Radyne ComStream TIERNAN SE4000, Инструкция по установке и эксплуатации

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SE4000 MPEG-2 Contribution Encoder Introduction
01-0934-401-B 2-7
2.5.2.2 Clock Interface Configuration 2
If the DTE cannot turn around the ST, but has an internal clock source that can be provided as TT
to the SE4000, use this option to configure the auxiliary data channel.
The following block diagram shows the clock configuration for a DTE providing an internal clock
source as TT to the SE4000.
In this configuration, the DTE clock is set to internal and the SE4000 auxiliary data channel clock
source is set to external. The DTE uses its internal clock source to time the data, sends the data
to the SE4000 on SD, and sends its internal clock to the SE4000 as TT. The SE4000 uses TT to
latch the data. The SE4000 auxiliary data channel must be configured for an external clock
source.
2.5.2.3 Clock Interface Configuration 3
If the DTE cannot turn around the ST, and does not have an internal clock source that can be
provided as TT to the SE4000, configure the SE4000 to use the ST to latch the data. However,
this scenario is not recommended and should be considered only if neither of the other two-clock
source configurations can be used.
The following block diagram shows the clock configuration for a DTE configured for an external
clock and a SE4000 auxiliary data channel configured for an internal clock.
In this scenario, both the DTE and the SE4000 use ST, but the ST is provided to the DTE on one
path and to the SE4000 on a different path. Depending upon the length of cable between the
DTE and the SE4000, the clock may be received out of phase at the SE4000. The longer the
cable, the further out of phase the clock will be.