Technical data

3 Calibration
28 U2761A Service Guide
Amplitude Flatness (+20 dB Range) Verification
This procedure verifies the high frequency AC amplitude
flatness above 100 kHz on the +20 dB amplifier range
relative to 1 kHz.
1 Connect the power meter and power sensor together to
measure the output amplitude of the U2761A as shown in
Figure 3- 4.
2 Set the U2761A based on the following.
• Load impedance: 50
Ω
• Function: Sine wave
• Frequency: 100 kHz
• Amplitude: 1.750 Vrms (+17.871 dBm)
3 Set the power meter Filter Mode to Auto if you have
previously set it to Manual.
4 On the power meter, use the Relative Power function to set
the current reading as the reference value. This will allow
you to compare future measurement result in dB.
5 Set the power meter Offset to Offset
+20dB
value previously
calculated in Table 3- 6. The power meter will directly
read the flatness error specification relative to 1 kHz.
6 Set the U2761A to each output listed in the Table 3- 9.
Measure the output amplitude using the power meter (the
relative measurement in dB).
7 Compare the measured output with the test limits shown
in the Table 3- 9.