Tektronix TDS7054, Service Manual

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Performance Tests
TDS7104 & TDS7054 Service Manual
4- 51
Locate the time reference
points for these waveforms
2
Display the waveforms
1
Read results
4
Align each cursor to the time
reference points
3
Figure 4- 22: Measurement of channel delay
g. Check against limits: Use the cursors to measure the skew from CH 1 to
CH 2, CH 1 to CH 3, and CH 1 to CH 4. Write down these three
numbers in the first measurement column of Table 4--8. Note that these
numbers may be either positive or negative.
h. Move the power divider on CH 1 to CH 2. Move the power divider on
CH 4 to CH 1.
NOTE
. To eliminate errors caused by the cables, the measurements are repeated
and averaged after swapping the channel position of the cables.
i. Repeat the procedure from step 1.c through 2.e .
j. Again use the cursors to measure the skew from CH 1 to CH 2, CH 1 to
CH 3, and CH 1 to CH 4. Write down these numbers in the second
measurement column of Table 4--8. Note that these numbers may be
either positive or negative.
k. Add the first CH 1 to CH 2 skew measurement to the second CH 1 to
CH 2 skew measurement and divide the result by 2. Use Table 4--8.