[Code of Federal Regulations]

[Title 47, Volume 1]

[Revised as of October 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 47CFR15.109]



[Page 782-783]

 

                       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.



[[Page 783]]



    (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 Third Edition of the 

International Special Committee on Radio Interference (CISPR), Pub. 22, 

``Information Technology Equipment--Radio Disturbance Characteristics--

Limits and Methods of Measurement'' (incorporated by reference, see 

Sec. 15.38). In addition:

    (1) The test procedure and other requirements specified in this part 

shall continue to apply to digital devices.

    (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).

    (h) Radar detectors shall comply with the emission limits in 

paragraph (a) of this section over the frequency range of 11.7-12.2 GHz.



[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; 67 FR 48993, July 

29, 2002; 69 FR 2849, Jan. 21, 2004]