Specifications

89
Chapter 3: Testing Performance
Test Pod 1 in the 1500 Mb/s mode
Determine and set Eye Finder Position (1500 Mb/s
mode)
16 Set the pulse generator frequency to half of the required value. If it was set
to 765 MHz, then temporarily set it to 383 MHz.
17 In the Eye Finder (Sampling Positions) window, expand “Label1 (4
channels)”.
18 Grab the blue bar for “Label1 (4 Channels)” and move it to approximately
3.1 ns. All blue bars will follow.
19 Run Eye Finder and note the average sampling position chosen by Eye
Finder:______ns. In the following example, the average sampling position
is 3.10 ns. Note that in this step, you place the blue bars in the last
complete narrow window that appears on the right in the Eye Finder
display. Then run Eye Finder. The position may be different based on your
test setup. Bring stray channels into alignment if necessary. See page 56.
20 Re-set the pulse generator frequency to 750 MHz plus the test margin (765
MHz).
21 In the Eye Finder window, align the blue bars vertically. See page 55.
22 Grab the blue bar for “Label1 (4 Channels)” and move it to the
recommended starting position you noted in the prior step.
23 Run Eye Finder again. Some eyes may close, but the eyes in the sampling
position you chose on page 89 should remain open. Realign stray blue bars