EN 60315-3-1999 en Methods of Measurement on Radio Receivers for Various Classes of Emission Part 3 Receivers for Amplitude-Modulated Sound-Broadcasting Emissions (Incorporates Ame.pdf

1、 STD-BSI BS EN 60315-3-ENGL 2000 Lb246b9 08414b9 047 Incorporating Amendment No. 1 to (renumbers the BS as and incorporating Amendment No. 1 to BS 4054-3:1996 BS EN 6031 5-3:2000), BS EN 6031 5-3:2000 BS EN 60 3 15-3 :2000 BRITISH STANDARD Methods of measurement on radio receivers for various classe

2、s of emission - Part 3: Receivers for amplitude-modulated sound-broadcasting emissions The European Standard EN 60315-3:1999, with the incorporation of amendment A1:1999, has the status of a British Standard. ICs 33.160.20 NO COPYING WlTEO“ BS1 PEBMISSION EXCEPT AS PEPMFITED BY COPYEIGET LAW STD-BSI

3、 BS EN b0315-3-ENGL 2000 m 1624bb9 0843470 8bO W Amd. No. BS EN 60315-3:2000 Date Comments Committees responsible for this British Standard 10596 The preparation of this British Standard was entrusted by Technical Committee EPU100, Audio, video and multimedia systems and equipment, to Subcommittee E

4、PL1100/1, Radio receivers, upon which the following bodies were represented: April 2000 Renumbers BS 4054-3:1996 as BS EN 60315-3:ZOOO and implements amendment No. 1 to the BS EN (see national foreword) British Broadcasting Corporation British Educational Equipment Association British Radio and Elec

5、tronic Equipment Manufacturers Association British Telecommunications plc Consumers Association Institution of Electrical Engineers Radio, Electrical and Television Retailers Association Radiocommunications Agency This British Standard, having been prepared under the direction of the Electrotechnica

6、l Sector Board, was published under the authority of the Standards Board and comes into effect on 15 August 1996 8 BSI 04-2000 The foiiowing BSI references reiate to the work on this standard: Committee reference EPL/l/l Draft announced in BSI News Update May 1996 ISBN O 580 26018 6 STD.BSI BS EN b0

7、315-3-ENGL 2000 m Lb24bb9 0841431 7T? m BS EN 60315-3:ZOOO Contents Page Committees responsible Inside front cover National foreword 11 Foreword 2 Text of EN 60315-3 5 O BSI 04-2000 i STDoBSI ES EN h0315-3-ENGL 2000 Lb2Yhb9 0843472 633 BS EN 60315-3:2000 National foreword This British Standard has b

8、een prepared by Subcommittee EPL1100/1. It is the English language version of EN 60315-3: 1999, including amendment A1:1999. It was renumbered by amendment from BS 4054-3:1996. It is identical with IEC 60315-3:1989, Methods of measurement on radio receivers for various classes of emission -Part 3: R

9、eceivers for amplitude-modulated sound-broadcasting emissions, including corrigendum March 1994 and including amendment 1: 1999, published by the International Electrotechnical Commission (IEC). The start and finish of text introduced or altered by amendment is indicated in the text by tags - BS EN

10、60315-4: 1998, Receivers for frequency-modulated sound broadcasting emissions; - BS 4054-5: 1980, Measurement on frequency-modulated receivers of the response to impulsive interference; - BS EN 60315-7:1966, Methods of measurement on digital satellite (DSR) receivers; - BS EN 60315-9:1997, Measureme

11、nt of the characteristics relevant to radio data system (RDS) reception. It is envisaged that other parts will be published in due course. References in the text to IEC page numbers should be ignored. Cross-references The British Standards which implement international or European publications refer

12、red to in this document may be found in the BSI Standards Catalogue under the section entitled ”International Standards Correspondence Index” or by using the “hd” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a cont

13、ract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity b) the standard radio-frequency input signal is applied via the appropriate antenna simulation network to the antenna terminals of the receiver (see T

14、able III and Figure 6 of Part 1) or applied to a standard magnetic field generator to induce the signal into the magnetic antenna of the receiver; c) the audio-frequency output terminals for connection to loudspeakers (if any) are connected to audio-frequency substitute loads, as are any other audio

15、-frequency output terminals, if measurements are to be made at those terminals; d) the receiver is tuned to the applied signal in accordance with sub-clause 2.2; e) the volume control (if any) is adjusted so that the output voltage at the main audio-frequency output terminals is 10 dB below the rate

16、d distortion-limited output voltage, or corresponds to a preferred reference value (see Part 1, sub-clause 16.1); 9 the environmental conditions are within the rated ranges; g) for stereo receivers, the balance control or its equivalent (if any) is adjusted so that output voltages of the two channel

17、s are equal; h) the tone controls (if any) are adjusted for the flattest possible audio-frequency response (e.g. for equal response at 100 Hz, 1 kHz and 10 kHz). This shall be carried out using an a.f. input signal if a.f. input terminals are available, otherwise the frequency of 10 kHz given above

18、should be reduced to 2 kHz; i) the automatic frequency control is inoperative, if this can be achieved by means of a user control (see note). NOTE Where a user control for automatic frequency control is provided, measurements should in general be made both with automatic frequency control off (which

19、 will allow easy analysis of the results), and with automatic frequency control on (which represents the situation when the receiver is in normal use). The two sets of results should be clearly identified. If the automatic frequency control cannot be made inoperative by means of a user control, it m

20、ay nevertheless be necessary (or desirable) for the automatic frequency control to be disabled for certain measurements. In this case the automatic frequency control should be disabled by temporarily modifying the receiver, the action taken being detailed with the results (see sub-clause 2.2); j) th

21、e muting control (if any) is in the “muting off position. 2.2 Tuning and automatic frequency control 2.2.1 Preferred tuning method If the manufacturer gives instructions on tuning the receiver, such as the use of a tuning indicator, these instructions shall be followed. In the absence of instruction

22、s or of a tuning indicator, the receiver shall be tuned for maximum output voltage at the main audio-frequency terminals under the conditions with exception of Item d) given in sub-clause 2.1, care being taken to avoid overloading the audio-frequency part of the receiver. 2.2.2 Effect of automatic f

23、requency control All tuning operations shall be made with arrangements for automatic frequency control inoperative, if this is possible, except when the performance of the automatic frequency control is being investigated. O BSI 04-2000 5 Previous page is blank STDmBSI BS EN b0315-3-ENGL 2000 1b24bb

24、9 0841437 115 W EN 60315-31999 When provision is made for the user to render the automatic frequency control inoperative, measurements may be made both with the automatic frequency control in operation, and with it disabled. The results shall clearly show whether the automatic frequency control was

25、in operation or not (see also Section 6). 2.3 Precautions Many of the measurements described in this part are likely to be adversely affected by interfering emissions and radio-frequency noise. It is usually essential that a screened room or screened enclosure is available in which to carry out thes

26、e measurements. It is also highly desirable to monitor the audio-frequency output signal continuously with a loudspeaker or headphones in order to detect any interference or spurious output signals due to unwanted signals from the test equipment or elsewhere, or spurious responses of the receiver. M

27、easurement accuracy is also affected by inadequate signal-to-noise ratio. When the noise output is independent of the modulation factor (which is not always so), the output with zero modulation should be checked and if it is larger than -10 dB (unless otherwise stated in this part) with respect to t

28、he output with modulation, the result of the measurement shall be rejected and measurement made using an a.f. band- pass filter to improve the signal-to-noise ratio sufficiently to restore accuracy. Section 2. Sensitivity and internal noise 3 Outputlinput characteristics 3.1 Introduction Virtually a

29、ll commercially-available receivers for amplitude-modulated sound-broadcasting emissions use some form of automatic gain control (a.g.c.). To investigate the sensitivity and noise characteristics of such receivers, it is useful to measure the a.f. output with a fured modulation factor, and the noise

30、 output with zero modulation factor, as functions of the r.f. input signal level and to plot the curves on the same graph. An example of such a graph is given in Figure 1, which also shows the characteristics whose values may be determined from the curves or the tabulated results of the measurements

31、. 3.2 Method of measurement a) The receiver is brought under standard measuring conditions (see sub-clause 2.1). An a.f. voltmeter (preferably a true r.m.8. meter) and a noise weighting filter and quasi-peak meter (see Part 1, sub-clause 6.2.2) are connected across the audio-frequency substitute loa

32、d at the terminals where a.f. output measurements are to be made. B NOTE 1 Unweighted noise measurements using a wide-band filter or A-weighting noise measurements may be made if required (see clause 6 of IEC 60315-1). In these methods, noise is measured with an r.m.8. meter (preferably a true r.m.8

33、. meter). The method used should be clearly stated with the resulta. a NOTE 2 If ultrasonic components within the bandwidth of the a.f. voltmeter may be present in the a.f. output voltage, the voltmeter should be preceded by a band-limiting fiiter in accordance with sub-clause6.1 of Part 1. b) The a

34、.f. output voltage on the a.f. voltmeter is noted. The modulation factor is then reduced to zero and the noise output voltage on the noise meter is noted. c) The measurements are then repeated for diferent values of r.f. input signal level, measurements being made at signal levels low enough to give

35、 very low signal-to-noise ratios and high enough (if possible) to explore the overloading of the r.f. part of the receiver (see clause 20). If overloading of the a.f. part of the receiver occurs at high r.f. input signal levels, the volume control attenuation is increased by a known amount to elimin

36、ate the overloading, and measurements are continued. This increased attenuation is taken into account in presenting the results. If no volume control is fitted, the onset of a.f. overload sets a limit to the permissible r.f. input signal level and measurements should be discontinued. d) Particularly

37、 at high input signal levels, the receiver tuning should be checked by adjusting the camer frequency of the signal source before each result is recorded, since the receiver may detune. The extent of any detuning shall be recorded in terms of frequency at each input signal level during this measureme

38、nt sequence, as the results are of value for the measurement of variation of operating frequency with r.f. input signal level (see Part 1, clause 3). NOTE It should be decided whether to record the results of the outpuffinput characteristic measurement with or without retuning. Unless the tuning var

39、iations are large, it is usual to record the result obtained without retuning. If retuning is carried out, this should be noted with the results. e) The measurements may be repeated with other values of modulation factor, such as 80 % (see Part 1, clause 17 and Table III). 8 BSI 04-2000 6 STD.BSI ES

40、 EN b03L5-3-ENGL 2000 3624bb 08431178 051 EN 60315-3:1999 3.3 Presentation of results The results of the measurement of the output/input characteristic and the noise outputlinput characteristic may be tabulated but are usually presented graphically, with input signal level in dB(fW) or dBpV/m) as ab

41、scissa and output or noise output level in dB as ordinate with respect to a stated reference usually rated (distortion-limited) output voltage. An example is shown in Figure 1. 3.4 Characteristics related to the outputlinput and noise outpuvinput characteristics 3.4.1 Amplification reserve The ampli

42、fication reserve is 10.6 dB greater than the difference between the a.f. output level measured with a high level or r.f. input signal, which shall be 90 dB(fW) or 94 dBV/m), unless otherwise stated and the rated (distortion-limited) a.f. output level, allowance being made for any attenuation introdu

43、ced by the volume control (if any) to avoid a.f. overloading. The r.f. input signal shall be the standard input signal except in respect of level. NOTE The factor 10.5 dB is introduced to allow for the modulation factor of the standard input signal being 30 %. The amplification reserve is thus relat

44、ed to 100 % modulation. 3.4.2 Gain-limited sensitivity The gain-limited sensitivity is the r.f. input signal level at which the a.f. output is equal to the rated a.f. output with any volume controls set at maximum gain. The r.f. input signal shall be the standard input signal except in respect of le

45、vei. 3.4.3 Noise-limited sensitivity The noise-limited sensitivity is the r.f. input signal level required to achieve a specified signal-to-noise ratio, which shall be 26 dB unless otherwise stated, referred to a signal with 30 % modulation (36.5 dB referred to 100 % modulation). The r.f. input sign

46、al shall be the standard input signal except in respect of level, so that the signal level in the signal-to-noise ratio calculation is that produced by 30 % modulation. The noise output of the receiver shall be measured with the psophometric weighting and quasi-peak meter (see Part 1, sub-clause 6.2

47、.2) unless otherwise stated (see also sub-clause 3.4.8). e; NOTE The unweighted noise measurement may be used if required. The method used should be clearly stated with the resu1ts.a 3.4.4 Noise factor The noise factor of a receiver is the ratio of the noise output voltage under specified conditions

48、 to the noise output voltage produced by the thermal noise of the resistive part of the source impedance. Although it is theoretically possible to calculate the latter output, in practice it is easier and more accurate to determine the noise factor directly by using a noise generator whose output le

49、vel is calibrated directly in terms of noise factor expressed in decibels. To do this, the receiver is brought under the required conditions for measuring noise factor, with the noise generator connected to the antenna terminals through the appropriate antenna substitution network. The output of the noise generator is set to zero and the noise output measured with the wide-band filter and true r.m.s. meter (see Part 1, sub-clausedl). The noise generator output is then increased until the noise output level has risen by 3 dB. The noise factor can then be read from the ou