This section describes the reference source types and lock condition indicators.

The title bar displays the source that is determining the RF output accuracy as described below:

1600 MHz external

100 MHz external

1PPS external, GNSS/GPS Atomic Clock Receiver (Option 66) or Ultra Stable Rubidium Reference (Option 56) installed.

10 MHz external

Internal GPS, GNSS/GPS Atomic Clock Receiver (Option 66) only.

Internal 10 MHz Rubidium clock, Ultra Stable Rubidium Reference (Option 3) only.

Internal 10 MHz free running, Low Phase Noise and Ultra High Stability (Option 3) only.

Internal100 MHz free running.

Note: For EXT 1PPS, EXT 10, INT GPS, or INT RB, the value may contain “Acquiring” instead of “REF” while the system is in the process of acquiring lock to this reference.

The reference oscillation lock condition is described below.

Low Phase Noise and Ultra High Stability (Option 3) is installed. Values vary based on installed options.

Low Phase Noise and Ultra High Stability (Option 3) are not installed (standard reference). Values vary based on installed options.

Attempting to acquire lock to the reference source indicated by Low Phase Noise and Ultra High Stability (Option 3); or, attempting to acquire lock to an external 10 MHz reference Low Phase Noise and Ultra High Stability (Option 3) are not installed.

100 MHz reference is locked to an external 10 MHz reference and Low Phase Noise and Ultra High Stability (Option 3) are not installed; or, 10 MHz reference is locked to an external reference, either 10 MHz or 1PPS with Low Phase Noise and Ultra High Stability (Option 3) installed.

10 MHz reference is locked to an internal Rb reference Ultra Stable Rubidium Reference (Option 56) installed.

10 MHz reference is locked to an internal GPS 1PPS reference. GNSS/GPS Atomic Clock Receiver (Option 66) installed

100 MHz reference is free running Low Phase Noise and Ultra High Stability (Option 3) is not installed); or, 10 MHz reference is free running Low Phase Noise and Ultra High Stability (Option 3) installed.

100 MHz reference can't lock to a connected external 10 MHz input Low Phase Noise and Ultra High Stability (Option 3) not installed: or, 10 MHz reference can't lock to a connected external reference, either 10 MHz or 1PPS (Low Phase Noise and Ultra High Stability (Option 3) installed.

10 MHz reference can't lock to the internal Rb reference Ultra Stable Rubidium Reference (Option 56) installed.

10 MHz reference can't lock to the internal GPS reference 1PPS. GNSS/GPS Atomic Clock Receiver (Option 66) installed.

 

The 100 MHz reference lock status is described below:

Attempting to lock the 100 MHz to an external 10 MHz reference. Low Phase Noise and Ultra High Stability (Option 3) is installed; or, attempting to lock the 100 MHz to the internal 10 MHz reference. Low Phase Noise and Ultra High Stability (Option 3) is installed

100 MHz is locked to the external 10 MHz. Low Phase Noise and Ultra High Stability (Option 3) is not installed; or, 100 MHz is locked to the internal 10 MHz reference. Low Phase Noise and Ultra High Stability (Option 3) is installed.

100 MHz is free running

100 MHz is unable to lock to a connected 10 MHz. Low Phase Noise and Ultra High Stability (Option 3) is not installed; or, 100 MHz is unable to lock to the internal 10 MHz reference, Low Phase Noise and Ultra High Stability (Option 3) is installed.

Requires GNSS/GPS Atomic Clock Receiver (Option 66). The GPS reference 1PPS lock status is described below:

The GPS reference is locked

The GPS reference is acquiring lock

The GPS module in turned off

The GPS reference is unable to acquire lock

Requires Low Phase Noise and Ultra High Stability (Option 3) and Ultra Stable Rubidium Reference (Option 6). The Rubidium reference lock status is described below:

The Rb internal TCXO is locked to the vapor chamber.

The Rb internal TCXO is acquiring lock to the vapor chamber.

The Rb internal TCXO is unable to acquire lock to the vapor chamber.