本帖最后由 笨鸟先肥 于 2018-2-22 10:52 编辑
连万用表能测 THD 都不知道, 还能自称大师?
这也是论坛一绝。
大学生不会查字典, 看不懂英文, 这是夜大还是蓝翔的大学部啊??
小数点也不会数, 这是解放前的大学?
对数也不会看? 这是明朝的大学???
Our audio analyzing multimeters combine audio band quality measurements and analysis with a broad purpose 6½-digit DMM—all in one half-rack instrument. They can measure total harmonic distortion (THD) over the complete 20Hz to 20kHz audio band and can compute THD+Noise and signal-to-noise plus distortion (SINAD).
Specifications
Distortion Characteristics
Voltage Range 100 mV, 1 V, 10 V, 100 V, 750 V (user selectable).
Input Impedance 1MΩ paralleled by <100pF.
Display Range 0–100% or 0–100.00 dB.
Resolution 0.0001% or 0.00001 dB.
Fundamental Frequency Range 20 Hz–20 kHz.
Harmonic Frequency Range 40 Hz–50 kHz.
Frequency Resolution 0.008 Hz.
Frequency Accuracy ±0.01% of reading.
Frequency Temperature Coefficient ≤100 ppm over operating temperature range.
https://www.tek.com/tektronix-and-keithley-digital-multimeter/keithley-2015-series-thd-and-audio-analysis-multimeter
https://zhuanlan.zhihu.com/p/33880583
https://zhuanlan.zhihu.com/p/33835484
https://zhuanlan.zhihu.com/p/32320392
https://zhuanlan.zhihu.com/p/33807183
https://zhuanlan.zhihu.com/p/33835456
https://zhuanlan.zhihu.com/p/33783884
老烧见了就躲的耳朵听力曲线测试
http://bbs.erji.net/forum.php?mod=viewthread&tid=2098177
老烧见了就躲的耳朵听力曲线测试
https://zhuanlan.zhihu.com/p/33807183
http://www.hd199.com/thread-1661541-1-1.html
老烧见了就躲的耳朵听力曲线测试
http://bbs.mydigit.cn/read.php?tid=2351619
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