Technical Standards for Broadcast Service Technical Unit 12/19/2013
Table of Contents 1. Introduction... 3 2. Scope 3 3. Acceptability of Equipment... 4 3.2. Equipment Labels... 4 3.3. Engineering Guidelines... 4 3.3.1. Access to Transmission Equipment:... 4 3.3.2. Metering and Monitoring:... 5 3.3.3. Environmental and Reliability Requirements:... 5 4. Sound Broadcasting Systems using Amplitude Modulation... 5 4.1. Technical Standards for Signal Transmission and Reception.... 5 4.2. AM Broadcast Channel... 5 4.3. Types of AM Stations... 5 4.4. Minimum Antenna Height... 6 4.5. Ground System... 6 5. Sound Broadcasting System Using Frequency Modulation... 7 5.1. Technical Standards for Signal Transmission and Reception... 7 5.2. Transmission System Standard... 7 5.3. Minimum Distance Separation Between Transmitters... 7 5.4. Transmitter Location... 8 5.5. Channels... 8 5.6. Type of Emissions... 8 5.7. Limits of Modulation... 8 5.8. Carrier Frequency Adjustment... 8 5.9. Phase to Phase Loading... 9 5.10. RF Carrier Performance Rating... 9 5.10.1. Power Output rating... 9 5.10.2. Carrier Frequency Stability... 9 5.10.3. Spurious Emissions... 9 5.10.4. Cabinet Radiation... 10 5.11. FM STEREOPHONIC SOUND TRANSMISSION STANDARD... 10 5.12. Radio Broadcast Data System... 12 Page 1 of 26
5.12.1. Modulation of the Data Channel... 12 5.13. Studio to Transmitter Links (STL)... 12 6. Community Radio Service... 14 6.1. General Considerations... 14 7. Technical Standards for Conventional Analogue Television Broadcast Transmission and Reception 14 7.1. National Television System Committee (NTSC)... 14 7.1.2. Standards... 15 7.1.3. Summary of Technical Details... 16 7.1.4. Channel Assignment:... 16 8. Technical Standards for Subscriber Television Signal Transmission and Reception... 17 8.1. Standards... 17 8.2. Prohibited Frequencies... 17 8.3. Technical Parameters for Transmission via Cable... 18 8.3.2. Frequency Separation Standards... 21 8.4. Channel Allocation Plan For Subscriber Television... 23 Glossary 26 References 26 Page 2 of 26
1. Introduction 1.1. This Technical Standards for Broadcasting Service have been developed under the authority of The National Telecommunications Regulatory Commission (The Commission) and represents a compilation of the minimum technical standards for the transmission and reception of signals within specified broadcast services. 1.2. Under the Telecommunications Act [No. 27 of 2000], broadcasting is defined as the "transmission of radio or video programming to the public on a free, pay, subscription, or other basis, whether by cable television, terrestrial, or satellite means, or by other electronic delivery of such programming. The broadcasting service comprises transmissions that are generally intended to be received directly by the public. Broadcast transmissions generally consist of sound or vision programmed signals, however broadcasters may embed control signals for network control and maintenance within the transmissions. As articulated in Article 23 of the ITU Radio Regulations, the establishment and use of broadcasting stations (sound broadcasting and television broadcasting stations) on board ships, aircraft or any other floating or airborne objects outside national territories is prohibited. 1.3. The regulatory treatment of the broadcast service required under the Telecommunications Act, is specific to the technical aspects of the network and the Commission is precluded from regulating programme content or scheduling. Persons engaged or desirous of operating a broadcast network must be licensed to do so. The broadcasting networks licence is the license required for broadcast operations and has been classified as a class license and authorizes persons to engage in the transmission of signals. 2. Scope 2.1. These standards define the minimum technical requirements for transmitting equipment/systems to be used in the broadcasting services for transmission and reception of signals. 2.2. Broadcasting Services include both analogue and digital technologies as both cable and radio frequency spectrum medium. These standards are directed specifically to AM Broadcasting Service, VHF Sound Broadcasting using FM, Conventional Analogue Television Broadcasting, and Subscriber Television service. These standards are industry standards applicable to equipment which are operating or intended for use in Saint Lucia. 2.3. The standards specifies among other things: a) The acceptability of equipment; b) Engineering guidelines; and c) The technical parameters of the transmission aspects of broadcast networks. Page 3 of 26
2.4. In the event of any inconsistencies between this document and the Telecommunications Act or its Regulations, the provisions stipulated in the Act or applicable Regulations shall take precedence. 3. Acceptability of Equipment 3.1. Equipment intended for use in the broadcast service must be granted Type Approval certification by the Commission, in lieu of this, relevant test results to indicate adherence to Radio Standards Specifications (RSS) and Interference Causing Equipment Standard (ICES). The Commission reserves the right to require adjustments to be made to the equipment should it cause interference notwithstanding having been prior certification. Any significant change made to the design, circuitry or operation of the equipment, other than for the replacement/repair of defective parts, will void the certification unless notice is provided to the Commission and approval is granted by the Commission. 3.2. Equipment Labels 3.2.1. All broadcasting equipment with Type Approval certification must be permanently labeled. The label must contain the following: a) The manufacturer's name or brand name; b) The model identification; c) The serial number; and d) The Type Approval Reference identification. In lieu of Type Approval identification the relevant specification tests (approved by the NTRC) should be used. 3.2.2. The identification label must be affixed permanently so that the above information can be seen throughout the operational life of the equipment. 3.3. Engineering Guidelines 3.3.1. Access to Transmission Equipment: All appropriate precautions should be enacted to prevent unauthorized access to any controls and adjustments which, if accessed, might result in noncompliance with the technical operational terms/standards specified in the Licence. Depending on the transmitter housing facility and its vulnerability, the broadcaster may have to enact certain measures such as: control of entry unto the premise; physical protection of adjustments; need for and control of specialist tools to make adjustments; etc. Page 4 of 26
3.3.2. Metering and Monitoring: The transmission equipment must incorporate a suitable meter indicating, or uniquely related to the RF output power. Regular (annually) checks and monitoring will be conducted by the NTRC of the transmission equipment/system. 3.3.3. Environmental and Reliability Requirements: Compliance with the equipment manufactures recommendations for the operational temperature range and relative humidity should be adhered to. The broadcaster may be required to put in the necessary air conditioning and temperature regulation system to ensure proper functioning of the equipment/systems. The broadcast should apply sound engineering practice throughout, including that: I. The transmission equipment/system should be designed such that it will not suffer damage when operated continuously especially in the case of Radio Frequency transmitters. II. Precautions should be taken to prevent switching or commutation spikes from being radiated or superimposed upon the incoming supply. III. Sufficient space should be provided adjacent to transmission equipment for location of the test equipment required to monitor and measure the parameters of transmission. 4. Sound Broadcasting Systems using Amplitude Modulation 4.1. Technical Standards for Signal Transmission and Reception. The standards contained in this chapter are the conditions necessary for the establishment of sound broadcasting in the Medium Wave (AM) band. 4.2. AM Broadcast Channel The band of frequencies occupied by the carrier and the upper and lower sidebands of an AM broadcast signal with the carrier frequency at the center. Channels are designated by their assigned carrier frequencies. The 117 carrier frequencies assigned to AM broadcast stations begin at 540 khz and progress in 10 khz steps to 1700 khz. 4.3. Types of AM Stations Generally there are recognized four classes of AM broadcast stations: 1) Class A 2) Class B 3) Class C and Page 5 of 26
4) Class D 4.3.1. A Class A station is an unlimited time station (that is, it can broadcast 24 hours per day) that operates on a clear channel. The operating power shall not be less than 10 kilowatts (kw) or more than 50 kw. 4.3.2. Class B.station is an unlimited time station. Class B stations are authorized to operate with a minimum power of 0.250 kw (250 watts) and maximum power of 50 kw. (If a Class B station operates with less than 0.250 kw, the RMS must be equal to or greater than 141 mv/m at 1 km for the actual power.) If the station is authorized to operate in the expanded band (1610 to 1700 khz), the maximum power is 10 kw. 4.3.3. A Class C.station is an unlimited time station that operates on a local channel. The power shall not be less than 0.25 kw or more than 1 kw. Class C stations that are licensed to operate with 0.100 kw may continue to operate as licensed. 4.3.4. A Class D.station operates either daytime, limited time, or unlimited time with a night time power less than 0.250 kw and an equivalent R.MS antenna field less than 141 mv/m at 1 km for the actual power. Class D stations shall operate with daytime powers not less than 0.250 kw or more than 50 kw. NOTE: If a station is an existing daytime-only station, its class will be Class D. 4.4. Minimum Antenna Height 4.4.1. For stations providing primary service the minimum antenna height must ensure a field strength of2r2mv/m@ 1km for 1KW station. 4.4.2. Ground wave signal strength required to provide primary service shall be maintained at 2 mv /m for communities with population greater than 2500 persons. For population less than 2500 persons, the signal strength shall be maintained at a level of 0.5mV/m or less. 4.5. Ground System 4.5.1. Ground system shall consist of buried radial wires at least a quarter of wavelength in length evenly spaced and should be not be less than 90 but ideally 120 at 0.35 of a wavelength to 0.4 of a wavelength in length. Page 6 of 26
5. Sound Broadcasting System Using Frequency Modulation 5.1. Technical Standards for Signal Transmission and Reception 5.1.1. Sound Broadcast System utilizing Frequency Modulation (FM) is a transmission technology that uses the technique of frequency modulation to emit audio signals (in most cases stereo) within the VHF band. 5.1.2. The standards contained in this chapter are the conditions necessary for the establishment of sound broadcasting using FM and relates to the transmission parameters of transmitters as well as the necessary levels of signal reception. 5.2. Transmission System Standard 5.2.1. Broadcasting equipment utilizing FM consist of all the apparatus necessary to convert the modulating input signal to a frequency modulated carrier at the center frequency of a standard channel in the frequency range 88 MHz to 108 MHz 5.2.2. Transmitters will be authorized for power levels which will provide the minimum accepted field strength of 70 dbµv/m or 3.16 mv/m but shall not exceed 500W transmitter power 1 and an ERP of 30dBW(1 kw). 5.2.3. The transmitter should not be linked directly to the antenna system, it is highly recommended that the transmitter or the output stage of the transmitters be equipped with a filtering device. 5.3. Minimum Distance Separation Between Transmitters 5.3.1. Table 5.3 demonstrates the minimum distance of separation for transmitters of VHF Sound Broadcasting Service using FM. Channel Separation Between Transmitters/kHz Minimum Distance for Separation/km 0 40 200 27 400 13 600 <13 Table 5.3 Illustrating minimum distance between FM transmitters 1 Community Radio Broadcast is limited to 25W. Page 7 of 26
5.4. Transmitter Location 5.4.1. The Location of the transmitter must be so chosen that on the basis of the effective radiated power and antenna height above average terrain (HAAT) employed, a minimum of 70 db above 1 µv/m (dbµ) or 3.16mV/m is provided over the service area. The transmitter location must ensure that the 1mV/m contour encompasses the population center that is being served. Also the co-location of broadcast transmitters and aeronautical radio communications equipment operating in the VHF range is strongly discouraged. 5.5. Channels 5.5.1. The transmitter shall operate within the range 88 MHz to 108 MHz, however note that the frequency range 88.1 MHz to 89.5 MHz is reserved for Community Radio Broadcast service. The recognized operating channels or frequencies shall be of channel separation of 200 khz. In Saint Lucia the sub bands channel assignments are recognized as the odd multiple assignments, i.e. 96.1 MHz, 96.3 MHz, 96.5 MHz, etc. 5.6. Type of Emissions 5.6.1. The designation of modulation and emission refer to the manner in which the carrier is modulated and transmitted. The transmitting equipment shall produce F3EGN emission for monophonic operation and F8EHF emission for stereophonic operation. The transmitting equipment shall be capable of operating with a frequency deviation of± 75 khz, which is equivalent to 100% modulation. 5.7. Limits of Modulation 5.7.1. Emissions shall not exceed 100 percent modulation except for the following conditions: a) FM multiplex sub carrier using any modulation may operate if the multiplexed sub carrier and their sidebands are maintained within the range 20 khz to 99 khz. b) Total peak modulation may be increased 0.5% for each 1.0% sub carrier injection modulation. 5.8. Carrier Frequency Adjustment 5.8.1. The transmitting equipment shall be capable of operation in accordance with these standards on any channel in the specified carrier frequency range without change in construction other than changing frequency determining components. Page 8 of 26
5.9. Phase to Phase Loading 5.9.1. The transmitting equipment, if rated above 10kVA, shall present a balanced load to the AC mains such that the current in each phase shall be ± 10% of the average of all three currents. 5.10. RF Carrier Performance Rating The following technical parameters are adapted from ITU-R Recommendation ITU-R BS.4503 and the technical parameters of the FM Radio broadcast network licence. 5.10.1. Power Output rating 5.10.1.1. The standard rating of power output for the transmitting equipment shall be as specified by the individual manufacturer. The transmitting equipment shall be capable of being adjusted to deliver the power output when the AC input voltage varies by 5% from the rated value. 5.10.2. Carrier Frequency Stability 5.10.2.1. The frequency of the carrier shall remain within ± 1000 Hz of the mean test frequency. 5.10.3. Spurious Emissions 5.10.3.1. A spurious emission from any part of the installation other than the antenna and its transmission line shall not have an effect greater than would occur if the antenna system were supplied with the maximum permitted power at that spurious emission frequency. Spurious emissions of the transmitting equipment shall not exceed the values given in Table 5.10.3. Spurious Emissions Maximum Value Between 120 khz and 240kHz from the -25dB 2 carrier frequency. More than 240 khz and up to and -35dB 2 including 600 khz from the carrier frequency More than 600 khz from the carrier -(43 +10 logp)' or 80dB' frequency whichever is the stronger P= power in watts Table 5.10.3 illustrating maximum value of spurious emissions 2 Refers to the power level of the unmodulated carrier Page 9 of 26
5.10.4. Cabinet Radiation 5.10.4.1. Emissions at any frequency shall be at least 54 db below the calculated field strength reference level. 5.11. FM STEREOPHONIC SOUND TRANSMISSION STANDARD 5.11.1. A FM broadcast station shall not use 19kHz± 20Hz, except as the stereophonic pilot frequency in a transmission system meeting the following criteria: a) The modulating signal for the main channel consists of the Left and Right signals; b) The pilot sub-carrier at 19 khz ± 2Hz shall frequency modulate the main carrier between the limits of 8 and 10 percent; c) One stereophonic sub-carrier shall be the second harmonic of the pilot subcarrier (that is, 38 khz) and shall cross the time axis with a positive slope simultaneously with each crossing of the time axis by the pilot sub-carrier which are not precluded; d) Double sideband, suppressed carrier amplitude modulation of the stereophonic sub-carrier at 38 khz shall be used; e) The stereophonic sub-carrier at 38 KHz shall be suppressed to a level less than 1 %of the main carrier; f) The modulating signal for the required sub-carrier shall be equal to the difference of the left and right signal; g) The applicable modulating levels: I. when a signal exists in only one channel of a two channel (biphonic) sound transmission, modulation of the carrier by audio components shall not exceed 45%, and modulation of the carrier by the sum of the amplitude modulated subcarrier in the base band range of 23 khz to 53 khz shall not exceed 45%; II. III. when a signal exists in only one channel of a stereophonic sound transmission having more than one stereophonic sub-carrier in the base band, the modulation of the carrier by audio components within the audio base band range of 23 khz to 99 khz shall not exceed 53% a station not transmitting stereo with a method described above shall limit the main carrier deviation caused by any modulating signals to occupying the band 19 khz ± 20Hz to 125Hz. Page 10 of 26
5.11.2. All stations, regardless of the stereophonic transmission shall not exceed the maximum modulation limits of 100 % on peaks on frequency recurrence to 75 khz deviation. Stations providing subsidiary communications services using subcarrier standards concurrently with the broadcasting of stereophonic or monophonic programs may increase the peak modulation deviation as follows: a) the total peak modulation may be increased 0.5% for each percent subcarrier injection modulation; b) the modulation shall not exceed 110 per cent (82.5 khz peak deviation). 5.11.3. FM stations operating with transmitter power greater than 10 Watts are to maintain the operating power within 90% and 110% of that authorized. 5.11.4. Departure of the carrier or center frequency of an FM station with an authorized power greater than 10 Watts may not deviate more than 2000 Hz from the authorized carrier. 5.11.5. The audio frequency distortion including all harmonics up to 30 khz shall not exceed 1% in the range of frequencies from 50 Hz to 15 000 Hz. Figure 5.11: Illustrating FM Stereographic signal Page 11 of 26
5.12. Radio Broadcast Data System 5.12.1. Modulation of the Data Channel 5.12.1.1. Radio Broadcast Data System or, Radio Data System, is a communications protocol standard for transmitting small amounts of digital information using conventional FM Sound Broadcast techniques. The RBDS system enables the transmission of several types of information transmitted, including station identification, automatic or assisted tuning functions of an FM receiver, weather and traffic reports, time, track/artist information, etc. 5.12.1.2. The system uses a 57 khz subcarrier to carry data at 1187.5 bits per second (± 0.125 bit/s), locked in phase or in quadrature to the third harmonic of the 19 khz pilot tone. 5.12.1.3. Sub-carrier level: the recommended nominal deviation of the main FM carrier due to the modulated sub-carrier is ± 2 khz. The decoder should, however, be designed to work with sub-carder levels corresponding to between± 1 khz and± 7.5 khz deviation. 5.12.1.4. Method of modulation: the sub-carrier is amplitude-modulated by the shaped and biphase-coded data signal. The sub-carrier is suppressed (see Figs. la) to 1c)). 5.13. Studio to Transmitter Links (STL) 5.13.1. Under the terms of the FM broadcast licence, the use of VHF broadcast frequencies (88-108MHz) for the rebroadcast of programme is not permitted. The operators are encouraged to use a studio to transmitter link in the UHF band (335.4 MHz to 399.9 MHz). 5.13.2. A studio-transmitter link (or STL) emits an audio signal from the studio to the transmitter at another location which is usually placed at a high-site. STL is a point to point link and STL transmitters are restricted to 15W (erp) and the antenna must be directional. The channel spacing is restricted to 500 khz. Page 12 of 26
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6. Community Radio Service 6.1. General Considerations 6.1.1. By virtue that Community Radio Service is part of the Sound Broadcasting Service using FM, the technical characteristics are similar, the exceptions are specified below: I. Transmitters will be authorized for power levels which will provide the minimum accepted field strength of 70 dbµv/m (3.16mV/m) but shall not exceed 25W transmitter power and an ERP 10dBW. II. The channels for Community Radio Service arc restricted within the band 88.1MHz to 89.5MHz 7. Technical Standards for Conventional Analogue Television Broadcast Transmission and Reception 7.1. National Television System Committee (NTSC) 7.1.1. Conventional analogue television broadcast in Saint Lucia, utilize the National Television System Committee (NTSC) standard for transmission of audio and video signals. NTSC television channel as transmitted occupies a total bandwidth of 6MHz. A guard band, which does not carry any signals, occupies the lowest 250 khz of the channel to avoid interference between the video signal of one channel and the audio signals of the next channel down. The actual video signal, which is amplitude-modulated, is transmitted between 500 khz and 5.45 MHz above the lower bound of the channel. 'the video carrier is 1.25 MHz above the lower bound of the channel. Like most AM signals, the video carrier generates two sidebands, one above the carrier and one below. The sidebands are each 4.2 MHz wide. The entire upper sideband is transmitted, but only 750 khz of the lower sideband, known as a vestigial sideband, is transmitted. The color subcarrier, as noted above, is 3.579545 MHz above the video carrier, and is quadrature-amplitude-modulated with suppressed carrier. The highest 25 khz of each channel contains the audio signal, which is frequencymodulated. The main audio carrier is 4.5 MHz above the video carrier. Page 14 of 26
7.1.2. Standards Television standard Channel bandwidth Channel configuration Minimum signal level at TV input NTSC 6.0 MHz per channel Standard 4.5 MHz video/audio: audio 15-17 db below carrier 2 dbmv across 75-ohm termination at the channel input Minimum Carrier/Noise 30 dbc (below carrier) Visual carrier frequency 1.256 MHz above channel lower limit Permissible variation of visual carrier level Over 24 hours 12 db max Between two adjacent channels 3 db max between any two channels 12 db max Frequency response (each channel) + 2 db from 0.75 khz to 4kHz above visual carrier level Aural frequency deviation 25kHz Signal to inter-modulation ratio 45dBmin Radiation level < 15 uv/mat30 metres Line amplifier voltage 60Vac max Figure 7.1.2 Page 15 of 26
7.1.3. Summary of Technical Details 7.1.4. Channel Assignment: The following tables represent the channel assignment for NTSC television transmission. Page 16 of 26
8. Technical Standards for Subscriber Television Signal Transmission and Reception 8.1. Standards The provision of cable television service is carried out with the use of domestic television set as the standard video output device. The standards applied though similar parts must not be used interchangeably as the mode of delivery is distinctly different; one being a coaxial cable and the other a wireless (RF) signal. Television standard Channel bandwidth Channel configuration Minimum signal level at TV input NTSC 6.0 MHz per channel Standard 4.5 MHz video/audio: audio 15-17 db below carrier 2 dbmv across 75-ohm termination at the channel input Minimum Carrier/Noise 30 dbc (below carrier) Visual carrier frequency 1.256 MHz above channel lower limit Permissible variation of visual carrier level Over 24 hours 12 db max Between two adjacent channels 3 db max between any two channels 12 db max Frequency response (each channel) + 2 db from 0.75 khz to 4kHz above visual carrier level Aural frequency deviation 25kHz Signal to inter-modulation ratio 45dBmin Radiation level < 15 uv/mat30 metres Line amplifier voltage 60Vac max 8.2. Prohibited Frequencies 8.2.1. No subscriber television system may utilize a frequency at power levels equal to or exceeding 10 micro watts within 100 khz plus tolerance of the emergency aircraft locator frequency 121.5 MHz or within 50 khz plus tolerance of the distress signal frequencies 156.8 MHz and 243.0MHz. Page 17 of 26
8.3. Technical Parameters for Transmission via Cable 8.3.1. This Part applies to the performance of a subscriber television system as measured at any subscriber terminal with a matched impedance at the termination point or at the output of the modulation or processing equipment (generally the head-end) of the subscriber television and are applicable to each NTSC or similar video downstream subscriber television channel in the system. 1) The subscriber television channels delivered to the subscriber's terminal shall be capable of being received and displayed by TV broadcast receivers used for the offthe-air reception of TV broadcast signals. 2) Subscriber television systems shall- a) Transmit channels to subscriber premises equipment on frequencies in accordance with the channel allocation plan specified in section 8.5; b) Use the channel allocation plan for signals transmitted in the frequency range 54 MHz to 1002MHz. 3) The aural centre frequency of the aural carrier shall be 4.5 MHz ± 5 khz above the frequency of the visual carrier at the output of the modulating or processing equipment of a subscriber television system and at the subscriber terminal. 4) (1) The visual signal level across a terminating impedance which correctly matches the internal impedance of the subscriber system as viewed from the subscriber terminal shall- a) not be less than 1 millivolt across an internal impedance at 75 ohms (0dBmV); b) as measured at the end of a 30 metre cable drop that is connected to the subscriber tap, not be less than 1.41 millivolts across an internal impedance of75 ohms(+ 3 dbmv). (2) At other impedance (Z) values, the minimum visual signal level as viewed from the subscriber terminal, shalt be the square.jo.0133 x Z milivolts and, as measured at the end of 30 metre cable drop that is connected to the subscriber tap shall be 2 0.00662 x Z millivolts. Page 18 of 26
5) The visual signal level on each channel as measured at the end of 30 metre cable drop that is connected to the subscriber tap shalt not vary more than 8 db within any six month interval, and shall be maintained within a) 3 db of the visual signal level of -any visual carrier within a 6 MHz nominal frequency separation b) 10 db of the visual signal level on any other channel on a cable television system of up to 300 MHz of a cable distribution system upper frequency limit, with a 1 db increase for each additional 100 MHz of cable distribution system upper frequency limit (for example, 11 db for a system at 301-400MHz, etc); and c) a maximum level such that signal degradation due to overload in the subscriber's receiver or terminal does not occur. 6) (1) The root mean square voltage of the aural signal shall be maintained between 10 and 20 db below the associated visual signal level and shall be met at the subscriber terminal and at the output of the modulating and processing equipment (generally the head-end). (2) Subscriber terminal which use equipment which modulate and demodulate the signal (for example, base band converters), the root mean square voltage of the aural signal shall be maintained between 6.5 and 17 db below the associated visual level at the subscriber terminal. 7) (1) The amplitude characteristic shall be a range of 2 db from 0.75 MHz to 5.0 MHz above the lower boundary frequency of the cable television channel referenced to the average of the highest and lowest amplitudes within those frequency boundaries. (2) The amplitude characteristic may be measured after subscriber tap and before a converter which is provided and maintained by the licensee may be measured at the subscriber terminal. 8) The ratio of RF visual signal level to the system noise shall not be less than 40dB. 9) The ratio of visual signal level to the root mean square amplitude of any coherent disturbances (for example, intermodulation products, second and the third order Page 19 of 26
distortions or discrete frequency interfering signals not operating on proper offset assignments): a) shall not be less than 51 db for noncoherent channel subscriber television systems, when ensured with modulated carriers and time averaged; and b) which are frequency-coincident with the visual currier, shall not be less than 47 db for current channel subscriber system \'{hen measured with modulated carriers and time averaged. 10) The terminal isolation provided to each subscriber terminal a) shall not be less than 18 db in lieu of periodic testing, so however, that the licensee may use specifications provided by the manufacturer for the terminal isolation equipment to meet this standard, and b) shall be sufficient to prevent reflections caused by open circuited or short-circuited subscriber terminals from producing visual picture impairments at any other subscriber terminal. 11) (1) The peak-to peak variation in visual signal level caused by undesired low frequency disturbances (hum or repetitive transients) generated within the system, or by inadequate low frequency response, shall not exceed 3 percent of the visual signal level. (2) Measurements made on a single channel using a single unmodulated carrier may be used to demonstrate compliance with this parameter at each test location. 12) The following requirements apply to the performance of the subscriber television system as measured at the output of the modulating or processing equipment (generally the head-end) of the system: a) the chrominance luminance delay inequality (or chrome delay} which is the change in delay time of the chrominance component of the signal relative to the luminance component, shall be within 170 nanoseconds; b) the differential gain for the colour subcarrier of the television signal which is measured as the difference in amplitude between the largest and smallest segments of the chrominance signal divided by the largest, shall not exceed ± 20%; and c) the differential phase for the colour subcarrier of the television signal which is measured as the largest phase difference in degrees between Page 20 of 26
each segment of the chrominance signal and reference segment (the segment at the blanking level of 0 IRE) shall not exceed ±10 degrees. 13) Signal leakage from n subscriber television systems shall be limited as follows: 14) (1) For operation in the frequency bands 108-137 and 225-400 MHz the standards relating to Signaling Leakage Performance Criteria and Frequency Separation Standards are applicable to all subscriber television systems transmitting carriers or other signal components carried at an average power level equal to or greater than 10-4 watts across a 25 KHz bandwidth in any 160 microsecond period at any point in the cable distribution system in the frequency bands 108-137 and 225-400 MHz for any purpose. (2) Before transmitting any carrier or other signal component with an average power level across a 25 Hz bandwidth in any 160 microsecond time period ec1ual to or greater than 10-4 watts at any point in the subscriber television distribution system on any new frequency or frequencies the aeronautical radio frequency bands the licensee is to notify the Commission. 8.3.2. Frequency Separation Standards 8.3.2.1. All subscriber television systems which operate in the frequency bands 108-137 and 225-400 MHz shall comply with the following frequency separation standards: 1) In the aeronautical radio communication bands 108-137, 225-328.6 and 335.4-400 MHz, the frequency of all carrier signals or signal components carried at an average power level equal to or greater than 10-4 watts in a 25 khz bandwidth in any 160 microsecond period shall operate at frequencies offset from certain frequencies which may be used by aeronautical radio services and the aeronautical frequencies from which offsets shall be maintained are those frequencies which arc within one of the Page 21 of 26
aforementioned aeronautical bands, and when expressed in MHz and divide by 0.025 yield an integer, the offset meeting one of the following criteria; a) all such cable carriers or signal components shall be offset by 12.5kHz with a frequency tolerance of± 5 Hz; or b) the fundamental frequency from which the carrier frequencies arc derived by multiplication by an integer number which shall be 6.0003 MHz with a tolerance of± 1Hz Harmonically Related Carrier (HRC) comb generators only 2) In the aeronautical radio navigation bands 108-118 and 328.6-335.4 MHz, the frequency of all carrier signals or signal components carrier at an average power level equal to or greater than 10 4 watts in a 25Hz bandwidth in any 160 microsecond period shall be offset by 25 hz with a tolerance of ±5hz and the aeronautical radio-navigation frequencies from which offsets shall be maintained arc as follows- a) within the aeronautical band108-118 MHz when expressed in MHz and divided by 0.025 yield even integer; b) within the band328.6-335.4mhz. NOTE: The Harmonically Related Carrier (HRC) system shall meet the requirement in the 328.5-335.4 MHz navigation glide path band, those incrementally Related Carriers (IC) system with comb generator reference frequencies set at certain odd multiples equal to or greater than 3 times the 0.0125 MHz aeronautical communications band offset (for example 6n ± 1.250 ± 0.0375 MHz may also meet the 25 khz offset requirement in the navigation glide path band). Page 22 of 26
8.4. Channel Allocation Plan For Subscriber Television 8.4.1. No allocation shall be made by a licensee who operates subscriber television service for operations over the standard VHF Channels which are in use for conventional analogue television broadcasting operations in the zone served by the licensee, that is to say, channels 2 to 13. Page 23 of 26
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Glossary Cabinet Radiation: is any emission from the transmitting equipment housing or enclosure from sources other than a normal output port. Carrier Frequency Stability. is the ability of the transmitting equipment to maintain a mean test frequency. Power Outing Rating: [of transmitting equipment]: is the carrier power at which the transmitting equipment may be operated continuously into the test load. Spurious Emissions: are radio frequency signals appearing at the transmitting equipment output terminals on frequency other than the specified frequency and modulation products. References Telecommunications Act [No. 27 of2000]; Recommendation ITU-R BS.450-3: Transmission standards for FM sound broadcasting at VHF; RECOMMENDATION ITU-R BS.643-2: System for automatic tuning and other applications in FM radio receivers for use with the pilot-tone system; Page 26 of 26