional radiator, that sends
   radio frequency energy by conduction over electric power lines that are
   not owned, operated or controlled by an electric service provider. The
   electric power lines may be aerial (overhead), underground, or inside
   the walls, floors or ceilings of user premises. In-House BPL devices
   may establish closed networks within a user's premises or provide
   connections to Access BPL networks, or both.

   (hh) Slant-Range distance. Diagonal distance measured from the center
   of the measurement antenna to the nearest point of the overhead power
   line carrying the Access BPL signal being measured. This distance is
   equal to the hypotenuse of the right triangle as calculated in the
   formula below. The slant-range distance shall be calculated as follows:
   eCFR graphic er21no11.002.gif

   View or download PDF

   Where:

   dslant is the slant-range distance, in meters (see Figure 1, below);

   dh is the horizontal (lateral) distance between the center of the
   measurement antenna and the vertical projection of the overhead power
   line carrying the BPL signals down to the height of the measurement
   antenna, in meters;

   hpwr_line is the height of the power line, in meters; and

   hant is the measurement antenna height, in meters.
   eCFR graphic er21no11.003.gif

   View or download PDF

   Dslant is the slant-range distance, in meters;

   Dh is the horizontal (lateral) distance between the center of the
   measurement antenna and the vertical projection of the overhead power
   line carrying the BPL signals down to the height of the measurement
   antenna, in meters;

   Dlimit is the distance at which the emission limit is specified in Part
   15 (e.g., 30 meters for frequencies below 30 MHz);

   Hpwr_line is the height of the power line, in meters; and

   Hant is the measurement antenna height, in meters.

   (ii) Level Probing Radar (LPR): A short-range radar transmitter used in
   a wide range of applications to measure the amount of various
   substances, mostly liquids or granulates. LPR equipment may operate in
   open-air environments or inside an enclosure containing the substance
   being measured.

   [ 54 FR 17714 , Apr. 25, 1989, as amended at  55 FR 18340 , May 2, 1990;  57 FR 33448 , July 29, 1992;  59 FR 25340 , May 16, 1994;  61 FR 31048 , June
   19, 1996;  62 FR 26242 , May 13, 1997;  64 FR 22561 , Apr. 27, 1999;  65 FR 64391 , Oct. 27, 2000;  66 FR 32582 , June 15, 2001;  67 FR 48993 , July 29,
   2002;  70 FR 1373 , Jan. 7, 2005;  76 FR 71907 , Nov. 21, 2011;  78 FR 34927 , June 11, 2013;  79 FR 12677 , Mar. 6, 2014;  82 FR 41103 , Aug. 29,
   2017]