[Code of Federal Regulations]

[Title 47, Volume 2]

[Revised as of October 1, 2004]

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

[CITE: 47CFR21.42]



[Page 48-49]

 

                       TITLE 47--TELECOMMUNICATION

 

                    CHAPTER I--FEDERAL COMMUNICATIONS

                         COMMISSION (CONTINUED)

 

PART 21_DOMESTIC PUBLIC FIXED RADIO SERVICES--Table of Contents

 

                   Subpart B_Applications and Licenses

 

Sec. 21.42  Certain modifications not requiring prior authorization.



    (a) Equipment in an authorized radio station may be replaced without 

prior authorization or notification if:

    (1) The replacement equipment is identical (i.e., same manufacturer 

and model number) with the replacement equipment; or

    (2) The replacement transmitter, transmitting antenna, transmission 

line loss and/or devices between the



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transmitter and antenna, or combinations of the above, do not change the 

EIRP of a station in any direction.

    (b) Licensees of fixed stations in the Multipoint Distribution 

Service may make the facility changes listed in paragraph (c) of this 

section without obtaining prior Commission authorization, if:

    (1) The Multipoint Distribution Service licensee serves a copy of 

the notification described in paragraph (b)(3) of this section on those 

who were served under Sec. 21.902, and

    (2) The cumulative effect of all facility changes made within any 60 

day period does not exceed the appropriate values prescribed by 

paragraph (c) of this section, and

    (3) The Commission is notified of changes made to facilities by the 

submission of a completed FCC Form 304 within thirty (30) days after the 

changes are made.

    (4) In the Multipoint Distribution Service, the modified facility 

would not produce a power flux density at the protected service area 

boundary that exceeds -73 dBW/m\2\, pursuant to Sec. Sec. 21.902 and 

21.939.

    (c) Modifications that may be made without prior authorization under 

paragraph (b) of this section are:

    (1) Change or modification of a transmitter, when:

    (i) The replacement or modified transmitter is certificated for use 

under this part and is installed without modification from the 

certificated configuration;

    (ii) The type of modulation is not changed;

    (iii) The frequency stability is equal to or better than the 

previously authorized frequency stability; and

    (iv) The necessary bandwidth and the output power do not exceed the 

previously authorized values.

    (2) Addition or deletion of a transmitter for protection without 

changing the authorized power output (e.g. hot standby transmitters);

    (3) Change to an antenna when the new antenna conforms with Sec. 

21.906 and the EIRP resulting from the new antenna does not exceed that 

resulting from the previously authorized antenna by more than one dB in 

any direction.

    (4) Any technical changes that would decrease the effective radiated 

power.

    (5) Change to the height of an antenna, when:

    (i) The new height (measured at the center-of-radiation) is within 

1.5 meters (5 feet) of the previously authorized 

height; and

    (ii) The overall height of the antenna structure is not increased as 

a result of the antenna extending above the height of the previously 

authorized structure, except when the new height of the antenna 

structure is 6.1 meters (20 feet) or less (above ground or man-made 

structure, as appropriate) after the change is made.

    (6) Decreases in the overall height of an antenna structure, 

provided that, when notice to the FAA of proposed construction was 

required by part 17 of this chapter for the antenna structure at the 

previously authorized height, the applicant must comply with the 

provisions of Sec. 21.15 (d) and (e).

    (7) Changes to the transmission line and other devices between the 

transmitter and the antenna when the effective radiated power of the 

station is not increased by more than one dB.

    (8) A change to a sectorized antenna system comprising an array of 

directional antennas, provided that such system does not change 

polarization or result in an increase in radiated power by more than one 

dB in any horizontal or vertical direction; provided, however, that 

notice of such change is provided to the Commission on FCC Form 331 

within ten (10) days of installation.

    (d) Licensees may correct erroneous information on a license which 

does not involve a major change (i.e., a change that would be classified 

as a major amendment as defined by Sec. 21.23) without obtaining prior 

Commission approval by filing a completed FCC Form 494, or for the 

Multipoint Distribution Service licensees, by filing the MDS long-form 

application.



[52 FR 37781, Oct. 9, 1987, as amended at 58 FR 44894, Aug. 25, 1993; 60 

FR 36552, July 17, 1995; 60 FR 57366, Nov. 15, 1995; 61 FR 4364, Feb. 6, 

1996; 61 FR 26674, May 28, 1996; 63 FR 36603, July 7, 1998; 63 FR 49870, 

Sept. 18, 1998; 63 FR 65101, Nov. 25, 1998; 64 FR 4054, Jan. 27, 1999; 

65 FR 46617, July 31, 2000]



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