Tektronix WVR6020, Technical Reference

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Video and General Performance Veri fi cation
Eye Signal Bandwidth
(Options EYE or PHY)
This test veri fi es the eye signal bandwidth.
NOTE.
The level accuracy of the RF generator and the frequency response of
the cable and matching pad directly affect this check. To accurately verify this
speci
fi cation with the recommended equipment, the combination of generator, pad,
and cable must be characterized as described in Signal Spurce Characterization
for Eye Signal bandwidth.(See page 75, Signal Source Characterization for Eye
Signal Bandwidth.).
1. Assemble the signal source setup as characterized in Signal Source
Characterization for Eye Signal Bandwidth Veri
fi cation.(See page 75, Signal
Source Characterization for Eye Signal Bandwidth .)
2. Set the RF generator frequency to 100 MHz.
3. Set the RF generator level. (See Table 64.)
4. Connect the signal source output to the SDI A input and terminate the
connector with a 75
Ω terminator.
5. Press SDI A.
6. Check that the RF generator’s RF output is on, with no modulation.
7. Press CONFIG, and then select Utilities > Calibration. Press SEL to start
calibration.
8. Press the up arrow key to navigate the Eye Bandwidth Test calibration case.
9. Press SEL to begin this test.
10. Press the DISPLAY SELECT 1 button, and then press CURSOR to enable
cursor measurement of the waveform shown in tile 1.
11. Use the cursors to measure the waveform amplitude, and note this as the
reference amplitude. (If Option PHY is present, the Eye Amplitude readout in
tile 2 may be used instead of the cursors.)
12. Set the RF generator frequency to 2.0 GHz (600 MHz for WVR6020).
13. Set the RF generator output level to the corresponding setting. (See Table 64.)
14. Measure the waveform amplitude using cursors. (If Opt. PHY is present,
the Eye Amplitude readout in tile 2 may be used in place of the cursor
measurement.)
15. Calculate the high frequency response as follows: Response = 20 x log ( high
frequency Amplitude / Reference Amplitude).
This value must be greater (more positive) than –3 dB.
16. Record the high frequency response in the test record.
17. Set the RF Generator to 100 MHz.
90 Waveform Rasterizers Speci fi cations and Performance Veri fi cation