§  2.1043   Changes in certificated equipment.

   (a) Except as provided in paragraph (b)(3) of this section, changes to
   the basic frequency determining and stabilizing circuitry (including
   clock or data rates), frequency multiplication stages, basic modulator
   circuit or maximum power or field strength ratings shall not be
   performed without application for and authorization of a new grant of
   certification. Variations in electrical or mechanical construction,
   other than these indicated items, are permitted provided the variations
   either do not affect the characteristics required to be reported to the
   Commission or the variations are made in compliance with the other
   provisions of this section. Changes to the software installed in a
   transmitter that do not affect the radio frequency emissions do not
   require a filing with the Commission and may be made by parties other
   than the holder of the grant of certification.

   (b) Three classes of permissive changes may be made in certificated
   equipment without requiring a new application for and grant of
   certification. None of the classes of changes shall result in a change
   in identification.

   (1) A Class I permissive change includes those modifications in the
   equipment which do not degrade the characteristics reported by the
   manufacturer and accepted by the Commission when certification is
   granted. No filing with the Commission is required for a Class I
   permissive change.

   (2) A Class II permissive change includes those modifications which
   degrade the performance characteristics as reported to the Commission
   at the time of the initial certification. Such degraded performance
   must still meet the minimum requirements of the applicable rules. When
   a Class II permissive change is made by the grantee, the grantee shall
   supply the Commission with complete information and the results of
   tests of the characteristics affected by such change. The modified
   equipment shall not be marketed under the existing grant of
   certification prior to acknowledgement by the Commission that the
   change is acceptable.

   (3) A Class III permissive change includes modifications to the
   software of a software defined radio transmitter that change the
   frequency range, modulation type or maximum output power (either
   radiated or conducted) outside the parameters previously approved, or
   that change the circumstances under which the transmitter operates in
   accordance with Commission rules. When a Class III permissive change is
   made, the grantee shall supply the Commission with a description of the
   changes and test results showing that the equipment complies with the
   applicable rules with the new software loaded, including compliance
   with the applicable RF exposure requirements. The modified software
   shall not be loaded into the equipment, and the equipment shall not be
   marketed with the modified software under the existing grant of
   certification, prior to acknowledgement by the Commission that the
   change is acceptable. Class III changes are permitted only for
   equipment in which no Class II changes have been made from the
   originally approved device.

   Note to paragraph (b)(3): Any software change that degrades spurious
   and out-of-band emissions previously reported to the Commission at the
   time of initial certification would be considered a change in frequency
   or modulation and would require a Class III permissive change or new
   equipment authorization application.

   (4) Class I and Class II permissive changes may only be made by the
   holder of the grant of certification, except as specified below.

   (c) A grantee desiring to make a change other than a permissive change
   shall file an application on FCC Form 731 accompanied by the required
   fees. The grantee shall attach a description of the change(s) to be
   made and a statement indicating whether the change(s) will be made in
   all units (including previous production) or will be made only in those
   units produced after the change is authorized.

   (d) A modification which results in a change in the identification of a
   device with or without change in circuitry requires a new application
   for, and grant of certification. If the changes affect the
   characteristics required to be reported, a complete application shall
   be filed. If the characteristics required to be reported are not
   changed the abbreviated procedure of § 2.933 may be used.

   (e) Equipment that has been certificated or formerly type accepted for
   use in the Amateur Radio Service pursuant to the requirements of part
   97 of this chapter may be modified without regard to the conditions
   specified in paragraph (b) of this section, provided the following
   conditions are met:

   (1) Any person performing such modifications on equipment used under
   part 97 of this chapter must possess a valid amateur radio operator
   license of the class required for the use of the equipment being
   modified.

   (2) Modifications made pursuant to this paragraph are limited to
   equipment used at licensed amateur radio stations.

   (3) Modifications specified or performed by equipment manufacturers or
   suppliers must be in accordance with the requirements set forth in
   paragraph (b) of this section.

   (4) Modifications specified or performed by licensees in the Amateur
   Radio Service on equipment other than that at specific licensed amateur
   radio stations must be in accordance with the requirements set forth in
   paragraph (b) of this section.

   (5) The station licensee shall be responsible for ensuring that
   modified equipment used at his station will comply with the applicable
   technical standards in part 97 of this chapter.

   (f) For equipment other than that operating under parts 15 or 18, when
   a Class II permissive change is made by other than the grantee of
   certification, the information and data specified in paragraph (b)(2)
   of this section shall be supplied by the person making the change. The
   modified equipment shall not be operated under an authorization of the
   Commission prior to acknowledgement by the Commission that the change
   is acceptable.

   (g) The interconnection of a certificated or formerly type accepted AM
   broadcast stereophonic exciter-generator with a certificated or
   formerly type accepted AM broadcast transmitter in accordance with the
   manufacturer's instructions and upon completion of measurements showing
   that the modified transmitter meets the emission limitation
   requirements of § 73.44 is defined as a Class I permissive change for
   compliance with this section.

   (h) The interconnection of a multiplexing exciter with a certificated
   or formerly type accepted AM broadcast transmitter in accordance with
   the manufacturer's instructions without electrical or mechanical
   modification of the transmitter circuits and completion of equipment
   performance measurements showing the transmitter meets the minimum
   performance requirements applicable thereto is defined as a Class I
   permissive change for compliance with this section.

   (i) The addition of TV broadcast subcarrier generators to a
   certificated or formerly type accepted TV broadcast transmitter or the
   addition of FM broadcast subcarrier generators to a type accepted FM
   broadcast transmitter, provided the transmitter exciter is designed for
   subcarrier operation without mechanical or electrical alterations to
   the exciter or other transmitter circuits.

   (j) The addition of TV broadcast stereophonic generators to a
   certificated or formerly type accepted TV broadcast transmitter or the
   addition of FM broadcast stereophonic generators to a certificated or
   formerly type accepted FM broadcast transmitter, provided the
   transmitter exciter is designed for stereophonic sound operation
   without mechanical or electrical alterations to the exciter or other
   transmitter circuits.

   (k) The addition of subscription TV encoding equipment for which the
   FCC has granted advance approval under the provisions of § 2.1400 in
   subpart M and § 73.644(c) of part 73 to a certificated or formerly type
   accepted transmitter is considered a Class I permissive change.

   (l) Notwithstanding the provisions of this section, broadcast licensees
   or permittees are permitted to modify certificated or formerly type
   accepted equipment pursuant to § 73.1690 of the FCC's rules.

   [ 63 FR 36600 , July 7, 1998, as amended at  66 FR 50840 , Oct. 5, 2001;  70 FR 23040 , May 4, 2005]