1[size=1em]测量信号幅度时的单位及其定义为:
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单位 | | | V | | | Vrms | | | Vp | | | Vpp | | | dBV | | | dBu | | | dBm | (毫瓦分贝)以600Ώ1mW为零电平的分贝 | | dBg | | | dBr | | | dBrinv | | | W | | | / s6 X+ ]' B0 |' a& x0 d
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2[size=1em]相对量的单位' Z2 ]" v" x; X& E
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功能 | | | THD+N Ratio | | | THD+N Ratio | | 20*lg[(噪声+失真)/(信号+噪声+失真)] | 2-Channel Ratio | | ChA=20*lg(A/B) , ChB=20*lg(B/A) | 2-Channel Ratio | | ChA=100*(A/B) , ChB=100*(B/A) | Crosstalk | | | S/N Ratio | | 20*lg((信号+失真+噪声)/(失真+噪声)) | $ h' C" z( m7 l
3[size=1em]频率单位
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单位 | | Hz | | F/R | | dHz | | Cent | | Octaves | | Decades | | %Hz | | d% | | MdPPM | | PPM | |
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( B7 I' f+ |% g1 W( q/ G8 P1[size=1em]各测试功能的选择:
2 j2 `1 u) l0 Q. }Amplitude | | Bandpass | | Bandreject | | THD+N Ampl | | THD+N Ratio | | SMPTE/DIN | | CCIF | | DIM/TIM | | Wow&Flutter | | 2-Ch Ratio | | Crosstalk | | DFD | 失真(总谐波失真+噪音)测试(以比率形式表示)
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