This standard specifies the scale and size of frequency characteristic graphs and polar coordinate graphs for drawing frequency response curves (or spectra) and directivity patterns. This standard does not apply to audiograms. GB/T 3769-1983 Scale and size of frequency characteristic graphs and polar coordinate graphs GB/T3769-1983 Standard download decompression password: www.bzxz.net
This standard specifies the scale and size of frequency characteristic graphs and polar coordinate graphs for drawing frequency response curves (or spectra) and directivity patterns. This standard does not apply to audiograms.
Some standard content:
National Standard of the People's Republic of China Scales and sizes for plotting frequency characteristics and polar diagrams Scales and sizes for plotting frequency characteristics and polar diagrams LDC 534.5 GB 3T69—E3 This standard specifies the scales for frequency characteristics and polar diagrams used to plot frequency response curves (or spectra) and directivity patterns. This standard is not applicable to audiograms. This standard refers to the international standard 1EC263 (1975) "Scales and sizes for plotting frequency characteristics and polar diagrams". 1 Scales and sizes of frequency characteristics 1.1 The horizontal axis is the frequency coordinate. The length of each decade (frequency ratio 10:1) is usually mm, and can also be 10m when it is affected. There are two scaling methods: a, logarithmic scale. Generally used for plotting frequency response curves (see Figure 1). h. Velvet scale. Each octave is divided into 1/3 octaves, and each octave is marked according to the nominal value of its center frequency. One section is used to draw 1/3 octave or 1/1 octave frequency (Figure 2). 1.2 The vertical half coordinate is linearly scaled in decibels. The length of each 10dB, 25dB, 50dB to 75dB is usually 50mm or 100mm. 2 Scale and size of polar coordinate diagram Polar coordinate diagram is linearly scaled in decibels along the radial direction, and the increase in decibel number from the non-marked circle is expressed. Generally, the radius of the non-marked circle is 19mm, and the maximum marked circle radius minus the non-marked circle radius is 100mm. If necessary, 50mm can also be taken, corresponding to a step difference of 50dB or 25dH (see Figure 3). 75.50.25.10 60,40.20.8 46.30,15.center .20,10,4 15.10.5.2 National Bureau of Standards 1983-06-28 Figure 1. Logarithmic scale for frequency coordinates 1984-05-01 implementation 75.6025.1 45.30,15.5 5.10.6.2F GB 3769:—83 f (tl) Figure 2. Linear scale for frequency coordinates Polar coordinates Additional notes: CB 3769:83 This standard was jointly developed by the National Technical Committee on Acoustics Standardization. National Technical Committee on Acoustics Standardization Re-elected member: Ma Daxian Vice-chairman: Yu Bo, Wu Dasheng. Xu Weiyi This standard was proposed by the Acoustics Basic Subcommittee. Acoustics Basic Subcommittee Former member: Ma DaxianwwW.bzxz.Net Vice-chairman: Hao Wenhong Members: Wei Rongjue, Du Lianyao, Guan Dinghua, Li Peizi, Zhang Jialu, Yang Jingang, Fang Zhi, Li Lin, Liu Dongniu, Jiang Shenghua, Chen Xiancai, Zhang Ruwei. This standard was drafted by the compilation group of "Standards for Acoustics Terminology, etc." Team leader: Ma Daxian Team members (in alphabetical order): Yu Nian, Ru Yu, Shen, Zheng Chenghao, Li Zhen, Yang Jingang, Zha Jixuan, Xu Xingyi, Qian Wen, Jing Ruwei, Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.