Symmetricom TimeSource 500, User Manual

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TimeSource 3500
Description
097-72050-01 Issue 7: August 2003
S S S S S S S S S S S S S S S S S S S S S S S S S S S S S
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terminal unless it can be extended by further analysis, such as in
rolling the sphere to be tangent to earth.
If the wall antenna is installed outside the zone of protection,
Symmetricom offers an outdoor and/or indoor lightning protector
kits for these installations. Refer to Chapter 2, Engineering &
Ordering, for more information on these kits.
IF Interface
An IF interface accepts the signals from the antenna/IF converter,
and provides the clock information to the BesTime Ensemble
Timing Generator.
GPS Receiver
The GPS Receiver continuously tracks up to eight satellites, using
both carrier and code lock. The recovered pseudo-range
measurement data is processed to determine precise time and
frequency state estimates for the local oscillator. The receiver
software is optimized to track and update state estimates, when as
few as one satellite is in view.
Local Oscillator
A rubidium oscillator, based on a digitally controlled servo-loop,
provides an ultra-stable local oscillator signal, which is sent to the
BesTime Ensemble Timing Generator.
Clock Extractors
A clock extractor circuit extracts a timing signal from each
external reference source. (External sources, other than the GPS
antenna, are optional.) The extracted timing signal is sent to the
BesTime Ensemble Timing Generator.