GB 13837-1997 Radio interference characteristics limits and measurement methods for sound and television broadcast receivers and related equipment
Some standard content:
ICS 33. 160. 20
M 74
National Standard of the People's Republic of China
GB13837—1997
eqvIEC/CISPR13:1996
Sound and television broadcasting Linits and methods of measurement of radio interference characteristics of sound and television broadcastreceivers and associated equipment1997- 07- 17 Released
State Administration of Technical Supervision
1998- 09-01 Implementation | |tt | "Limits and Measurement Methods of Radio Interference Characteristics of Television Broadcasting Receivers and Related Equipment", the technical content is equivalent to it. This standard is a supplementary revision to GB13837-92 Allowable values ??and measurement methods for interference characteristics of sound and television broadcast receivers and related equipment. In addition to keeping the technical content of GB13837-92 basically unchanged, this standard adds the following new content: the upper limit of the frequency range is extended to 18GHz, the disturbance power limit and measurement method, the output terminal useful signal and disturbance signal limits and measurement method, etc. As a mandatory national standard, this standard is not only the technical standard basis for enterprises to organize product production and sales, but also the technical basis for trade, engineering and other fields.
This standard will replace GB13837-92 from the effective date. This standard was proposed by the National Radio Interference Standardization Sub-Technical Committee. This standard is under the jurisdiction of the National Radio Interference Standardization Technical Committee. This standard was drafted by: Third Research Institute of the Ministry of Electronics Industry. The main drafters of this standard are Lin Jingping, Li Shunyang, Chen Wei and Gui Boping. GB13837-1997
IEC/CISPR Foreword
1) CISPR formal decisions or agreements on technical issues are formulated by all CISPR national committees and other member organizations in the subcommittee that are particularly concerned about the issue. , it expresses as much as possible the international consensus on the issues involved. 2) These decisions or agreements are for international use in the form of recommendations and are accepted in this sense by the CISPR National Committees and other member organizations.
3) In order to promote international consistency, CISPR hopes that each national committee will use the text of this CISPR recommendation document for national regulations as soon as conditions permit. Any differences between CISPR recommendations and corresponding national regulations should be clearly stated in the national regulations wherever possible.
This publication was developed by the CISPR/E Radio Receiver Interference Characteristics Subcommittee. This third edition replaces the 1990 Second Edition and its Third Amendment (1995) (including the First Amendment and the Second Amendment). This version constitutes a technical revision.
The text of this CISPR publication is based on the following document: FDIS
CISPR/E/116/FDIS
Voting Report
CISPR/E/122/RVD| |tt|| All information regarding the vote to approve this publication can be found in the vote report shown in the table above. The main content of this publication is based on CISPR Recommendation No. 24/4 described below. CISPR Recommendation No. 24/4: Limits and measurement methods for radio interference characteristics of sound and television receivers CISPR considers that
A) The limits and measurement methods for radio interference characteristics of sound and television receivers need to be revised, B) This article involves many differences from CISPR Recommendation No. 24 and IEC Publication No. 106. C) The latest information in this article is based on the understanding and use of CISPR Publication No. 13; D) CISPR Publication No. 13 also includes other CISPR Some contents of the recommendations require implementation of these recommended limits. CISPR recommends
that limits and measurement methods for radio interference characteristics of sound and television receivers should use the latest version of CISPR Publication No. 13 and its amendments.
(Replaces Recommendation No. 24/3 with this recommendation.) Chapter 6 of this publication comes from CISPR Recommendation No. 46/1\Significance of CISPR Limits" and CISPR Report No. 48" Statistical basis for determining radio interference characteristic limits. I
1 Scope
National Standard of the People's Republic of China
Limits and methods of measurement of radio interference characteristics of soumd for sound and television broadcast receivers and related equipment and television broadcast receivers and associated equipmentGB 13837-1997
eqEC/CISPR13:1996
replaces GB13837-92
This standard specifies the limits for the disturbance characteristics of sound and television broadcast receivers and associated equipment and measurement methods and statistical methods for compliance with limits.
This standard is suitable for measuring electromagnetic disturbance generated by sound and television receivers and related equipment, with a frequency range of 9kHz to 18GHz. 2 Referenced standards
The provisions contained in the following standards constitute provisions of this standard by being quoted in this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision and parties using this standard should explore the possibility of using the latest version of the standard listed below. GB284688 AM broadcast radio measurement method GB3174-1995 PAL-D television broadcasting technical specifications GB/T4365-1995 Electromagnetic compatibility terminology
GB/T61131995 Radio interference and immunity measurement equipment specifications 3 definitions
Except GB In addition to the definitions in /T4365, this standard adopts the following definitions. 31 sound broadcast receiver soundbroadcastrecelvers are equipment used to receive terrestrial, cable and satellite transmissions of sound broadcasts and similar services. 3.2 Television receiver televisiom teceivers are equipment used to receive terrestrial, cable and satellite transmissions of television broadcasts and similar services. Note
1 Units (such as tuners, frequency converters, amplifiers, equalizers, monitors, etc.) designed to perform only part of the functions of sound broadcasting or television broadcasting receivers should be considered as sound broadcasting or television broadcasting respectively. receiver. 2 Tuners for satellite broadcast reception and have demodulators, decoders, signal separators, DA converters, encoders (such as NTSC, PAL or SECAM encoders), etc.
3 for satellites Frequency converter for broadcast reception and has a device for converting signals to other frequency bands. 4The receiver, tuner or frequency converter can be tunable or can only receive a fixed frequency. 33 Related equipment associated equlpment Equipment directly connected to sound and television receivers, or equipment capable of producing or reproducing audio or video <for example audio amplifiers, active loudspeaker units, tape recorders, CD players, magnetic recording and playback equipment, VCD machine, video camera, etc.). Approved by the State Administration of Technical Supervision on 1997-07-17 and implemented on 1998-09-01
1
4 limits
4.1 Overview
GB13B37
—1997
When measured using the method specified in Chapter 5, the measurement results should not be greater than the limits specified in 4.2 to 4.6. Where two frequency ranges overlap, the more stringent limits should apply. For mass-produced equipment, a confidence level of 8% is required and at least 0% of the products meet the limit requirements.
4.2 Disturbance voltage injected into the power supply
shall be measured according to 5.2. The disturbance voltage limits are shown in Table 1. Table 19kHz~30MHz injection power supply disturbance voltage limit rate range
MHz
0. 009~0. 15
0. 15 ~0. 5
0 .5~5
5~~30
Note
Quasi-peak
To be determined
66~56
58
60
limit
dBμ
average
pending
56~46
46
50||tt ||The limit decreases linearly with the logarithmic increase of frequency in the range of 0.15MHz~05MHz. 1
2 If the value measured by the quasi-peak detector is not greater than the limit specified by the average value detector, it is considered that the measurement by the average value detector can also meet the limit requirements.
3 should be taken as the larger value between the two measurement results of grounding and ungrounding of the outer conductor of the antenna input end. 4.3 The antenna terminal disturbance voltage
should be measured according to 5.3. The disturbance voltage limits at the antenna end are shown in Table 2. The useful signal and disturbance signal levels at the radio frequency output end of 44 video recorders and other equipment should be measured according to 5.4. The limits of useful signals and disturbance signals at the RF output end are shown in Table 3. Table 230MHz~~1750MHz Antenna Terminal Disturbance Voltage Equipment Type
TV receivers
and video recorders
whose working channels are between
30MHz to 1GHz
Sound and TV Satellite Broadcasting
Receiver Tuner Unit
Adoption Instructions
Disturbing Sources
Local Oscillator
Others
Local Oscillator| |tt||Others
1): The CISPR publication states that this limit will be reduced to 46dBμV. 2
frequency
MHz
30-950
950~1750
30~1750
30~950
950~1 750
30~1 750
limit value (quasi-peak value)
dBμv
fundamental wave
harmonic
harmonic wave
fundamental wave
fundamental wave
46
46
541
46
46
54
46
Equipment Type
FM Sound Receiver
FM Car Radio
Longwave, Medium Wave, Shortwave
Sound Receiver
GB 13837—1997
Table 2 (End)
Disturbing source
Local oscillator
Frequency
MHz
30~~300
300~1000
Others
Local Oscillator
Others
30~-1 000
30~~300
300~-1000
301000
To be determined
Note: For the satellite broadcast receiver tuner unit, the "antenna end" refers to the "first intermediate frequency input end", The same below. Limit value (quasi-peak value)
dBuv
fundamental wave
harmonic
harmonic
fundamental wave
harmonic||tt ||Harmonics
30MHz~1750MHz output terminal useful signal and disturbance signal limit table 3
Source
Useful signal
Others
Frequency|| tt||MHz
30950
950-1750
30~1 750
To be determined
Limit value (quasi-peak value)
By
Carrier frequency and sidebandswwW.bzxz.Net
Harmonics
Harmonics
64
50
52
46|| tt||66
59
62
TBD
76
46
541
46||tt| |The limits specified in Table 2 and Table 3 correspond to a nominal antenna impedance of 75. For receivers with a nominal antenna impedance other than 75, the limits should be converted according to equation (1):
L = L + 10lg (Z/75)
where;Lz
The limit value of a receiver with a nominal input impedance Z, dBμVLn - the limit value given in Table 2 and Table 3, dBμV; - the nominal input impedance of the receiver under test,. 4.5 Radiated disturbance field strength or power
shall be measured according to 5.5. Radiation disturbance limits are shown in Table 4 and Table 5. Table 430MHz~1GHz radiated disturbance field strength limits Equipment types
working channels below
300MHz
TV receivers
and video recorders
Adoption instructions :
Disturbed source
Local oscillator
Others
1) The CISPR publication states that this limit will be reduced to 46dBμV. Frequency
MHz
30~300
3001 000
121.5
243
30~1 000
(1 )
limit value (quasi-peak value)
dB (μuV/m)
fundamental wave
harmonic
harmonic
57
62
56
40
47
TBD
3
Equipment Type
Working Channel Television receivers
and video recorders
between
300MHz ~ 1 GHz
||First IF terminal
FM sound receiver
Long wave, medium wave, short wave
Sound receiver
Equipment type
For satellite broadcasting Transmitted
Sound and television receivers
Tuner 1st IF
GB 13837—1997
Table 4 (End)
Disturbing sources|| tt||Local oscillator
Frequency
MHz
300~1 000
Others
Others
Local oscillator
Others
121.5
243
30~1 000
121.5
243
30~1000
30~300
300~1 000
30~1 000
To be determined
Table 51GHz~18GHz radiated disturbance power limit disturbance source
Local oscillator||tt ||Note: The measurement of field strength at 1GHz and 18GHz is to be determined. 4.6 Disturbance power
shall be measured according to 5.5. The disturbance power limits are shown in Table 6. Frequency
GHz
1~3
3~1B
1~3
3~18
Table 630MHz~~1000MHz interference Power limit
Frequency
Equipment type
Related equipment
(excluding video recorders under RF reception) Note
MHz
accurate Peak
4555
30300
3001000
1 The limit value increases linearly with frequency in the range of 30MHz~300MHz. 2Same as Note 2 in Table 1.
5 Measurement Methods
This chapter details standard measurement procedures and measuring equipment. To be determined
limit value (quasi-peak value)
dE (uV/m)
fundamental wave
harmonic
fundamental wave
harmonic Wave
Harmonics
TBD
56
66
40
47
TBD
40
47
To be determined
60
52
66
To be determined
Limit value (quasi-peak value)||tt ||dBpW
Fundamental
Harmonics
Limits
dBμv
5711
To be determined
571|| tt||To be determined
Average
35~45
To be determined
Deviations from this standard are allowed in actual measurements, for example, the use of broadband antennas, the size of the shielded room etc., but the measurement results provided should be comparable to those obtained using this standard method. Adoption Notes,
1) The CISPR publication states that this limit will be reduced to 4S dBpW. GB 13837—1997
In case of dispute, the method specified in this standard shall prevail. 5.1 Measuring equipment
5.1.1 Interference measuring instrument
See GB/T6113.
5.1.2 Artificial power supply network
Use the 50Q-50uH-52V artificial power supply network in the frequency range of 9kHz~150kHz, and use the 502-50uHV type artificial power supply network in the frequency range of 150kHz~30MHz. See GB/T6113. 5.1.3 Absorption clamp
See GB/T6113.
5.2 Measurement of disturbance voltage injected into the power supply
5 2. 1 Overview
The measured disturbance voltage includes narrow-band disturbance and broadband disturbance from time base circuits, video circuits and semiconductor rectifiers, etc. . In the range of 9kHz to 30MHz, use the artificial power supply network and interference measuring instrument specified in this standard to measure the disturbance voltage injected into the power grid by the equipment under test. For broadband disturbances, use a quasi-peak detector, and for narrowband disturbances, use an average detector. 5.2.2 Measurement arrangement
shall be measured in a shielded room, see Figure 1 and Figure 2. NOTE
1 Floor-standing equipment should be placed directly on the floor. If its enclosure is made of conductive material and is not equipped with insulating legs or wheels, it should be placed on insulating material not higher than 12 volts.
2 Measurement procedures for very large devices are under consideration. Adjust the device under test to receive the specified useful signal. The receiver should use a radiation field to provide useful signals. A small receiving antenna (see Figure 1 and Figure 2) should be connected to the receiver. If the receiver is equipped with an internal antenna, it should be disconnected. For other equipment, a closed circuit method should be adopted, and the specified useful signal should be directly fed to the equipment under test through a suitable waveguide connector on the wall of the shielded room. Note that for AM sound receivers equipped with ferrite antennas, the radiating antennas in Figures 1 and 2 should be replaced by loop antennas placed close to the equipment under test. The requirements for loop antennas are in accordance with GB2846.
The standard test signal for TV receivers and video recorders is the standard color bar signal. See Appendix A in GB3174 for its standard test chart. Similarly, the modulation of sound and images in radio frequency carriers should also comply with the provisions of GB3174. The input signal should be strong enough to obtain a noise-free image. Adjust the contrast, brightness and color saturation controls to produce a standard image with the following brightness values:
black bars
magenta bars
white bars
2 cd /m2
30 cd/m2
80 cd/m2
Note: If the brightness value of the magenta bar in the test pattern does not reach the specified value, its brightness should be set to may be larger, and indicate the actual brightness value in the measurement results. For television receivers equipped with teletext receiving devices, measurements must be made in the teletext receiving mode. The test pattern is shown in Figure 3. The standard test signals used for sound receivers and other related equipment are: a) FM receiver, RF signal, 1kHz FM, frequency offset 37.5kHz (50% modulation), b) AM receiver, RF signal, 1kHz AM, Modulation degree 50% e) Audio amplifier, 1 kHz sinusoidal signal;) ??Recorder, provided with a 1 Hz sinusoidal signal from a suitable standard tape or pre-recorded tape e) Record player, inducing a 1 Hz sinusoidal signal through magnetic coupling with a wire connected to the core of the pickup, Or provided by a standard record (if magnetic coupling is not possible);
f) CD player, provided with a 1Hz sine signal by a standard CD record, g) Electronic musical instrument, using a sine or similar waveform generated by pressing the high C key signal (approximately 523Hz). 5
GB 13837—1997
The input signal should be strong enough to give a noise-free audio output signal. Each control button of the device under test should be placed in the normal working position, and the audio output power should be adjusted to 1/8 of the nominal output power. Note: FM/AM receivers should be tested in FM mode. 5.2.3 Measurement steps
The equipment under test and the artificial power supply network are arranged as shown in Figures 1 and 2. See 5.1.2 for the artificial power supply network. The power cord between the equipment under test and the artificial power network on the ground should be arranged in the shortest possible path. The part exceeding 0.8m should be folded back and forth parallel to the power cord into a bundle of a.3m~0.4m.
Connect the ground of the equipment under test (such as the outer conductor of the antenna cable) to the ground end of the artificial power network with the shortest possible wire. If the device under test has an RF coaxial connector, the test should be conducted with the outer conductor grounded and ungrounded, and there should not be any additional grounding at this time.
If the device under test does not have an RF coaxial input connector terminal, but has a ground terminal, the terminal should be grounded before measurement. Perform a frequency sweep in the frequency range of 9kHz to 30MHz, and record the indicated value of the interference measuring instrument at each frequency point. 5.3 Measurement of the disturbance voltage at the antenna end
5.3.1 Overview
It is necessary to measure the disturbance voltage at the antenna end of the receiving equipment for the following two reasons: a) When the receiving equipment is connected to a shared antenna system, due to the interference signal It is easy to be transmitted to other equipment through distribution cables and amplifier systems,
b) When multiple independent antennas are installed very close to each other, interference between adjacent receiving equipment is mainly caused by coupling between antennas. To this end, an auxiliary signal generator is used to feed the radio frequency signal (see 5.2.2) to the antenna input of the device under test, and the device under test is tuned to make it in normal working condition.
5.3.2 The equipment under test with a coaxial antenna input end uses a coaxial cable and a resistive hybrid network with a minimum attenuation value of 6dB to connect the antenna end of the equipment under test, the auxiliary signal generator and the interference measuring instrument. See Figure 4.
Each port of the hybrid network must be well matched to the connected device. If not, a matcher or attenuator with a minimum attenuation of 6dB should be inserted.
Adjust the output level of the auxiliary signal generator. The input levels corresponding to the 5-antenna input impedance of the FM receiver and TV receiver/video recorder are 60dBuV and 70dBuV respectively. If necessary, connect an auxiliary amplifier to the output of the signal generator. For FM receivers, the signal is an unmodulated carrier; for television receivers, the signal is an image carrier (such as the image specified in 5.2.2) modulated by the complete video waveform including the color burst signal, and the relative amplitude and frequency are correct. unmodulated sound carrier. Correctly tune the receiver under test.
Tune the interference measuring instrument to the corresponding disturbance frequency and adjust it to give a suitable reference indication. Then replace the receiver under test with a standard signal generator. The output impedance of the standard signal generator should be the same as the nominal characteristic impedance of the connecting cable, and other test devices remain unchanged. Adjust the output level of the standard signal generator so that the interference measuring instrument obtains the same reference indication. Measures should be taken to prevent the radio frequency current flowing from the shell of the device under test to the surface of the outer conductor of the coaxial cable from entering the coaxial system and causing erroneous test results. For example, a ferrite tube can be placed on the coaxial cable to suppress it. Note: During the test, it should be noted that the output signal of the auxiliary signal generator may overload the input stage of the interference measuring instrument. 5.3.3 For equipment under test with a balanced antenna input end, if necessary, the distance between the equipment under test and the interference measuring instrument shall be 0.At 5m, insert a matching network, and use an unshielded balanced feeder to connect the device under test and the matching network to ensure correct matching between the device under test and the balanced-unbalanced converter and attenuate the asymmetric current, see Figure 5. If erroneous test results are caused by asymmetrical currents (usually confirmed by swapping the connections of the balanced feeder at the antenna end of the device under test), they can be suppressed by suitable means, for example, with ferrite tubes or stop filters. Note: Impedance transformers may include means to suppress any asymmetrical current flow. Other measurement steps are the same as 5.3.2.
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