DXD8/PTP User Manual (rev 2.15)
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5.2.3 WHAT IS REQUIRED FOR A TIME JAM TO PTP?
1. Reference must be BNC A or BNC B (menu 1.1). The BNC input must be set properly in menus 2.1 and/or 3.1.
2. The PTP port must be set as the BNC INPUT TIME JAM SOURCE (menu 1.2). The port will now show as set for Time Jam
[BNC Inputs] in menu 5.1 (blue letters indicate status and cannot be altered)
3. The PTP domain of the Time Jam Port must be set to the same domain as the PTP source in the proper menu (Menu 5.5)
When Time Jam is set as described, the words [Time Jam] will appear at the bottom of the display in the Reference line.
6. Time Menus
6.1 TIME STANDARDS (MENU 7.1)
The following time standards are available on the DXD-8 in addition to the local time:
•
TAI
: International Atomic Time, (used as a base by other standards such as UTC - no leap seconds).
•
UTC
: Coordinated Universal Time (time zone ‘0’ - w/ leap seconds).
•
GPS
: Global Positioning System time (no leap seconds - 19 sec behind TAI and currently 18 sec ahead of UTC).
•
Loran
: Long Range Navigation time (no leap seconds).
•
Local
: Local time is based on UTC and can have adjustments for time zone and Daylight Saving (menu 7.1).
With the PTP option, ‘PTP GM’ is added to menu 7.1, for which a time standard can be selected for the display.
•
PTP Grandmaster
, time received on the Ethernet port from the external PTP Grandmaster.
6.2 TIME & DATE DISPLAY (MENU 7.3)
With the PTP option, ‘Ext PTP Grandmaster’ is added to the list available in menu 7.3, where 2 different DXD times & dates
can be selected for the Time & Date display (see 6.1.2 in the DXD-8 manual).
7. Time Code Menus
Time Code is a separate option available for the DXD-8. It is described in a separate manual (DXD/LTC). However, with the
PTP option, menu 8.1 SMPTE 2059 SET UP becomes available.
7.1 SMPTE 2059 SETUP (MENU 8.1)
The Daily Jam is a process where the time code generator realigns precisely with the epoch
(midnight on Jan 1, 1970 TAI). This process occurs everyday, at the same time, as set in the
DAILY JAM TIME field.
•
Daily Jam Time:
The value entered in the DAILY JAM TIME field is the amount of time after
midnight, local time, at which the daily jam will occur.
Adjustments can be made in 10 minutes increments. Default value is 01 Hrs 00 Min, i.e. 1:00AM, local time.
•
Jam Time Recalculate
: Pressing the ENTER key while “Press Enter to Jam” is selected will cause the DXD to recalculate both
Jam Times, the time of the Previous Daily Jam Event and the time of the Next Daily Jam Event.
For time code, the Previous Daily Jam Event is the generator’s anchor point, until the Next Daily Jam Event. When the local
time is too close to the set Daily Jam Time, a manual change will not occur until the next day. By forcing the DXD to recalculate
both jam times manually, the operator has the option to make an immediate change.