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Copyright 1999-2015

FCC Part 15 Radio Frequency Devices
Section 15.3

The Federal Communications Commission (FCC) is the authority in the United States of America that creates and enforces the use of airwaves throughout the entire radio frequency spectrum. This group of documents contains the entirety of the FCC Part 15 regulations that concern unlicensed radio frequency devices. As with all government documents, this material is in the public domain and may be freely copied so long as the content is not changed. This copy is provided as a convenience for RF Cafe visitors. 

Click here for the Table of Contents.

[Code of Federal Regulations]
[Title 47, Volume 1]
[Revised as of October 1, 2008]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR15.3]
[Page 748-751]
                       TITLE 47--TELECOMMUNICATION
                            Subpart A_General
Sec. 15.3  Definitions.
    (a) Auditory assistance device. An intentional radiator used to 
provide auditory assistance to a handicapped person or persons. Such a 
device may be used for auricular training in an education institution, 
for auditory assistance at places of public gatherings, such as a 
church, theater, or auditorium, and for auditory assistance to 
handicapped individuals, only, in other locations.
    (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 allocated for Citizens Band (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
[[Page 749]]
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 
    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
[[Page 750]]
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 
    (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 
    (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 
    (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 Sec. 15.118 and the provisions of Sec. 
    (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 
    (1) A circuit board that contains only a microprocessor intended to 
[[Page 751]]
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 Sec. 15.3(t) or In-House BPL 
as defined in Sec. 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.
[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]


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