Windows Time Sync vs. Network stations

[brendonrd]

I constantly have the problem where the built in Windows time Sync is a few min out from the stations and I need to disable then constantly adjust the system time to match the broadcasts. Is there a network time source (NTP) with the correct station time? OR Could IceTV publish a NTP server sync'ed with the station broadcast?

Just an idea....

[Mark]

There should not be a problem with synchonisation between station broadcasts and Windows time, if Internet time sync is working properly.  The Internet time function in Windows is based upon the Network Time Protocol (NTP), which is ultimately referenced to one of a relatively small number of "stratum-1" time servers around the world which maintain extremely accurate clocks.  Worst-case performance for NTP these days should set your clock to within about 100 milliseconds of the correct time.  

My observation of the times transmitted with the networks digital broadcasts is that they are accurate.  I am running two recorders: Windows Vista MCE with IceTV and Internet time synchronisation, and a Topfield PVR (without IceTV EPG) which syncs to the incoming broadcast time.  Despite having read some reports of temporary anomalies in broadcast times throwing off the Topfield clock, I have never seen this phenomenon myself.  Both recorders keep perfect and consistent time (to the level of accuracy that I can manually observe).  A few minutes' discrepancy is a lot, and suggests something wrong at your end.

I have no experience with Windows 7, but you might want to check that your internet time sync is working properly.  When your system time seems to be out, open the date and time properties panel, and go to the "Internet time" tab, then go to "Change settings".  If the time server is set to "time.microsoft.com" you might want to change it to use a more local source.  Your ISP probably runs a time server (Optus provides time.optusnet.com.au, for example).  This shouldn't make much difference, because NTP is designed to compensate for network delay and jitter, but you never know.  Then click "Update now" to see if this corrects the time.  If so, then the problem may be that you local system clock suffers from excessive drift.  By default, the Windows time sync runs only once per week, so if your clock gains (for example) one minute per day, it will be out by seven minutes by the time it is again synchronised.

If clock drift is a problem, then the proper solution is to get it fixed/replaced -- your PC clock should not be so inaccurate!  

However, as a temporary fix you can alter the time sync frequency via the Registry (at least in Win 2000/XP/Vista -- hopefully this is the same in Win7).  Navigate to the following key in the Registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient

Right click on 'SpecialPollInterval' in the right hand column and select Modify>Decimal.  The decimal number is in seconds.  For example, "3600" will cause your system to synchronise every hour.  Then go back and "Update now" again, to shift onto the new schedule.

As always, before messing with the Registry it is wise to backup or create a restore point before proceeding.

[tonymy01]

But Mark, where are you located?  Some dodgy broadcasters don't know their system very well (I was going to say something else related to human anatomy, but decided to leave that one out  :) ), and often do silly things like adjust the GMT clock instead of the localtime/GMT offset when DST kicks in, or simply don't setup the NTP properly on their broadcast systems.  A few years ago, even in Sydney, Nein was 15minutes out for about a week!
But now in Sydney I notice it is very good, they have finally got their act together here, regionals may not be so good in this area yet.
Regards

[Mark]

But Mark, where are you located?  Some dodgy broadcasters don't know their system very well (I was going to say something else related to human anatomy, but decided to leave that one out  :) ), and often do silly things like adjust the GMT clock instead of the localtime/GMT offset when DST kicks in, or simply don't setup the NTP properly on their broadcast systems.  A few years ago, even in Sydney, Nein was 15minutes out for about a week!
But now in Sydney I notice it is very good, they have finally got their act together here, regionals may not be so good in this area yet.
Regards

I'm in Melbourne.  But if the problem is that individual broadcasters can't set their clocks correctly, then there is no viable solution.  An NTP server synced to one dodgy station would still be wrong for all the others!  The best you could do is to ensure that your PC clock is correct, and then ignore anything coming in on the digital broadcasts.  I understand that Windows 7 Media Center can read the in-band EPG data, but have not seen it myself, and don't know whether it also tries to make some use of in-band time information, or if this is part of the problem here.

Maybe if the original poster could elaborate a little on the problem -- how do the PC time and the broadcast times compare with the actual time (i.e. as obtained by calling 1194)?

[brendonrd]

Hey guys,

I should have specified originally. I'm in Brisbane Metro, an mainly have problems with Channels 7, Ten or ABC. I tried running the device to time sync with the default windows.microsoft.com but got in trouble from the wife because she was missing the end of all her shows.

I have recently changed the CPU & MB, and been running several builds of Windows 7, all with the same problem.

+15 Min record time with 4 tuners was no problem. Now with it down to 2 min on the beta, I get in trouble again. :(

[Mark]

Sounds like your problem is not time setting, just that Aus TV channels do not run to schedule!  Trying to set your clock to the wrong time is not a solution to this problem.

I have been led to understand that Windows 7 Media Center lets you set higher padding values than previous versions, but initial beta versions of the IceTV Interactive app limit you to 2mins.  IceTV are trying to fix this -- see the main topic "Beta IceTV Interactive for Windows 7 available" in the "Interactive on Windows 7" discussion forum for more info.