Re: [linux-dvb] new DVB-T initial tuning for fr-nantes

[Christophe Thommeret <hftom@free.fr>]

Le mardi 18 mai 2010 16:25:56, BOUWSMA Barry a écrit :
> On wto (wtorek) 18.maj (maj) 2010, 15:05:00, matpic wrote:
> 
> Salut!
> 
> > hello
> > As from today (18/05/2010) there is new frequency since analogic signal
> > is stopped and is now only numeric.
> > guard-interval has to be set to AUTO or scan find anything
> > 
> >  (1/32, 1/16, 1/8 ,1/4 doesn't work)
> 
> I do not have the CSA data at hand, but I understand that
> presently use is made of single transmitter sites, in a MFN
> (Multi-Frequency Network) and thus a guard interval of 1/32 should
> be correct.
> 
> (I understand though that some filler transmitters may be in
> planning so that a small SFN may be put in service, but I am
> not clear as to these details...  I must research this.)
> 
> > #same frequency + offset 167000000 for some hardware DVB-T tuner
> 
> It was my understanding that the different offsets above or
> below the nominal centre frequency is a result of mixed digital
> and legacy analogue services co-broadcasting, in order to avoid
> interference with adjacent channels.
> 
> So I am wondering whether, in the absence of local analogue
> services, this offset is no longer employed?
> 
> I am afraid that I am not following the conversion to TNT so
> closely to know if a whole geographic region, in this case the
> Loire, is having the remaining analogue services shut down all
> at once, or if it is being done on a site-by-site basis, with
> the potential for interference to a more remote but still
> operational analogue transmitter.
> 
> In any case, all but one of the new frequencies appear to be
> very different from the ones previously used before today.
> 
> 
> Merci, for reporting this change!
> 
> barry bouwsma

All analogic services are all closed at once.
I guess the "offset" is there to help some (buggy?) devices, like cinergy T2, 
not to reflect a real frequency offset.

-- 
Christophe Thommeret