Tektronix TG700, Руководство пользователя

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GPS7 GPS Synchronization and Timecode Module
DIAGNOSTICS Submenu Use this menu to view operation parameters for the GPS7 module. Because many
sync sources are never turned off, it makes sense to check them periodically.
These menus allow access to some internal nodes to forewarn of impending
problems. Module diagnostics provide status information only and do not affect
operating behavior. The following
fi gure shows the DIAGNOSTICS submenu.
Figure 3-74: GPS7 module DIAGNOSTICS submenu
TEMPERATURES.
This diagnostic displays the temperature of the GPS7 module.
TUNE. This diagnostic displays the following:
Phase — The phase between the GPS pulse per second and the internal master
time. A Tektronix Customer Service Representative may request these values
for troubleshooting installation issues, should they occur.
DAC — The DAC code that is tuning the oscillator. Useful for checking if a
unit is getting close to the end of the oven oscillator tune range.
GPS lock indicator — Displays the GPS lock state. When Boot is displayed,
it means the function is still in special modes needed to get started. When
Coarse is displayed, it means the function is still tracking signi fi cant changes
in the timing. When Fine is displayed, it means the function has stabilized to
the point that the loop only needs to make small changes.
VOLTAGE MON 1.
This diagnostic measures internal voltage supplies. If these
supplies are outside the nominal range, Warning appears, which means that the
instrument should be serviced.
VOLTAGE MON 2.
This diagnostic measures a voltage divider between a positive
and negative supply. If this diagnostic result is outside the nominal range,
Warning appears, which means that the instrument should be serviced.
PHASE DET RAMPS. This diagnostic monitors voltage ramps used in the phase
detector. If these voltage ramps are outside the nominal range, Warning appears,
which means that the instrument should be serviced.
NOTE. The following diagnostics (ADC BUS, GENLOCK INPUT, LTC
POS INPUT, and LTC NEG INPUT) are available only in modules with the
BLACK 1 / REF IN connector.
TG700 TV Signal Generator Platform User Manual 3–137