Tektronix TG700, Руководство пользователя

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GPS7 GPS Synchronization and Timecode Module
a loss of lock. Select one of the following recovery modes, and then press the
ENTER button to con fi rm the selection.
NOTE.
If the module timing is off by more than 20 ms when the GPS signal is
recovered, the module forces a jam phase timing recovery. In genlock mode, a jam
sync may occur if the timing has drifted more than 20
μ s.
Stay Legal: Adjusts the module timing to match the recovered GPS signal
while staying within the speci fi ed frequency offset and frequency rate of
change speci fi cations for NTSC and PAL reference signals.
NOTE.
It can take a long time for the module to recover in this mode since it takes
about 300 seconds to correct each 64 μ s line of timing error.
Jam Phase: Adjusts the module timing to match the recovered GPS signal
immediately but will typically cause a sync “shock” to the system.
Fast Slew: Adjusts the module timing to match the recovered GPS signal at a
rate 25 times faster than the legal rate without jumping.
3–116 TG700 TV Signal Generator Platform User Manual