Tektronix WFM700 Series, Service Manual

Page: 74 / 194

Performance Verification
2- 42
WFM700 Series Waveform Monitors Service Manual
Figure 2- 14: Eye clock recovery bandwidth performance screen
9. Adjust the RF generator to add phase modulation to the signal as follows:
LFGEN2 Frequency 10 kHz
LFGEN2 Waveshape SINE
Phase Modulation Source LFGEN2
Phase Deviation 1.57 RADIANS
Phase Modulation ON
10. The displayed waveform should fill in with 1 unit interval (UI) of phase
modulation. See Figure 2--13.
NOTE
. 1 UI phase modulation is achieved when the peak positive phase
modulation exactly overlaps the peak negative modulation. The result is that the
sine wave is brighter where the peak positive and negative phase modulations
overlaps. Slowly adjust the RF generator phase deviation to become familiar
with the appearance of 1 UI phase modulation.
11. Adjust the RF generator settings as follows:
LFGEN2 Frequency 100 Hz
Phase Deviation 2.22 RADIANS
12. Adjust the RF generator LF2 frequency in 1 Hz steps until the displayed
waveform shows exactly 1 UI phase modulation. Note the LF2 frequency
setting. See Figure 2--13 on page 2--37.