How to set the time of DOLBY DSS200 server to correct time?

[Leo Enticknap]

Which proves Steve's claim, because the cat745 will run forward between one and two hours a year if left unpowered for the entire time. Unless the projector it's installed in has its card cage powered up 24/7, it is impossible to keep a cat745 within the DCI budget without manual intervention.

[Harold Hallikainen]

The DSP100 was VERY accurate, the CAT862 is reasonably accurate, the CAT745 is less accurate than a sun dial).

Great line about the CAT745! Got me digging into sundials. https://en.wikipedia.org/wiki/Sundial indicates that a heliochronometer is a sundial that corrects for the equation of time resulting in an accuracy within one minute throughout the year. Good enough for KDMs!

[Steve Guttag]

In the DSS line of servers, there are multiple clocks at play. The Secure Clock (DSP100, CAT862 or CAT745) is strictly for KDM times. The only time the server accesses that clock for the show clock is upon boot up. It will FIRST see if the NTP source is there and if not, it then checks the secure clock, if it is there, it will set to that...if the secure clock is not there, then the BIOS clock remains unchanged. The server has always run the shows off of its BIOS clock. If there is a good NTP, then the BIOS clock is updated with the time of the NTP. This is why rebooting a DSS server will reset the show clock, presuming the secure clock was accurate (the DSP100 was VERY accurate, the CAT862 is reasonably accurate, the CAT745 is less accurate than a sun dial). There is a script in the SSH CLI where you can tell the DSS200 to never set the BIOS clock off of the CAT745 (I think that came in 4.9 but it might have been there in later 4.8 versions).

Here is another tidbit. If you have a TMS, like the DSL100 or DSL200. The clock that shows is always the DSL's clock while in TMS mode. However, the show clock remains the individual DSS server's BIOS clock. If you have screens that start early or late compared to the clock showing in the upper-left (via the DSL), then you don't have good NTP and the individual server has drifted.

If a DSS server is drifting wildly on its own (and there isn't a bogus "NTP" source it is referencing on bootup (like a PC used as an NTP source that has no valid NTP), then that is an indication of a BIOS battery that is draining. DSS servers that do wacky things on boot up (or don't boot up properly) can also be due to very low BIOS battery (not quite low enough that the turn on on power resume is forgotten but also not strong enough to boot things up properly).

[Carsten Kurz]

They all use CAT862. If the GUI allows to set the secure clock within DCI ruling - why is it reset after a reboot? I can only assume that there IS a sync to the DSS200 TMSlite master machine still running in the background, even if no NTP is configured on the secure clock adjustment dialog.

[Leo Enticknap]

Do these servers use the cat862 (internal media block) or cat645 (IMB)? If the latter, you can adjust it manually. I will email you the instruction sheet, as it contains login credentials (against forum rules to post).

[Carsten Kurz]

To pick this up - a colleague is operating a few DSS200. Yesterday, he corrected secure time through the GUI, within approx 2min, so, within the DCI allowance.The correction was taken - but after a reboot, the time is wrong again for all servers. According to him, there are no NTP servers configured currently.

I'm waiting for a response as to wether the time is off by the same amount on all servers (that would still hint to some NTP delivering wrong time). As they use a few DSS200, they probably use one as a TMS light Dolby style?

edit: Looks as if all servers are off by the same amount. I told him to try the correction again first on the Master/TMS machine.

[Mike Qu]

Thanks to all replies.
We have a long time close-down in Shanghai where I live, just begin to work,so I make the reply.
Finally,I setup an internet and use a NTP server that offer by Chinese goverment association.All works nice.

[Mark Gulbrandsen]

I just looked up WWV and WWVH, and it says that WWVL gets into Asia. Although it was not location specific. WWVH is located in Hawaii. So it has a better chance of reaching Asia. WWVL is also a VLF signal at about 20KHZ.

[Marcel Birgelen]

He should be able to pick up the NIST signal that's broadcast out of Boulder, CO. I would imagine the Chinese also have their own.

According to NIST itself, China is a little bit outside their coverage zone.

The German based DCF77 is also out of reach. I don't know if China has their own public RF-based time signal, but I guess the Japanese JJY system will at least reach the Eastern parts of China.

[Mark Gulbrandsen]

I don't know about where you are located but here, where I live, I use a time server operated by the U.S. Naval Observatory.
tick.usno.navy.mil or tock.usno.navy.mil (Get it? "tick" and "tock"? )

Your profile says you are in China so my server is probably restricted for you. A time server located in the United States won't do you much good, anyhow. You need to find a time server located in China.

I'm certain that the government of China or some-such public entity operates time servers that you can use where you live.

Every computer, iPhone or other device that I own which can use a time server is set for "tick" or "tock."

Never had a problem getting accurate time in years.

He should be able to pick up the NIST signal that's broadcast out of Boulder, CO. I would imagine the Chinese also have their own.

[Mark Gulbrandsen]

There are situations, where there is no access to a NTP server. I serviced 2 drive ins, and in both, the projectors were controlled locally without any networked connection. One lost it's time frequently, and the solution at the end has been to connect a WiFi bridge, use the operator's smartphone as a source for the NTP, by connecting over wifi to a phone provided hotspot every day at startup. That solved the problem, and the time was kept in sync with actual time.
AS stated by others here, DCI timekeeping relies on true NTP server synchronization.

I service two DI as well, but one has year round internet, so not a problem. The other drive in near Powell, WY has no internet, but one can create a hotspot and run the laptop for an hour or two to sync them up while you are there servicing. So, if I go to that one twice yearly, then the clock is always very close.

[Mattias Mattsson]

If the DSS server (and they all set the same) cannot locate an NTP time source (they default to looking for the DSL show library at 192.168.241.2), they will update off the secure clock (it is possible to defeat this if one has a CAT745 since they are so awful at keeping time).

Interesting. How do you turn off syncing of the system clock to the Cat745 (when no NTP server is available)?

[Marcel Birgelen]

That's pretty cool! I was, just last week, reading about phased emitter arrays and how they can be used for beam steering. It's pretty damned amazing stuff!

Well, GPS is a relatively simple signal... imagine this being done for a broadband Internet connection... I guess that's why Musk is paying about $1500 on top of every StarLink terminal they're selling.

I have had GPS time receivers in my home for over 20 years, mainly because of my interest in clocks, but also to use as a calibration reference.. I am on my third one now, all due to changes in the GPS protocol... the last one due to an existing bug in the day that was sent out by the Satellites. This bug was known to exist and it did not affect all receivers. . All had or have rubidium oscillators in them so I can calibrate electronic gear to a very stable know reference.

We used to have a bunch of these at one of my previous jobs, located in several datacenters throughout the world. From those, we fed our own Stratum 2 NTP servers, which were then used by all the different clients. If you're stuck somewhere without reliable Internet access, there are cheap alternatives nowadays, like a RasPi-based NTP server, that syncs with GPS.

Nowadays, my primary time reference is provided by this guy, I mean, he runs several cesium atomic clocks, some kept on UTC and others on TAI time. Personally, I'd really love to switch all machines to TAI time to get rid of those damn leap seconds, which have often caused havoc in complex computing systems that require precision timing and don't like to see the same timestamp twice...

[Stefan Scholz]

There are situations, where there is no access to a NTP server. I serviced 2 drive ins, and in both, the projectors were controlled locally without any networked connection. One lost it's time frequently, and the solution at the end has been to connect a WiFi bridge, use the operator's smartphone as a source for the NTP, by connecting over wifi to a phone provided hotspot every day at startup. That solved the problem, and the time was kept in sync with actual time.
AS stated by others here, DCI timekeeping relies on true NTP server synchronization.

[Randy Stankey]

Years ago, I knew somebody who pulled apart a smoke detector. I was like, "Dude! That's Americium in there! It's radioactive for 10,000 years!"

That's when I conceived the coffee can idea. It was either that or call the fire department or other authorities which might set off all kinds of alarm bells.

The penny embedded in the concrete is there to give anybody who finds it, in the future, some idea of how long it had been there.

I don't remember how radioactive Americium really is or what type or radiation it emits. I suppose I could look it up.
The whole reason for the exercise was because if the authorities found out, there would be questions asked and cleanup costs to pay.

Americium really isn't THAT dangerous or else they wouldn't put it in smoke detectors for sale to the public.

I just wanted to make the problem "go away" as quietly and as safely as I knew how.