[mythtv-users] BBC HD sat mux transport parameter change...

Andy Sheen sheen.andy at googlemail.com
Wed Sep 5 22:16:28 UTC 2012

Robert Longbottom wrote on Wed 05 Sep at 22:50 UK time
> On 05/09/2012 22:28, Andy Sheen wrote:
>> Hi all,
>> Any one with any clues about this. It must be an easy answer for those
>> in the know (at least for what I can do by messing in the database).
>> Thanks
>> Andy
>> On 4 September 2012 23:26, Andy Sheen <sheen.andy at googlemail.com
>> <mailto:sheen.andy at googlemail.com>> wrote:
>>     Hi all,
>>     So Auntie Beeb are going to be playing with their parameters for
>> the BBC
>>     HD/BBC One HD stream on the 27th September.
>>     According to:
>> http://www.bbc.co.uk/blogs/aboutthebbc/2012/09/blah.shtml
>>     They will be changing the transponder from:
>>     10,847MHz, Vertical, DVB-S2, QPSK, 23M, 8/9 FEC
>>     to:
>>     10,847MHz, Vertical, DVB-S2, 8PSK, 23M, 2/3 FEC
>>     Given the ONLY changes are QPSK -> 8PSK and 8/9 -> 2/3 FEC, this
>> seems
>>     like a change I'm willing to do via playing with the database
>> directly
>>     (backup/yes, I know I could kill the system, here might be
>> dragons, we
>>     don't recommend it all noted ;)). So... FEC 8/9 -> 2/3 is easy
>> enough to
>>     do, but what do I do about the modulation field in dtv_multiplex?
>> Change
>>     qpsk to 8psk, leave it as qpsk, or something else?
>>     Also, I assume that my cards/drivers/MythTV have support for 8PSK in
>>     them - googling would lead me to believe they are supported. I'm
>> running
>>     a Tevii S480 and Hauppauge WinTV-HVR400 under Ubuntu 12.04LTS with
>>     mythbackend version: fixes/0.25 [v0.25.1-49-g65913e7].
>>     Is there any way to check this before the date? Should I just
>> relax? I'm
>>     paranoid about this as I work with embedded sat systems and I know
>>     making assumptions about what tuners do and don't support in their
>>     drivers is dangerous....
>>     Thanks
>>     Andy
> I'll start by saying that I have BBC HD and BBC One HD working on my
> system.

I too, have the two working on my system.
> Have you looked at what settings are actually in your database?
> I've just looked in mine and currently the only "constellation" values I
> have are NULL and qpsk:

I only have QPSK (but I don't have a very big database - I was hoping
someone might have an 8PSK modulation in their database to be able to
say definitively.

> So it looks like I might need to change fec, which as you say is easy.
> As for constellation, it's NULL anyway, which I'm guessing means auto?

Well, if QPSK doesn't work,. I can always try null!!

> Cheers,
> Rob.



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