LDM-170 
LDM-171厂家: 日本利达
range:0.3%,1%,3%,10%,30% and 100% full scale
accuracy:±5% of full scale,at 30% and lower ranges
frequency range:20Hz to 20KHz(FUNDAMENTAL)in three bands;calibration accuracy within ±5%
balancing controls provided
input voltage range: 0.35 to 30Vrms
input impedance:Approx.100kΩ;less than 50pF in shunt
fundamental suppression:over 70dB
residual distortion:liss than 0.03%
harmonic attenuation:within 0.5dB(2nd and 3rd harmonics)
S/N(Noise)Measurement
range:0 to 70dB below the reference level
input voltage rage:0.35 to 30Vrms
level measurement
voltage range:1mv to 300Vrms in 12 ranges; minimum reading ,0.1mv
accuracy:±5% of full scale
frequency range:20Hz TO 200KHz
Highpass filter:cutoff at 500Hz;6dB/octave attenuation
monitor output:Approx.1Vrms at full scale reading;output impedance,approx.1KΩ
全音频范围内测量失真及电平
高灵敏度测量失真率，满刻度0.1%,能清晰显示低至0.02%的失真
失真测量:
频率范围:20Hz-20KHz
测量范围:0.1,0.3,1,3,10,100%满刻度共七档
输入范围:0.35-1V,1-3V,3-10V,10-30V共四档
输入限制：最高30V最低350mv
滤波器特性:
基波抑制:不少于80dB
谐波衰减:最大0.6dB（2次和3次谐波）
自动捕捉范围：1，0.3，0.1%
电平测量：
频率范围:20HZ-200KHZ
测量范围:0.3mV,1mV,3mV,10mV,30mV,100mV
0.3V,1V,3V,10V,30V,100V共12档
频率响应:0.03V档:20HZ-20KHZ±0.05dB
其余各档:20HZ-30KHZ±0.05dB
输入阻抗：1MΩ
信噪比测量：0-80dB
高通滤波器：400HZ，12dB倍频程
The LDM-171 also features S/N measurements to 80 dB and signal level measurements over a wide range further enhancing the value of the instrument on the audio bench. A high-pass filter (cut-off frequency at 400 Hz) and monitor output terminals for identifying distortion products are provided. All of this versatility packaged into one compact, neatly designed instrument is certainly a welcome addition to any audio bench.
KEY FEATURES
Function switches select mode for distortion, signal-to noise ratio or AC
volt/millivolt measurement. Input terminals accept up to 100V rms for level
measurements and to 30 V rms for THD or S/N. Set level range switch for more
than one-third full-scale deflection relative to the input signal level for THD
and S/N ratio measurements. Set level vernier for full scale set reference 0.35
to 30 V rms. Output for monitoring and characterizing distortion and noise
products on an oscilloscope. Range switches are used to enter the set level
mode, and then to select the measurement range sensitivity. Mode switch selects
auto-nulling at 1% or less to speed THD measurements. Frequency fine control is
used during manual distortion measurements. Frequency range vernier nulls
fundamental frequency component during THD measurements. Balance coarse/fine
controls are used to balance the bridge during distortion measurements.