3 performance tests, 1 frequency accuracy, 2 amplitude accuracy – B&K Precision 4078 - Manual User Manual
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5.3 Performance Tests
The following tests verify that the waveform generator operates and meets specifications.
Perform the tests after a warm-up period of 30 minutes at an ambient temperature of 22°C ±
3°C.
You can use these tests for periodic inspection and for inspection after repair.
NOTE
In the following procedures, all test conditions for the waveform generator are power-up
conditions with output ON, unless otherwise specified.
5.3.1 Frequency Accuracy
Specification: 0.002% (20ppm) for the DDS waveforms. 0.005% for the Arbitrary waveforms.
Procedure:
1.
Connect the OUTPUT connector to the counter input using a 50 ohm coaxial cable and a 50
ohm
feedthrough termination.
2. Select SQUARE to generate a square waveform with 1MHz frequency and 5Vp-p.
3.
Set the counter to measure frequency with maximum digits resolution.
4.
CHECK for a frequency reading between 999980 Hz and 1000020 Hz.
5.
Select ARB waveform. Press F1 - RATE and enter 1 us.
4
Connect the unit REF OUT connector (on the rear panel of the unit) to the counter, using the
coax cable and 50 ohms termination.
5
CHECK for a frequency reading between 999950 Hz and 1000050 Hz.
5.3.2
Amplitude Accuracy
Specification: ±1.0% ±10mV of programmed value, into a 50 ohms termination, for a waveform
frequency of 1KHz.
Procedure:
1.
Connect the OUTPUT connector to the input of the TRUE RMS DVM using a 50 ohm coaxial
cable and the 50 ohm 0.1% termination.
4
Set the DVM to measure ac volts.
5
Set the unit to generate a SINE wave signal with 1 KHz frequency and an amplitude of 10Vp-p
6
CHECK that the measured voltages on the DVM at 10Vp-p, 5Vp-p, 3Vp-p, 1Vp-p, 100 mVp-p
and 50mVp-p are in the accuracy range: