NF HSA42011, Instruction Manual

Page: 67 / 86

6.4 Performance Testing
HSA42011 6-11
6.4.5 Measurement of sine wave distortion ratio
 Connection
Connect a signal generator, THD meter or
spectrum
analyzer and terminating resistor as shown in
"
Figure 6-5 Measurement of Sine Wave Distortion Ratio
".
 Setting
Set this product as follows:
Item Setting
Input A
Input impedance
50

Bias addition OFF, dial 5.00
Polarity switching (INVT) OFF
Gain setting

50 (CAL)
Terminating resistor
50

 Test procedure
・
40 Hz, 1 kHz
<1> Adjust the output level of the signal generator so that the output voltage of this product is
40 Vrms.
<2> Measure the sine wave distortion ratio at frequencies of 40 Hz and 1 kHz.
・
100 kHz
<1> Adjust the output level of the signal generator so that the output voltage of this product is
40 Vrms.
<2> Measure the 2nd to 10th harmonic spectrum at a frequency of 100 kHz, and convert it to the
distortion ratio.
Distortion ratio %=
10
V2
10 +10
V3
10 +
・・・ +10
V10
10
10
V1
10
×100
V
1
: Fundamental spectrum [dBm]
V
2
to V
10
: 2nd to 10th harmonic spectrum [dBm]