Tektronix TDS6404, Руководство по обслуживанию

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Performance Tests
TDS6000 Series Service Manual
4- 49
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 cables and adapters, the measurements are
repeated and averaged after swapping channel position of cables.
i. Repeat the procedure from step 2.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--6. 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--6.
l. Add the first CH 1 to CH 3 skew measurement to the second CH 1 to
CH 3 skew measurement and divide the result by 2. Use Table 4--6.
m.
Add the first CH 1 to CH 4 skew measurement to the second CH 1 to
CH 4 skew measurement and divide the result by 2. Use Table 4--6.
n. Check against limits: CHECK that the largest of the three results from
steps k, l, and m is between --30 ps and + 30 ps.
o. Enter the time on the test record.
Table 4- 6: Delay between channels worksheet
Coupling
First
measurement Second
measurement
Add first and
second
measurements
Divide sum
by 2
CH 1 to CH 2
skew
CH 1 to CH 3
skew
CH 1 to CH 4
skew
3.
Disconnect the hookup: Disconnect the cable from the generator output at
the input connectors of the channels.