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Federal Communications Commission § 2.1046

of the Commission prior to acknowl- mitter is considered a Class I permis- edgement by the Commission that the sive change. change is acceptable. (l) Notwithstanding the provisions of (g) The interconnection of a certifi- this section, broadcast licensees or per- cated or formerly type accepted AM mittees are permitted to modify cer- broadcast stereophonic exciter-gener- tificated or formerly type accepted ator with a certificated or formerly equipment pursuant to § 73.1690 of the type accepted AM broadcast trans- FCC’s rules. mitter in accordance with the manu- [63 FR 36600, July 7, 1998, as amended at 66 facturer’s instructions and upon com- FR 50840, Oct. 5, 2001] pletion of measurements showing that the modified transmitter meets the § 2.1046 Measurements required: RF emission limitation requirements of power output. § 73.44 is defined as a Class I permissive (a) For transmitters other than sin- change for compliance with this sec- gle , and tion. controlled carrier , (h) The interconnection of a multi- power output shall be measured at the plexing exciter with a certificated or RF output terminals when the trans- formerly type accepted AM broadcast mitter is adjusted in accordance with transmitter in accordance with the the tune-up procedure to give the val- manufacturer’s instructions without ues of current and voltage on the cir- electrical or mechanical modification cuit elements specified in § 2.1033(c)(8). of the transmitter circuits and comple- The electrical characteristics of the tion of equipment performance meas- load attached to the urements showing the transmitter output terminals when this test is meets the minimum performance re- made shall be stated. quirements applicable thereto is de- (b) For single sideband, independent fined as a Class I permissive change for sideband, and single channel, con- compliance with this section. trolled carrier radiotelephone trans- (i) The addition of TV broadcast sub- mitters the procedure specified in para- carrier generators to a certificated or graph (a) of this section shall be em- formerly type accepted TV broadcast ployed and, in addition, the trans- transmitter or the addition of FM mitter shall be modulated during the broadcast generators to a test as follows. In all tests, the input type accepted FM broadcast trans- level of the modulating signal shall be mitter, provided the transmitter ex- such as to develop rated peak envelope citer is designed for subcarrier oper- power or carrier power, as appropriate, ation without mechanical or electrical for the transmitter. alterations to the exciter or other (1) Single sideband transmitters in transmitter circuits. the A3A or A3J emission modes—by (j) The addition of TV broadcast two tones at of 400 Hz and stereophonic generators to a certifi- 1800 Hz (for 3.0 kHz authorized band- cated or formerly type accepted TV width), or 500 Hz and 2100 Hz (3.5 kHz broadcast transmitter or the addition authorized ), or 500 Hz and of FM broadcast stereophonic genera- 2400 Hz (for 4.0 kHz authorized band- tors to a certificated or formerly type width), applied simultaneously, the accepted FM broadcast transmitter, input levels of the tones so adjusted provided the transmitter exciter is de- that the two principal frequency com- signed for oper- ponents of the signal ation without mechanical or electrical produced are equal in magnitude. alterations to the exciter or other (2) Single sideband transmitters in transmitter circuits. the A3H emission mode—by one tone at (k) The addition of subscription TV a frequency of 1500 Hz (for 3.0 kHz au- encoding equipment for which the FCC thorized bandwidth), or 1700 Hz (for 3.5 has granted advance approval under kHz authorized bandwidth), or 1900 Hz the provisions of § 2.1400 in subpart M (for 4.0 kHz authorized bandwidth), the and § 73.644(c) of part 73 to a certifi- level of which is adjusted to produce a cated or formerly type accepted trans- radio frequency signal component

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equal in magnitude to the magnitude audio modulating circuit over a range of the carrier in this mode. of 100 to 5000 Hz shall be submitted. For (3) As an alternative to paragraphs equipment required to have an audio (b) (1) and (2) of this section other low-pass filter, a curve showing the fre- tones besides those specified may be quency response of the filter, or of all used as modulating frequencies, upon a circuitry installed between the modu- sufficient showing of need. However, lation limiter and the modulated stage any tones so chosen must not be har- shall be submitted. monically related, the third and fifth (b) Equipment which employs modula- order products which tion limiting. A curve or family of occur must fall within the ¥25 dB step curves showing the percentage of mod- of the emission bandwidth limitation ulation versus the input curve, the seventh and ninth order voltage shall be supplied. The informa- intermodulation product must fall tion submitted shall be sufficient to within the 35 dB step of the referenced show modulation limiting capability curve and the eleventh and all higher throughout the range of modulating order products must fall beyond the frequencies and input modulating sig- ¥35 dB step of the referenced curve. nal levels employed. (4) Independent sideband transmit- (c) Single sideband and independent ters having two channels by 1700 Hz sideband radiotelephone transmitters tones applied simultaneously in both which employ a device or circuit to limit channels, the input levels of the tones peak envelope power. A curve showing so adjusted that the two principal fre- the peak envelope power output versus quency components of the radio fre- the modulation input voltage shall be quency signal produced are equal in supplied. The modulating signals shall magnitude. be the same in frequency as specified in (5) Independent sideband transmit- paragraph (c) of § 2.1049 for the occupied ters having more than two channels by bandwidth tests. an appropriate signal or signals applied (d) Other types of equipment. A curve to all channels simultaneously. The or equivalent data which shows that input signal or signals shall simulate the equipment will meet the modula- the input signals specified by the man- tion requirements of the rules under ufacturer for normal operation. which the equipment is to be licensed. (6) Single-channel controlled-carrier transmitters in the A3 emission mode— [39 FR 5919, Feb. 15, 1974. Redesignated and by a 2500 Hz tone. amended at 63 FR 36599, July 7, 1998] (c) For measurements conducted pur- suant to paragraphs (a) and (b) of this § 2.1049 Measurements required: Occu- section, all calculations and methods pied bandwidth. used by the applicant for determining The occupied bandwidth, that is the carrier power or peak envelope power, frequency bandwidth such that, below as appropriate, on the basis of meas- its lower and above its upper frequency ured power in the radio frequency load limits, the mean powers radiated are attached to the transmitter output ter- each equal to 0.5 percent of the total minals shall be shown. Under the test mean power radiated by a given emis- conditions specified, no components of sion shall be measured under the fol- the emission spectrum shall exceed the lowing conditions as applicable: limits specified in the applicable rule (a) Radiotelegraph transmitters for parts as necessary for meeting occu- manual operation when keyed at 16 pied bandwidth or emission limita- dots per second. tions. (b) Other keyed transmitters—when [39 FR 5919, Feb. 15, 1974. Redesignated and keyed at the maximum machine speed. amended at 63 FR 36599, July 7, 1998] (c) Radiotelephone transmitters equipped with a device to limit modu- § 2.1047 Measurements required: Mod- lation or peak envelope power shall be ulation characteristics. modulated as follows. For single side- (a) Voice modulated communication band and independent sideband trans- equipment. A curve or equivalent data mitters, the input level of the modu- showing the frequency response of the lating signal shall be 10 dB greater

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