Tektronix WFM8200 User Manual page 184

Application Example
Timing Multiple Inputs to a
Router
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compared to the analog reference. For the conversion, a D/A converter with
delay of about three microseconds is used.
In the Relative to Rear Panel mode, this three microsecond conversion delay
is accounted for in the displayed offset. In the Relative to Saved Offset mode,
it has no effect.
Use the Relative to: function to set the offset between a master signal and a
reference signal as the zero-point reference for time-down applications. The
Relative to: box indicates the chosen zero point for the timing display:
Rear Panel. In this mode (default), the offset is zero when the measured signal
input and reference are at the same timing at the reference at the instrument
rear panel. This setting was used in the Timing Display Method procedure.
Saved Offset. In this mode, you can save the timing from a master signal
relative to the reference as the zero point offset. Then route other inputs and
measure relative to this saved offset.
To time the inputs to a router.
1. Perform steps 1 through 5 of the previous procedure.
2. Route the signal you want as the master to the appropriate input, SDI or
Composite, and terminate properly.
3. Route the reference signal to the reference input and terminate appropriately.
4. Save the timing offset for the master input (MEAS > Save Offset > SEL) and
select the Relative to: Saved Offset mode from the pop-up menu.
NOTE.
You cannot save the timing offset if either the input or reference is missing
or unlocked. You also cannot save a reference when in internal mode. Saving an
offset in these conditions would lead to misleading results so it is not allowed by
the instrument. A warning message will appear on the screen if you attempt to
save the offset when it is not allowed.
5. Now select other inputs to the router to be connected to the instrument. For
each input, the relative timing will be displayed.
6. Adjust the timing offset at the master sync source to time down the inputs to
the router to match the master.
WFM8200 and WFM8300 Waveform Monitors