DVB-S transponder time differences

Forums › Freeview (DVB-T/DVB-S) › DVB-S transponder time differences

RunningMan

9184 posts

Uber Geek
+1 received by user: 4834

#119302 27-May-2013 17:42

I was recently troubleshooting a device that suddenly started cutting a minute or so off the start of some recordings.

There appears to be about a 2 minute time difference between the 2 Freeview transponders 12456 and 12483.

The time broadcast by 12483 seems to be more or less accurate, with the time broadcast by 12456 about 2 minutes slow.

Can anyone else confirm this behaviour?

Who controls the transponder time - Freeview, or the broadcaster?

bda

10 posts

Wannabe Geek
+1 received by user: 1

#826773 28-May-2013 07:44

Yes I discovered the same thing after missing the start of recordings.

knoydart

904 posts

Ultimate Geek
+1 received by user: 154

Trusted

#826806 28-May-2013 09:21

The satellites are dumb pipes so it will be Freeview who collates the information (and programs) at the head end and sends to (I think) Kordia for uplink at Avalon in the Hutt Valley. The boxes at the headend will prob need adjusting.

openmedia

3449 posts

Uber Geek
+1 received by user: 878

Trusted

#826819 28-May-2013 09:50

RunningMan: I was recently troubleshooting a device that suddenly started cutting a minute or so off the start of some recordings.

There appears to be about a 2 minute time difference between the 2 Freeview transponders 12456 and 12483.

The time broadcast by 12483 seems to be more or less accurate, with the time broadcast by 12456 about 2 minutes slow.

Can anyone else confirm this behaviour?

Who controls the transponder time - Freeview, or the broadcaster?

Just want to confirm. You are talking about the DVB-S embedded time signal rather than programs appear to be off by 2 minutes?

You should use NTP as a time source as DVB based time signals are seldom accurate. For any recordings I always start 90 seconds or more early, and for most shows overrun by 5 minutes. If the show is something Live - eg X Factor NZ - the allow upto 30 minutes.

Generally known online as OpenMedia, now working for Red Hat APAC as a Technology Evangelist and Portfolio Architect. Still playing with MythTV and digital media on the side.

RunningMan

9184 posts

Uber Geek
+1 received by user: 4834

#827166 28-May-2013 16:23

openmedia:Just want to confirm. You are talking about the DVB-S embedded time signal rather than programs appear to be off by 2 minutes?

Correct - not talking about whether or not the broadcaster is sticking to the schedule, but that the embedded time is wrong.

If you flick between channels on different transponders, say TV2 & TV3, then the time changes by about 2 minutes as you move back and forth.

RunningMan

9184 posts

Uber Geek
+1 received by user: 4834

#828293 30-May-2013 13:58

Well, for reasons not known to me, this appears to be resolved now, with the transponder embedded time being more or less the same across and transponders, and accurate.

Presumably someone changed the time somewhere, but we may never know!

RunningMan

9184 posts

Uber Geek
+1 received by user: 4834

#847206 29-Jun-2013 18:30

Well, a similar problem seems to be back. Embedded time on 12483 seems accurate, with 12456 running about 2 minutes fast this time.