- § 74.501 - Classes of aural broadcast auxiliary stations.
- § 74.502 - Frequency assignment.
- § 74.503 - Frequency selection.
- § 74.531 - Permissible service.
- § 74.532 - Licensing requirements.
- § 74.533 - Remote control and unattended operation.
- § 74.534 - Power limitations.
- § 74.535 - Emission and bandwidth.
- § 74.536 - Directional antenna required.
- § 74.537 - Temporary authorizations.
- § 74.550 - Equipment authorization.
- § 74.551 - Equipment changes.
- § 74.561 - Frequency tolerance.
- § 74.562 - Frequency monitors and measurements.
- § 74.582 - Station identification.
§ 74.501 - Classes of aural broadcast auxiliary stations.
(a) Aural broadcast STL station. A fixed station for the transmission of aural program material between the studio and the transmitter of a broadcasting station other than an international broadcasting station.
(b) Aural broadcast intercity relay (ICR) station. A fixed station for the transmission of aural program material between radio broadcast stations, other than international broadcast stations, between FM radio broadcast stations and their co-owned FM booster stations, between noncommercial educational FM radio stations and their co-owned noncommercial educational FM translator stations assigned to reserved channels (Channels 201 to 220), between FM radio stations and FM translator stations operating within the coverage contour of their primary stations, or for such other purposes as authorized in § 74.531.
(c) Aural broadcast microwave booster station. A fixed station in the broadcast auxiliary service that receives and amplifies signals of an aural broadcast STL or intercity relay station and retransmits them on the same frequency.
§ 74.502 - Frequency assignment.
(a) Except as provided in NG30, broadcast auxiliary stations licensed as of November 21, 1984, to operate in the band 942-944 MHz
(b) The frequency band 944-952 MHz is available for assignment to aural STL and ICR stations. One or more of the following 25 kHz segments may be stacked to form a channel which may be assigned with a maximum authorized bandwidth of 300 kHz except as noted in the following Table. The channel, will be assigned by its center frequency, channel bandwidth, and emission designator. The following frequencies are the centers of individual segments. When stacking an even number of segments, the center frequency specified will deviate from the following frequencies in that it should correspond to the actual center of stacked channels. When stacking an odd number of channels, the center frequency specified will correspond to one of the following frequencies.944.0125, 944.0375, 944.0625, 944.0875, 944.1125, 944.1375, 944.1625, 944.1875, 944.2125, 944.2375, 944.2625, 944.2875, 944.3125, 944.3375, 944.3625, 944.3875, 944.4125, 944.4375, 944.4625, 944.4875, 944.5125, 944.5375, 944.5625, 944.5875, 944.6125, 944.6375, 944.6625, 944.6875, 944.7125, 944.7375, 944.7625, 944.7875, 944.8125, 944.8375, 944.8625, 944.8875, 944.9125, 944.9375, 944.9625, 944.9875, 945.0125, 945.0375, 945.0625, 945.0875, 945.1125, 945.1375, 945.1625, 945.1875, 945.2125, 945.2375, 945.2625, 945.2875, 945.3125, 945.3375, 945.3625, 945.3875, 945.4125, 945.4375, 945.4625, 945.4875, 945.5125, 945.5375, 945.5625, 945.5875, 945.6125, 945.6375, 945.6625, 945.6875, 945.7125, 945.7375, 945.7625, 945.7875, 945.8125, 945.8375, 945.8625, 945.8875, 945.9125, 945.9375, 945.9625, 945.9875, 946.0125, 946.0375, 946.0625, 946.0875, 946.1125, 946.1375, 946.1625, 946.1875, 946.2125, 946.2375, 946.2625, 946.2875, 946.3125, 946.3375, 946.3625, 946.3875, 946.4125, 946.4375, 946.4625, 946.4875, 946.5125, 946.5375, 946.5625, 946.5875, 946.6125, 946.6375, 946.6625, 946.6875, 946.7125, 946.7375, 946.7625, 946.7875, 946.8125, 946.8375, 946.8625, 946.8875, 946.9125, 946.9375, 946.9625, 946.9875, 947.0125, 947.0375, 947.0625, 947.0875, 947.1125, 947.1375, 947.1625, 947.1875, 947.2125, 947.2375, 947.2625, 947.2875, 947.3125, 947.3375, 947.3625, 947.3875, 947.4125, 947.4375, 947.4625, 947.4875, 947.5125, 947.5375, 947.5625, 947.5875, 947.6125, 947.6375, 947.6625, 947.6875, 947.7125, 947.7375, 947.7625, 947.7875, 947.8125, 947.8375, 947.8625, 947.8875, 947.9125, 947.9375, 947.9625, 947.9875, 948.0125, 948.0375, 948.0625, 948.0875, 948.1125, 948.1375, 948.1625, 948.1875, 948.2125, 948.2375, 948.2625, 948.2875, 948.3125, 948.3375, 948.3625, 948.3875, 948.4125, 948.4375, 948.4625, 948.4875, 948.5125, 948.5375, 948.5625, 948.5875, 948.6125, 948.6375, 948.6625, 948.6875, 948.7125, 948.7375, 948.7625, 948.7875, 948.8125, 948.8375, 948.8625, 948.8875, 948.9125, 948.9375, 948.9625, 948.9875, 949.0125, 949.0375, 949.0625, 949.0875, 949.1125, 949.1375, 949.1625, 949.1875, 949.2125, 949.2375, 949.2625, 949.2875, 949.3125, 949.3375, 949.3625, 949.3875, 949.4125, 949.4375, 949.4625, 949.4875, 949.5125, 949.5375, 949.5625, 949.5875, 949.6125, 949.6375, 949.6625, 949.6875, 949.7125, 949.7375, 949.7625, 949.7875, 949.8125, 949.8375, 949.8625, 949.8875, 949.9125, 949.9375, 949.9625, 949.9875, 950.0125, 950.0375, 950.0625, 950.0875, 950.1125, 950.1375, 950.1625, 950.1875, 950.2125, 950.2375, 950.2625, 950.2875, 950.3125, 950.3375, 950.3625, 950.3875, 950.4125, 950.4375, 950.4625, 950.4875, 950.5125, 950.5375, 950.5625, 950.5875, 950.6125, 950.6375, 950.6625, 950.6875, 950.7125, 950.7375, 950.7625, 950.7875, 950.8125, 950.8375, 950.8625, 950.8875, 950.9125, 950.9375, 950.9625, 950.9875, 951.0125, 951.0375, 951.0625, 951.0875, 951.1125, 951.1375, 951.1625, 951.1875, 951.2125, 951.2375, 951.2625, 951.2875, 951.3125, 951.3375, 951.3625, 951.3875, 951.4125, 951.4375, 951.4625, 951.4875, 951.5125, 951.5375, 951.5625, 951.5875, 951.6125, 951.6375, 951.6625, 951.6875, 951.7125, 951.7375, 951.7625, 951.7875, 951.8125, 951.8375, 951.8625, 951.8875, 951.9125, 951.9375, 951.9625, 951.9875.
(1) A single broadcast station may be authorized up to a maximum of twenty segments (500 kHz total bandwidth) for transmission of program material between a single origin and one or more designations. The station may lease excess capacity for broadcast and other uses on a secondary basis, subject to availability of spectrum for broadcast use. However, an FM station licensed for twelve or fewer segments (300 kHz total bandwidth) or an AM station licensed for eight or fewer segments (200 kHz total bandwidth) may lease excess capacity for broadcast and other uses on a primary basis.
(2) An applicant (new or modification of existing license) may assume the cost of replacement of one or more existing licensees equipment with narrowband equipment of comparable capabilities and quality in order to make available spectrum for its facilities. Existing licensees must accept such replacement without cost to them except upon a showing that the replacement equipment does not meet the capability or quality requirements.
(c) Aural broadcast STL and intercity relay stations that were licensed or had applications pending before the Commission as of September 18, 1998 may continue those operations in the band 18,760-18,820 and 19,100-19,160 MHz on a shared co-primary basis with other services under parts 21, 25, and 101 of this chapter until June 8, 2010. Prior to June 8, 2010, such stations are subject to relocation by licensees in the fixed-satellite service. Such relocation is subject to the provisions of §§ 101.85 through 101.97 of this chapter. After June 8, 2010, such operations are not entitled to protection from fixed-satellite service operations and must not cause unacceptable interference to fixed-satellite service station operations. No applications for new licenses will be accepted in these bands after June 8, 2000.
(1)(i) 5 MHz maximum authorized bandwidth channels:
|Transmit (receive) (MHz)||Receive
(ii) Licensees may use either a two-way link or one frequency of a frequency pair for a one-way link.
(d) For the coordination of all frequency assignments for fixed stations above 944 MHz, for each frequency authorized under this part, the interference protection criteria in § 101.105(a), (b), and (c) of this chapter and the frequency usage coordination procedures of § 101.103(d) of this chapter will apply.
(e) The use of the frequencies listed in paragraph (b) of this section by aural broadcast intercity relay stations is subject to the condition that no harmful interference is caused to other classes of stations operating in accordance with the Table of Frequency Allocations contained in § 2.106 of this chapter.
§ 74.503 - Frequency selection.
(a) Each application for a new station or change in an existing station shall be specific with regard to frequency. In general, the lowest suitable frequency will be assigned which, on an engineering basis, will not cause harmful interference to other stations operating in accordance with existing frequency allocations.
(b) Where it appears that interference may result from the operation of a new station or a change in the facilities of an existing station, the Commission may require a showing that harmful interference will not be caused to existing stations or that if interference will be caused the need for the proposed service outweighs the loss of service due to the interference.
§ 74.531 - Permissible service.
(a) An aural broadcast STL station is authorized to transmit aural program material between the studio and transmitter location of a broadcasting station, except an international broadcasting station, for simultaneous or delayed broadcast.
(b) An aural broadcast intercity relay station is authorized to transmit aural program material between broadcasting stations, except international broadcasting stations, for simultaneous or delayed broadcast.
(c) An aural broadcast intercity relay station is authorized to transmit aural program material between noncommercial educational FM radio stations and their co-owned noncommercial educational FM translator stations assigned to reserved channels (Channels 201 to 220) and between FM radio stations and FM translator stations operating within the coverage contour of their primary stations. This use shall not interfere with or otherwise preclude use of these broadcast auxiliary facilities by broadcast auxiliary stations transmitting aural programming between broadcast stations as provided in paragraph (b) of this section.
(d) An aural broadcast STL or intercity relay may be used to transmit material between an FM broadcast radio station and an FM booster station owned, operated, and controlled by the licensee of the originating FM radio station. This use shall not interfere with or otherwise preclude use of these broadcast auxiliary facilities by broadcast auxiliary stations transmitting aural programming between the studio and transmitter location of a broadcast station or between broadcast stations as provided in paragraphs (a) and (b) of this section.
(e) An aural broadcast microwave booster station is authorized to retransmit the signals of an aural broadcast STL or intercity relay station.
(f) Multiplexing of the STL or intercity relay transmitter may be employed to provide additional communication channels for the transmission of aural program material, news-wire teleprinter signals relaying news to be associated with main channel programming, operational communications, and material authorized to be transmitted over an FM station under a valid Subsidiary Communications Authorization (SCA). An aural broadcast STL or intercity relay station may not be operated solely for the transmission of operational, teleprinter or subsidiary communications. Operational communications include cues, orders, and other communications directly related to the operation of the broadcast station as well as special signals used for telemetry or the control of apparatus used in conjunction with the broadcasting operations.
(g) All program material, including subsidiary communications, transmitted over an aural broadcast STL or intercity relay station shall be intended for use by broadcast stations owned or under common control of the licensee or licensees of the STL or intercity relay station. Other broadcast stations may simultaneously utilize such program material with permission of the STL or intercity relay station licensee.
(h) In any case where multiplexing, is employed on an aural broadcast STL station for the simultaneous transmission of more than one aural channel, the STL transmitter must be capable of transmitting the multiple channels within the channel on which the STL station is authorized to operate and with adequate technical quality so that each broadcast station utilizing the circuit can meet the technical performance standards stipulated in the rules governing that class of broadcasting station. If multiplex operation is employed during the regular operation of the STL station, the additional circuits shall be in operation at the time that the required periodic performance measurements are made of the overall broadcasting system from the studio microphone input circuit to the broadcast transmitter output circuit.
§ 74.532 - Licensing requirements.
(a) An aural broadcast STL or an aural broadcast intercity relay station will be licensed only to the licensee or licensees of broadcast stations, including low power FM stations, other than international broadcast stations, and for use with broadcast stations owned entirely by or under common control of the licensee or licensees. An aural broadcast intercity relay station also will be licensed for use by low power FM stations, noncommercial educational FM translator stations assigned to reserved channels (Channels 201-220) and owned and operated by their primary station, by FM translator stations operating within the coverage contour of their primary stations, and by FM booster stations. Aural auxiliary stations licensed to low power FM stations will be assigned on a secondary basis; i.e., subject to the condition that no harmful interference is caused to other aural auxiliary stations assigned to radio broadcast stations. Auxiliary stations licensed to low power FM stations must accept any interference caused by stations having primary use of aural auxiliary frequencies.
(b) More than one aural broadcast STL or intercity relay station may be licensed to a single licensee upon a satisfactory showing that the additional stations are needed to provide different program circuits to more than one broadcast station, to provide program circuits from other studios, or to provide one or more intermediate relay stations over a path which cannot be covered with a single station due to terrain or distance.
(c) If more than one broadcast station or class of broadcast station is to be served by a single aural broadcast auxiliary station, this information must be stated in the application for construction permit or license.
(d) Licensees of aural broadcast STL and intercity relay stations may be authorized to operate one or more aural broadcast microwave booster stations for the purpose of relaying signals over a path that cannot be covered with a single station.
(e) Each aural broadcast auxiliary station will be licensed at a specified transmitter location to communicate with a specified receiving location, and the direction of the main radiation lobe of the transmitting antenna will be a term of the station authorization.
(f) In case of permanent discontinuance of operations of a station licensed under this subpart, the licensee shall cancel the station license using FCC Form 601. For purposes of this section, a station which is not operated for a period of one year is considered to have been permanently discontinued.
§ 74.533 - Remote control and unattended operation.
(a) Aural broadcast STL and intercity relay stations may be operated by remote control provided that such operation is conducted in accordance with the conditions listed below:
(1) The remote control system must provide adequate monitoring and control functions to permit proper operation of the station.
(2) The remote control system must be designed, installed, and protected so that the transmitter can only be activated or controlled by persons authorized by the licensee.
(3) The remote control system must prevent inadvertent transmitter operation due to malfunctions in circuits between the control point and transmitter.
(b) Aural broadcast auxiliary stations may be operated unattended subject to the following provisions:
(1) The transmitter shall be provided with adequate safeguards to prevent improper operation of the equipment.
(2) The transmitter installation shall be adequately protected against tampering by unauthorized persons.
(3) Whenever an unattended aural broadcast auxiliary station is used, appropriate observations must be made at the receiving end of the circuit as often as necessary to ensure proper station operation. However, an aural broadcast STL (and any aural broadcast microwave booster station) associated with a radio or TV broadcast station operated by remote control may be observed by monitoring the broadcast station's transmitted signal at the remote control or ATS monitoring point.
(c) The FCC may notify the licensee to cease or modify operation in the case of frequency usage disputes, interference or similar situations where such action appears to be in the public interest, convenience and necessity.
§ 74.534 - Power limitations.
(a) Transmitter output power. (1) Transmitter output power shall be limited to that necessary to accomplish the function of the system.
(2) In the 17,700 to 19,700 MHz band, transmitter output power shall not exceed 10 watts.
(b) In no event shall the average equivalent isotropically radiated power (EIRP), as referenced to an isotropic radiator, exceed the values specified in the following table. In cases of harmful interference, the Commission may, after notice and opportunity for hearing, order a change in the equivalent isotropically radiated power of this station.
|Frequency band (MHz)||Maximum Allowable 1 EIRP (dBW)||944 to 952||+ 40||17,700 to 18,600||+ 55||18,600 to 19,700||+ 35|
1 Stations licensed based on an application filed before April 16, 2003, for EIRP values exceeding those specified above, may continue to operate indefinitely in accordance with the terms of their current authorizations, subject to periodic renewal.
(c) The EIRP of transmitters that use Automatic Transmitter Power Control (ATPC) shall not exceed the EIRP specified on the station authorization. The EIRP of non-ATPC transmitters shall be maintained as near as practicable to the EIRP specified on the station authorization.
§ 74.535 - Emission and bandwidth.
(a) The mean power of emissions shall be attenuated below the mean transmitter power (P
(1) When using frequency modulation:
(i) On any frequency removed from the assigned (center) frequency by more than 50% up to and including 100% of the authorized bandwidth: At least 25 dB in any 100 kHz reference bandwidth (B
(ii) On any frequency removed from the assigned (center) frequency by more than 100% up to and including 250% of the authorized bandwidth: At least 35 dB in any 100 kHz reference bandwidth;
(iii) On any frequency removed from the assigned (center) frequency by more than 250% of the authorized bandwidth: At least 43 + 10 log
(2) When using transmissions employing digital modulation techniques:
(i) For operating frequencies below 15 GHz, in any 4 kHz reference bandwidth (B
(ii) For operating frequencies above 15 GHz, in any 1 MHz reference bandwidth (B
(iii) In any 4 kHz reference bandwidth (B
(b) For all emissions not covered in paragraph (a) of this section, the peak power of emissions shall be attenuated below the peak envelope transmitter power (P
(1) On any frequency 500 Hz inside the channel edge up to and including 2500 Hz outside the same edge, the following formula will apply:A = 29 Log
(2) On any frequency removed from the channel edge by more than 2500 Hz: At least 43 + 10 Log
(c) In the event a station's emissions outside its authorized channel cause harmful interference, the Commission may require the licensee to take such further steps as may be necessary to eliminate the interference.
(d) For purposes of compliance with the emission limitation requirements of this section:
(1) If the transmitter modulates a single carrier, digital modulation techniques are considered as being employed when digital modulation occupies 50 percent or more of the total peak frequency deviation of a transmitted radio frequency carrier. The total peak frequency deviation will be determined by adding the deviation produced by the digital modulation signal and the deviation produced by any frequency division multiplex (FDM) modulation used. The deviation (D) produced by the FDM signal must be determined in accordance with § 2.202(f) of this chapter.
(2) If the transmitter modulates two or more carriers, with at least one using digital modulation and one using frequency or other analog modulation, digital modulation techniques are considered as being employed when the necessary bandwidth of the digital signal(s) is 50 percent or more of the aggregate bandwidth of the system, comprising the digital necessary bandwidth(s), the analog necessary bandwidth(s), and any bandwidth(s) between the digital and analog necessary bandwidths. In this case, the aggregate bandwidth shall be used for the authorized bandwidth (B) in paragraph (a) of this section, and for purposes of compliance with the bandwidth limitations in § 74.502 of this subpart; and the sum of the powers of the analog and digital signals shall be used for mean transmitter power (P
(3) For demonstrating compliance with the attenuation requirements for frequency modulation and digital modulation in paragraph (a) of this section, the resolution bandwidth (B
(4) Stations licensed pursuant to an application filed before March 17, 2005, using equipment not conforming with the emission limitations specified above, may continue to operate indefinitely in accordance with the terms of their current authorizations, subject to periodic renewal. existing equipment and equipment of product lines in production before April 16, 2003, authorized via certification or Declaration of Conformity before March 17, 2005, for equipment not conforming to the emission limitations requirements specified above, may continue to be manufactured and/or marketed, but may not be authorized for use under a station license except at stations licensed pursuant to an application filed before March 17, 2005. Any non-conforming equipment authorized under a station license, and replaced on or after March 17, 2005, must be replaced by conforming equipment.Note 1 to paragraph (
the Declaration of Conformity procedure has been replaced by the Supplier's Declaration of Conformity procedure. See § 2.950 of this chapter.
(e) The following limitations apply to the operation of aural broadcast microwave booster stations:
(1) The booster station must receive and amplify the signals of the originating station and retransmit them on the same frequency without significantly altering them in any way. The characteristics of the booster transmitter output signal shall meet the requirements applicable to the signal of the originating station.
(2) The licensee is responsible for correcting any condition of interference that results from the radiation of radio frequency energy outside the assigned channel. Upon notice by the FCC to the station licensee that interference is being caused, operation of the apparatus must be immediately suspended and may not be resumed until the interference has been eliminated or it can be demonstrated that the interference is not due to spurious emissions. However, short term test transmissions may be made during the period of suspended operation to determine the efficacy of remedial measures.
(3) In each instance where suspension of operation is required, the licensee must submit a full report to the FCC after operation is resumed. The report must contain details of the nature of the interference, the source of interfering signals, and the remedial steps taken to eliminate the interference.
§ 74.536 - Directional antenna required.
(a) Aural broadcast STL and ICR stations are required to use a directional antenna with the minimum beamwidth necessary, consistent with good engineering practice, to establish the link.
(b) An aural broadcast STL or intercity relay station operating in the 17.7-19.7 GHz band shall employ an antenna that meets the performance standards for Category A, except that in areas not subject to frequency congestion, antennas meeting standards for Category B may be employed. However, the Commission may require the replacement, at the licensee's expense, of any antenna or periscope antenna system of a permanent fixed station that does not meet performance Standard A, which is specified in the table in paragraph (c) of this section, upon a showing that said antenna causes or is likely to cause interference to (or receive interference from) any other authorized or proposed station; provided that an antenna meeting performance Standard A is unlikely to involve such interference.
(c) Licensees shall comply with the antenna standards table shown in this paragraph in the following manner:
(1) With either the maximum beamwidth to 3 dB points requirement or with the minimum antenna gain requirement; and
(2) With the minimum radiation suppression to angle requirement.
|Frequency (GHz)||Category||Maximum beamwidth to 3 dB points
(included angle in
|Minimum antenna gain (dbi)||Minimum radiation suppression to angle in degrees from centerline of main beam in decibels||5° to 10°||10° to 15°||15° to 20°||20° to 30°||30° to 100°||100° to 140°||140° to 180°||17.7 to 19.7||A
1 If a licensee chooses to show compliance using maximum beamwidth to 3 dB points, the beamwidth limit shall apply in both the azimuth and the elevation planes.
§ 74.537 - Temporary authorizations.
(a) Special temporary authority may be granted for aural broadcast STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such authority will normally be granted only for operations of a temporary nature. Where operation is seen as likely on a continuing annual basis, an application for a regular authorization should be submitted.
(b) A request for special temporary authority for the operation of an aural broadcast STL or an intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter.
(c) All requests for special temporary authority of an aural broadcast auxiliary stations must include full particulars including: licensee's name and address, facility identification number of the associated broadcast station(s), call letters of the aural broadcast STL or intercity relay station, if assigned, type and manufacturer of equipment, effective isotropic radiated power, emission, frequency or frequencies proposed for use, commencement and termination date and location of the proposed operation, and purpose for which request is made including any particular justification.
(d) A request for special temporary authorization shall specify a frequency or frequencies consistent with the provisions of § 74.502. However, in the case of events of widespread interest and importance which cannot be transmitted successfully on these frequencies, frequencies assigned to other services may be requested upon a showing that operation thereon will not cause interference to established stations. In no case will operation of an aural broadcast STL or intercity relay station be authorized on frequencies employed for the safety of life or property.
(e) When the transmitting equipment utilized is not licensed to the user, the user shall nevertheless have full control over the use of the equipment during the period it is operated.
(f) Special temporary authorization to permit operation of aural broadcast STL or intercity relay stations or systems pending FCC action on an application for regular authority will normally not be granted.
§ 74.550 - Equipment authorization.
Each authorization for aural broadcast STL, ICR, and booster stations shall require the use of equipment which has received a grant of certification or authorized under a Supplier's Declaration of Conformity. Equipment which has not been approved under the equipment authorization program and which was in service prior to July 1, 1993, may be retained solely for temporary uses necessary to restore or maintain regular service provided by approved equipment, because the main or primary unit has failed or requires servicing. Such temporary uses may not interfere with or impede the establishment of other aural broadcast auxiliary links and may not occur during more than 720 cumulative hours per year. Should interference occur, the licensee must take all steps necessary to eliminate it, up to and including cessation of operation of the auxiliary transmitter. All unapproved equipment retained for temporary use must have been in the possession of the licensee prior to July 1, 1993, and may not be obtained from other sources. Equipment designed exclusively for fixed operation shall be authorized under Supplier's Declaration of Conformity procedure. The equipment authorization procedures are contained in subpart J of part 2 of this chapter.Note 1 to § 74.550:
The Declaration of Conformity procedure has been replaced by Supplier's Declaration of Conformity. Equipment previously authorized under subpart J of part 2 of this chapter may remain in use. See § 2.950 to this chapter.Note 2 to § 74.550:
Consistent with the note to § 74.502(a), grandfathered equipment in the 942-944 MHz band and STL/ICR users of these frequencies in Puerto Rico are also required to come into compliance by July 1, 1993. The backup provisions described above apply to these stations also.
§ 74.551 - Equipment changes.
(a) Modifications may be made to an existing authorization in accordance with §§ 1.929 and 1.947 of this chapter.
(b) Permissible changes in equipment operating in the bands 18.3-18.58, 18.76-18.82 GHz and 19.1-19.16 GHz. Notwithstanding other provisions of this section, licensees of stations that remain co-primary under the provisions of § 74.502(c) may not make modifications to their systems that increase interference to satellite earth stations, or result in a facility that would be more costly to relocate.
§ 74.561 - Frequency tolerance.
In the bands above 944 MHz, the operating frequency of the transmitter shall be maintained in accordance with the following table:
|Frequency band (MHz)||Tolerance as percentage of assigned frequency||944 to 952||0.005||17,700 to 19,700||0.003|
§ 74.562 - Frequency monitors and measurements.
The licensee shall ensure that the STL, ICR, TVP, or booster transmitter does not exceed the emission limitations of § 74.535. This may be accomplished by appropriate frequency measurement techniques and consideration of the transmitter emissions.
§ 74.582 - Station identification.
(a) Each aural broadcast STL or intercity relay station, when transmitting program material or information shall transmit station identification at the beginning and end of each period of operation, and hourly, as close to the hour as feasible, at a natural break in program offerings by one of the following means:
(1) Transmission of its own call sign by aural means or by automatic transmission of international Morse telegraphy.
(2) Aural transmission of the call sign of the radio broadcast station with which it is licensed as an STL or intercity relay station.
(3) Aural transmission of the call sign of the radio broadcast station whose signals are being relayed, or, when programs are obtained directly from network lines and relayed, the network identification.
(b) Station identification transmissions during operation need not be made when to make such transmission would interrupt a single consecutive speech, play, religious service, symphony concert, or other such productions. In such cases, the identification transmission shall be made at the first interruption of the entertainment continuity and at the conclusion thereof.
(c) Where more than one aural broadcast STL or intercity relay station is employed in an integrated relay system, the station at the point of origination may originate the transmission of the call signs of all of the stations in the relay system.
(d) Aural broadcast microwave booster stations will be assigned individual call signs. However, station identification will be accomplished by the retransmission of identification as provided in paragraph (a) of this section.
(e) Voice transmissions shall normally be employed for station identification. However, other methods of station identification may be permitted or required by the Commission.