Performance Verification
AFG3000 Series Arbitrary/Function Generators Service Manual 4-21
Amplitude Test
This test verifies the amplitude accuracy of the arbitrary/function generator. All
output amplitudes are derived from a combination of attenuators and 3 dB variable
gain. Some amplitude points are checked. This test uses a 50 Ω terminator. It is
necessary to know the accuracy of the 50 Ω terminator in advance of this amplitude
test. This accuracy is used as a calibration factor.
1. Connect the 50 Ω terminator to the DMM as shown in Figure 4-2 and measure
the register value.
Figure 4-2: 50 ohm terminator accuracy
2. Calculate the 50 Ω calibration factor (CF) from the reading value and record
as follows:
3. Connect the arbitrary/function generator to the DMM as shown in Figure 4-3.
Be sure to connect the 50 Ω terminator to the arbitrary/function generator
Output connector side.
Figure 4-3: Amplitude tests
CF (Calibration Factor) = 2 / (1 + 50 Ω / Measurement Ω)
Measurement (reading of the DMM) CF
Ω
Examples
50.50 Ω 1.0050 (= 2 / (1 + 50 / 50.50))
49.62 Ω 0.9962 (= 2 / (1 + 50 / 49.62))
DMM
BNC-Dual banana adapter + 50 Ω terminator
DMM
50 Ω BNC coaxial cable + 50 Ω terminator
CH1 Output
AFG3000 series
BNC-Dual banana
adapter