Section 1 General
1 Application scope
This standard is applicable to the standard measuring method of electroacoustic performance measurement of monophonic and stereophonic radio receivers for FM broadcast transmissions (including tuner, car radio, FM receiving part in combinational machine, as well as dedicated radio receivers for FM broadcast transmissions——all the above are referred to as receivers) .
2 Terms and requirements
2.1
values for voltage and current
root mean square (r.m.s.) quantities, unless otherwise stated
2.2
presentation of level
Levels of power, voltage and field strength are expressed in decibels, as shown in Table 1.
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2.3
carrier frequency
the mean value of the instantaneous frequency or the frequency generated in the absence of modulation, and for a perfect modulation system in which no d.c. component and no non-linear distortion are involved, the two values are the same
2.4
instantaneous frequency deviation
the difference between the instantaneous frequency of the modulated carrier frequency signal and the carrier frequency
2.5
peak frequency deviation
the peak value of the instantaneous frequency deviation
2.6
maximum system deviation
the maximum peak frequency deviation specified for the system under consideration, which is ±75 kHz in China
2.7
standard modulation frequency
see Table 2 for optimized modulation frequency
Section 1 General
1 Application scope
2 Terms and requirements
3 Main test circuit
4 Measuring instrument
5 Measuring conditions
Section 2 Sensitivity
6 Signal-to-noise ratio
7 Sensitivity
8 Input-output characteristics
Section 3 Rejection of interfering signals
9 Two signal selectivity
10 Intermediate frequency rejection
11 Image frequency rejection
12 Spurious response rejection
13 Capture ratio
14 Rejection of amplitude modulation
15 Tuning characteristics
16 Radio-frequency intermodulation
Section 4 Fidelity
17 Total voltage harmonic distortion
18 Total acoustic pressure harmonic distortion
19 Maximum active power
20 Total voltage frequency characteristics
21 Total acoustic pressure frequency characteristic
Section 5 Other performances
22 Hum
23 Single-signal whistles
24 Self-oscillation
25 Audio frequency mechanical vibration
26 High-frequency mechanical vibration
27 Frequency range
28 Intermediate frequency
29 Tuning indication accuracy
30 Scale error
31 Change in tuning frequency
32 Automatic frequency control characteristics
33 Local oscillator radiation
Section 6 Stereo
34 Stereo signal-to-noise ratio
35 Stereo sensitivity
36 Separation
37 Non-linear crosstalk
38 Balance degree
39 Stereophonic identicality
40 Stereo intermodulation
41 Rejection to pilot frequency, subcarrier frequency and their harmonics
42 SCA rejection