Symmetricom ATS-6511A User Manual page 91

[OK] 2011-06-10T17:01:35Z
ATS-6511B>
Distribution Delay (dist_delay):
Description: Distribution delay is a critical factor in ensuring that the system is providing
accurate timing outputs at the on-time point (OTP) of the system. The OTP is normally
defined by the system designer and may not be the back panel of the ATS 6511.
The distribution delay value should be set to the actual propagation delay from the rear
connector of the ATS 6511 to the on-time point of the system. The system will then
advance its internal calculation of time by an equivalent amount to offset the delay caused
by the distribution system.
Changing the distribution delay value while a system is operating will result in a change in
the output signals in order to realign them with the correct time. All signals will remain
coherent with one another but the frequency of the system will be altered for a period of
time until the output PPS is aligned properly in time.
Syntax: dist_delay [nt]
Command Example:
ATS-6511>dist_delay 5.0E-8
OK
[OK] 2010-05-27T19:29:58Z
Verify the system settings using the settings pps_adjust command.
ATS-6511A>settings pps_adjust
[distribution_delay] 5.000000000000000e-08
[OK] 2011-06-06T19:46:36Z
Fiber Delay:
Description: The fiber delay for each path from the 4372A or 4372A-T module to the
ATS 6511 must be determined and set via the fiber_delay command in order to provide on
time 1 PPS from the ATS 6511 when using in legacy or two_way_disabled mode. A
portable clock and time interval counter can be used to measure the 1 PPS delay from the
ATS 6501 output to the ATS 6511 output. This value is determined for the channel A and
channel B path to the ATS 6511, and then must be programmed into the ATS 6511.
Syntax: fiber_delay [Channel A(nt)] [Channel B(nt)]
Command Example:
ATS-6511>fiber_delay 9.63E-8 5.6E-8
Query:
ATS-6511>settings fiber:delay
[channelA] 9.630000000000000e-08
[channelB] 5.600000000000000e-08
ATS-6511A/B/C Users Guide
85
DOC 6511_Release K