Revision request - Time on Cablecast start again?

I'll chip in here to give you the simple facts, and you can all judge for yourselves what this means.

Cablecast syncs with externally timed devices in one of two cases. First is when you send autopilot, and second is every X seconds, where X is the number entered under "Time Sync" in "System Settings" within Cablecast.

Now as you all can imagine, this is a pretty simple process. The Cablecast server says its X time, so the slave devices thus set their clocks to X time. From that point forward its up to the devices internal clocks to keep ticking correctly until the next time sync. (Again, X minutes as set or the next Autopilot send.)

Now there are two situations I can think of offhand that could throw timesyncing off.

First, if you have more than one Tightrope system set to update your Leightronix or other devices. This actually happened to John Goran, where he had an old machine that wasn't being used but still in the rack and connected to the network. His current system would set the clock to "X" and the old system would then set the clock to "Y" a couple minutes later. What you end up seeing is a "Tug of war" between the two time-sync devices. The solution here is to remove the second time-sync device so only one is trying to change the times.

Second, if you have two types of time-syncing software on your machine, those can actually conflict with eachother on your Cablecast machine. Say at 10AM your Cablecast machine is synced with program A, and at 10:30 it syncs with your Leightronix. Then at 11AM the Cablecast machine syncs with program B, changing its time by a matter of seconds/minutes. The next Leightronix timesync at 11:30AM would then get the time from Cablecast's B timesync program. Again, this is a smaller time "tug-of-war" between two programs on the Cablecast machine.

Now, I'm going to agree with many of your thoughts right now that "Isn't atomic time globally precice? What does the time-sync source matter?" Unfortunately this isn't true, varied time sources can be off by as little as a few seconds to as much as a few minutes. Silly, I know.

So what can be syncing time on your machine? The first place to check is inside System Settings in FrontDoor, the Time Sync menu in there will let you know if the Tightrope Timesync is running, the Windows Timesync via Tightrope (on Versions FrontDoor 4.2 and up I believe.) or if Tightrope isn't handling TimeSync at all. Additionally, Windows XP has a Timesync feature if you double click on the clock in the lower-right and open the third tab. However the XP timesync only goes out once a week I believe. There can also be third-party programs such as AboutTime that could be installed.

A final thing to note is that if you've installed your Tightrope systems on a domain within your facility, Windows will automatically take its time from the domain controller. This can obviously setup even ANOTHER "tug-of-war" scenario between the local timesync and the domain timesync.

Now, add in another factor of what time live programming is coming in via satellite compared to your current timesync, and it's easy to see why we've all had some headaches over this.

Chad Gartner
Production/Tech Support
Tightrope Media Systems