NF WAVE FACTORY WF1967, Инструкция по эксплуатации

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15.3 Performance Test
WF1967/WF1968 15-9
15.3.5 Sine Wave Total Harmonic Distortion Test
Connection:
FCTN OUT → Audio analyzer (50Ω termination)
Use a coaxial cable.
If the audio analyzer does not have a 50Ω termination, install a
50
Ω terminator (feed through terminator) at the input of the instrument.
Setting: Set frequency to 20kHz after setting initialization. The following table shows the
amplitude.
Measurement: Measure the harmonic distortion up to the 7th order THD
7
(%). (Not THD + N)
When THD
7
cannot be measured directly, measure the harmonic distortion from the
2nd order to the 7th order (HD
2
～
HD
7
)(%) and obtain THD
7
(%) through calculation.
2
7
2
6
2
5
2
4
2
3
2
2 7
HD HD HD HD HD HD THD
+ + + + + =
Judgment: It is normal when the value falls within the following table.
Amplitude setting (Value at
50
Ω
load)
Total harmonic distortion
(THD
7
)
1Vp-p 0.04 % or lower
15.3.6 Sine Wave Harmonic Spurious Test
Connection:
FCTN OUT → Spectrum analyzer
Use a coaxial cable. Measure a signal up to approx. 24dBm. Use a coaxial attenuator
separately not to exceed the allowable input of the spectrum analyzer.
Setting: The following table shows the amplitude and frequency after setting initialization.
Measurement: Measure the harmonic spurious up to the 5th order and obtain the total value of
harmonic spurious
through calculation.
Make an attenuator of spectrum analyzer high until the relative level of the
fundamental wave is stable.
Using X2 to X5 (dBc) as the relative values of the harmonic spurious up to the 5th
order based on the fundamental wave, the total harmonic spurious can be obtained
with the following formula.
10
5
10
4
10
3
10
2
10 10 10 10
X X X X
Spurious Harmonic
+ + + =
Judgment: It is normal when the value falls within the following table.
Total value of the maximum harmonic spurious level up to the 5th
order
Amplitude setting
(Value at 50
Ω
load)
Frequency
setting
1MHz
Frequency
setting
5MHz
Frequency
setting
30MHz
Frequency
setting
200MHz
1Vp-p -60dBc or less -50dBc or less -40dBc or less -30dBc or less