Tektronix TG700, Руководство пользователя

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Operating Basics
Frame reset signal 1 is not synchronized with frame reset signals 2 or 3 unless
a GPS7 module is installed. When a GPS7 module is installed, the frame reset
signal 1 synchronization is related to the frame reset signals 2 and 3 through
the GPS7 epoch timing.
You can see which of the three frame reset signals are used by each output of
each module by using the FRAME RESET STATUS submenu. (See page 2-21,
FRAME RESET STATUS Submenu .)
Clock Con fl ict Messages
The TG700 uses various shared clocks to operate the mainframe and to output test
signals from the installed modules. In some cases, when you change the signal
format of a module output, the associated SD or HD clock frequency changes to
support the new format.
If you attempt to change the signal format of a module output, and if that format
change requires a frequency change to the SD or HD clock being used by the
output(s) of any other installed module(s), a clock con
fl ict occurs since the
instrument cannot output both of the requested signal formats simultaneously.
In this case, the TG700 displays a Clock Select message asking whether you
want to disable the currently used clock to enable the signal format change you
have input. Press
ENTER to enable the signal format change or press CANCEL
to cancel your signal format change.
After you enable the signal format change, you need to change the signal format
of the other output(s) that were using the SD or HD clock that you just changed.
CAUTION.
If you disable a clock that is being used by another signal output, the
timing of the other signal output will no longer conform to its con fi gured format.
Examples of speci fi c conditions under which the clock con fl ict message is
displayed are described below.
SD Clock Con fl icts If your DVG7 module has Option BK installed, an SD clock con fl ict message will
appear if you attempt to output 525-143 format signals and 525-270 (or 625-270)
format signals simultaneously from the module. For example, if you attempt set
the signal format for the BLACK outputs to 525-143 when the signal format for
the SIGNAL outputs is currently set to 525-270, the following message appears:
TG700 TV Signal Generator Platform User Manual 2–15