Model 5601MSC
Model 5601MSC Master SPG/Master Clock System
Page - 90
Revision 2.2
MASTER CLOCK
4.3.
CONFIGURING THE INPUT REFERENCES
The
INPUT
menu is used to set up various items related to the input references of the 5601MSC. The
chart below shows the items available in the
INPUT SETUP
menu. Sections 4.3.1 to 4.3.12 give
detailed information about each of the sub-menus.
Frequency Ref
Contains items controlling the frequency reference and how to lock to it
Time
Contains items related to the time reference and how to lock to it
Jam Input
Contains live controls that can force the 5601MSC to lock immediately to
the frequency or time reference
Table 4-5: Root Level of the INPUT Menu
4.3.1. Selecting the Frequency Reference
INPUT
The
Reference Src
menu item in the
Frequency Ref
menu is used to select
the frequency reference that the 5601MSC will use to lock its internal
oscillator. All outputs are driven from a common oscillator and therefore are
clock locked to each other (i.e. they do not drift with respect to each other).
When set to the different possible reference sources and the appropriate
reference is supplied, the phasing of the video and DARS outputs is
affected as shown in the lock diagram in section 2.2.
When set to
GPS
the 5601MSC will lock its ovenized oscillator to the 1pps
pulse from the GPS smart antenna. Selecting this option forces the
Genlock
Range
to Narrow. All outputs are phased with respect to a specific date in
GPS time. This forces the time reference to GPS time. The GPS-disciplined
internal oscillator will maintain superb long-term accuracy. Refer to section
2.2.13 for more information.
When set to
10 MHz
the 5601MSC will look for a 10MHz or 5MHz frequency
reference on the reference loop input. It will lock in either Narrow or Wide
mode, depending on the
Genlock Range
setting. The 10MHz or 5MHz
reference supplies no phase information and the phase of the outputs will
change if the unit is powered down and rebooted. The phase between
different 5601MSC units locked to 5MHz or 10MHz will not be the same.
When set to
Video
the 5601MSC will lock to a valid black burst or tri-level
video signal applied to the reference loop inputs. The
Genlock Range
menu
item is used to select the tolerance of the master oscillator lock range. Note
that the 5601MSC requires a colorburst on NTSC and PAL references, with
a SCH error of less than 35º. Burst is not required for Slo-PAL bi-level
references. Refer to section 2.2.5 for more information.
When set to
Internal
the 5601MSC will free-run on its internal ovenized
oscillator. This forces the
Genlock Range
to Narrow. The stability of this
ovenized oscillator is 0.01ppm, which corresponds to a time drift of about
0.31 seconds per year. Refer to section 2.2.12.1 for more information.
Frequency Ref
Reference Src
GPS
Ten MHz
Video
Internal