Symmetricom 59552A, Руководство пользователя

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Chapter 2 Configuring Your 59552A/59553A
Configuring for One-Signal Distribution (Digital Mode Operation)
User’s Guide 2-9
Configuring for One-Signal Distribution
(Digital Mode Operation)
Overview of the Digital Mode
As shown in Figure 2-5, the Digital Mode provides for distribution of
one signal. The signal is typically the 1 PPS output from the 59551A
GPS Measurements Synchronization Module. The signal is connected
to the
Digital In (1 PPS)
BNC connector of the 59552A Fiber-Optic
Distribution Amplifier via a BNC cable where the signal is distributed
to each of the eight fiber-optic outputs of the 59552A (
Ch 1
through
Ch 8 ). Using a fiber-optic cable, each of these outputs can be connected
to the
Fiber Optic In
connector of an 59553A Fiber-Optic Receiver.
Finally, the 1 PPS signal is output at the Digital Out (1 PPS) BNC
connector of each 59553A to supply the timing signals to the system.
Digital Mode is intended to transmit a single digital signal.
The distribution system output replicates the system input. Waveform
characteristics such as pulse widths are preserved, with no inversion.
The system can transmit digital signals at rates from dc to 5 MBAUD.
Distribution delay depends primarily on the length of fiber line used.
The 2 microsecond delay typical of Combined Mode is not present for
Digital Mode, because the single digital signal does not use the
two-signal combining hardware.