NF DF 1906, Инструкция по эксплуатации

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7.5 Performance Test
DF1906
7-4
7.5.1 Frequency Accuracy Test
Connection:
FUNCT ION OUT
→ Frequency counter input (50 Ω termination)
Use a coaxial cable.
Setting: Frequency 100 kHz, Amplitude 10 Vp-p/open, squar e wave after initializing the settings
Measur ement: Measur e the frequency with a frequency counter.
Judgment: ±25 ppm (99.9975 kHz to 100.002 5 kHz
）
, Pass
However, an aging error (±5 ppm/year) occurs with those for which many years have
elapsed s ince production.
7.5.2 Amplitude Frequency Characteristic Test
Connection:
FUNCT ION OUT
→ AC voltmeter (wide band type) (50 Ω termination)
Use a coaxial cable.
Setting: Amplitude 10 Vp-p/open after initializing the settings
Measur ement: First, measure the voltage at 1 kHz and use the result as a reference value.
Change the frequency, measure the voltage, and convert it to a relative value [dB] from
the reference value.
Judgment: ±0.2 dB (100 kHz or less), +1 dB/-3 dB
（
100 kHz to 2 MHz
）
, Pass
7.5.3 Sine Wave Distortion Test
Connection:
FUNCT ION OUT
→ Distortion meter (50 Ω termination)
Use a coaxial cable.
Setting: Amplitude 10 Vp-p/open after initializing the settings
Measur ement: Change the frequency and measure the distortion.
Set the frequency bandw idth of the distortion meter to 500 kHz or less.
Judgment: 0.1% or less (10 kHz or less), 0.2% or less (10 kHz to 100 kHz) , Pass
7.5.4 Square Wave Duty Ratio
Connection: FUNCT ION OUT
→ Oscilloscope (50 Ω termination)
Use a coaxial cable.
Setting: Amplitude 10 Vp-p/open, square wave after initializing the settings
Measur ement: Measur e the duty ratio with an oscilloscope. ( Unless the duty ratio measurement
accuracy of an oscilloscope is much better than 1%, subtract the oscilloscope's accuracy
from the acceptable error of 1% and make a judgement.)
Judgment: Duty ratio 50%±1% (49% to 51%) , Pass
When the duty ratio is other than 50%, or the frequency is less than 1 kHz, ther e is a
jitter of approx. 150 ns.
In this case, use a measur ing instrument that can measure the aver age value of the duty
ratio.