Oscillator Types - Safran SecureSync 2400 User Manual

SecureSync's internal oscillator is normally disciplined to an input reference (such
as GNSS, IRIG input, 1PPS input, etc.) in order to provide the highest degree of
oscillator accuracy and to account for oscillator drift. While disciplining (with a
1PPS input reference input present and valid), the oscillator's output frequency is
monitored and based on the measured frequency, the oscillator is steered to
maintain a very accurate 10 MHz output. If no valid 1PPS input references are
present (or input references are present but not considered valid), the oscillator
will be in Freerun mode instead.
The Oscillators Settings page provides the user with some control of the dis-
ciplining process. This page is also used to configure the length of time
SecureSync is allowed to remain in the Holdover mode when all references are
lost.
3.5.1

Oscillator Types

SecureSync units are available with different types of internal oscillators:
The two different types of OCXO oscillators are a precision OCXO oscillator and
a high-precision (low phase noise) OCXO oscillator. The two different types of
Rubidium oscillators are a precision Rubidium oscillator and a low-phase noise
Rubidium oscillator. All of these internal oscillators are self-calibrating and can be
disciplined to a 1PPS input reference for maximum accuracy.
To determine which oscillator is installed in your SecureSync unit, navigate to
MANAGEMENT > OTHER: Disciplining. The first entry in the Status panel on the
left indicates the type of oscillator:
Because of its high degree of stability, the Rubidium oscillator provides the
greatest ability to extend the hold-over period when input references are not
present. Extending the hold-over period allows the unit to provide very accurate
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3 SecureSync 2400 User Manual Rev. 5.2
TCXO (Temperature-Compensated Crystal Oscillator)
one of two different types of
oscillators, or
one of two different types of
3.5 Managing the Oscillator
OCXO (Oven-Controlled Crystal Oscillator)
Rb (Rubidium) oscillators.
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