[Code of Federal Regulations]
[Title 47, Volume 1]
[Revised as of October 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR15.109]
[Page 690-691]
TITLE 47--TELECOMMUNICATION
CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION
PART 15--RADIO FREQUENCY DEVICES--Table of Contents
Subpart B--Unintentional Radiators
Sec. 15.109 Radiated emission limits.
(a) Except for Class A digital devices, the field strength of
radiated emissions from unintentional radiators at a distance of 3
meters shall not exceed the following values:
------------------------------------------------------------------------
Field
strength
Frequency of emission (MHz) (microvolts/
meter)
------------------------------------------------------------------------
30-88..................................................... 100
88-216.................................................... 150
216-960................................................... 200
Above 960................................................. 500
------------------------------------------------------------------------
(b) The field strength of radiated emissions from a Class A digital
device, as determined at a distance of 10 meters, shall not exceed the
following:
------------------------------------------------------------------------
Field
strength
Frequency of emission (MHz) (microvolts/
meter)
------------------------------------------------------------------------
30-88..................................................... 90
88-216.................................................... 150
216-960................................................... 210
Above 960................................................. 300
------------------------------------------------------------------------
(c) In the emission tables above, the tighter limit applies at the
band edges. Sections 15.33 and 15.35 which specify the frequency range
over which radiated emissions are to be measured and the detector
functions and other measurement standards apply.
(d) For CB receivers, the field strength of radiated emissions
within the frequency range of 25-30 MHz shall not exceed 40 microvolts/
meter at a distance of 3 meters. The field strength of radiated
emissions above 30 MHz from such devices shall comply with the limits in
paragraph (a) of this section.
(e) Carrier current systems used as unintentional radiators or other
unintentional radiators that are designed to conduct their radio
frequency emissions via connecting wires or cables and that operate in
the frequency range of 9 kHz to 30 MHz, including devices that deliver
the radio frequency energy to transducers, such as ultrasonic devices
not covered under part 18 of this chapter, shall comply with the
radiated emission limits for intentional radiators provided in
Sec. 15.209 for the frequency range of 9 kHz to 30 MHz. As an
alternative, carrier current systems used as unintentional radiators and
operating in the frequency range of 525 kHz to 1705 kHz may comply with
the radiated emission limits provided in Sec. 15.221(a). At frequencies
above 30 MHz, the limits in paragraph (a), (b), or (g) of this section,
as appropriate, apply.
(f) For a receiver which employs terminals for the connection of an
external receiving antenna, the receiver shall be tested to demonstrate
compliance with the provisions of this section with an antenna connected
to the antenna terminals unless the antenna conducted power is measured
as specified in Sec. 15.111(a). If a permanently attached receiving
antenna is used, the receiver shall be tested to demonstrate compliance
with the provisions of this section.
(g) As an alternative to the radiated emission limits shown in
paragraphs (a) and (b) of this section, digital devices may be shown to
comply with the standards contained in the Third Edition of
International Electrotechnical Commission (``IEC''), International
Special Committee on Radio Interference (CISPR) Pub. 22 (1997),
``Information Technology Equipment--Radio Disturbance Characteristics--
Limits and Methods of Measurement.'' This incorporation by reference was
approved by the Director of the Federal Register in accordance with 5
U.S.C. 552(a) and 1 CFR part 51. Copies of CISPR publications may be
purchased from the Global Engineering Documents, P. O. Box 8500 (S-
4485), Philadelphia, PA 19178-4485, (303) 792-2181 or (800) 624-3974.
Copies also may be inspected, but not reproduced, during normal business
hours at the following locations: Federal Communications Commission,
Reference Information Center, Room CY-A257, 445 12th Street, SW.,
Washington, DC, and Office of the Federal Register, 800 North Capitol
Street, NW., Suite 700, Washington, DC. In addition:
(1) The test procedure and other requirements specified in this part
shall continue to apply to digital devices.
[[Page 691]]
(2) If, in accordance with Sec. 15.33 of this part, measurements
must be performed above 1000 MHz, compliance above 1000 MHz shall be
demonstrated with the emission limit in paragraph (a) or (b) of this
section, as appropriate. Measurements above 1000 MHz may be performed at
the distance specified in the CISPR 22 publications for measurements
below 1000 MHz provided the limits in paragraphs (a) and (b) of this
section are extrapolated to the new measurement distance using an
inverse linear distance extrapolation factor (20 dB/decade), e.g., the
radiated limit above 1000 MHz for a Class B digital device is 150 uV/m,
as measured at a distance of 10 meters.
(3) The measurement distances shown in CISPR Pub. 22, including
measurements made in accordance with this paragraph above 1000 MHz, are
considered, for the purpose of Sec. 15.31(f)(4) of this part, to be the
measurement distances specified in this part.
(4) If the radiated emissions are measured to demonstrate compliance
with the alternative standards in this paragraph, compliance must also
be demonstrated with the conducted limits shown in Sec. 15.107(e).
[54 FR 17714, Apr. 25, 1989, as amended at 56 FR 373, Jan. 4, 1991; 58
FR 51249, Oct. 1, 1993; 66 FR 19098, Apr. 13, 2001]