HP 37717C Calibration Manual page 322

Performance Tests
STS-3 Transmitter Output Waveshape (Option 120)
Figure 3-62
STS-3 All Zeros Mask
11. Select STS-3 TEST PATTERN [OFF] on the OTHER DEBUG FUNCTION
display.
12. Select PATTERN [2^23-1] on the display.
TRANSMIT
13. Adjust the Oscilloscope controls to display the eye diagram as shown in
Figure 3-63, STS-3 Eye Diagram Example. Check that the waveform meets the STS-
3 eye diagram mask. It may be necessary to adjust the V/div gain on the Oscilloscope.
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