HM-250

Auto-Tuning Distortion Meter HM-250

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Outline

The HM-250 is a distortion meter capable of 0.1% full scale measurement continuously over the frequency range of 20 Hz to 20 kHz??A???Ewith a typical residual distortion of 0.01%. It makes full use of pushbutton switches and provides a calibration which can be activated with a single operation regardless of the selected distortion measurement range. Carrier frequency elimination is performed by an automatic tuning technique??A???Ethereby greatly simplifying operation. The HM-250 is also usable as a high-sensitivity (100?…?EV f.s.) AC voltmeter.

Features

●Automatic Tuning To eliminate the signal carrier component, simply perform a rough adjustment. The automatic tuning function thereafter automatically tunes to the carrier for extremely simple operation. ●High Sensitivity The HM-250 provides 0.1% full scale as a distortion meter, and 100μV full-scale measurements when used as an AC voltmeter  (10 Hz to 200 kHz). ●Single-Operation Calibration Calibration can be activated with a single operation regardless of the selected distortion measurement range. ●X-Y Outputs for Waveform Observation When measuring distortion, the input signal carrier component is provided as the X-axis output and the harmonic component is provided as the Y-axis output (while the input signal is output in output voltage measurements). ●SPECIFICATIONS SPECIFICATIONS Distortion measurement Measurement range 0.1% to 100% full scale? in 1-3 steps (7 ranges) Input level 100mV to 100V (for 100% CAL)30mV min. (automatic tuning is possible) Carrier rejection ratio 80dB min. Basic frequency range 20Hz to 20kHz in three ranges? and fine adjustment Residual distortion 0.01% max. (typ)? (1kHz? Sensitivity max.) Harmonic characteristics 20Hz to 10kHz carrier: ±1dB10Hz to 20kHz carrier: ±2dB (for a harmonic frequency of 60kHz or lower and distortion of 30% or less) AC voltage measurement Measurement range 100μV to 100V full scale? in 1-3 steps Indication accuracy ±3% of full scale max. (referenced to 1kHz) Residual noise 5% of full scale indication or lower (input shorted? 0.1mV range) Frequency response 20Hz to 20kHz: ±0.5dB 10Hz to 200kHz: ±1dB (referenced 1kHz) Common specifications Indication Mean-value detection with rms-value indication (calibrated for a sinewave) X output Approx. 1Vrms (tuned at 100% CAL) (Output of input signal carrier component) Y output Approx. 0.5Vrms (at full scale) Harmonic component output for distortion measurements? and input signal output for output voltage measurement X and Y outputs impedance Approx. 2.2kΩ (unbalanced) Input impedance Approx. 100kΩ? 100pF max. (unbalanced) Maximum input voltage At ATT 0dB: 　120Vrms (60Hz or less) 　200VDC or 200V (DC ACpeak) At ATT 30dB or 60dB: 　140Vrms 　200VDC or 200V (DC ACpeak) Power source 100/120/220/240V (max. 250V) AC? 50/60Hz? Approx. 5W Case dimensions 212 (W)×133 (H)×272 (D) mm Maximum dimensions 212 (W) ×156 (H)×288 (D) mm Weight Approx. 3.7kg Accessories Instruction manual (1)  Power cord (1)  Accessory cable (2)