CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

[g_remlin]

02:09.0 Multimedia controller: Philips Semiconductors SAA7146 (rev 01)
         Subsystem: Technotrend Systemtechnik GmbH 
Technotrend-Budget/Hauppauge WinTV-NOVA-T DVB card
         Flags: bus master, medium devsel, latency 32, IRQ 17
         Memory at e3001000 (32-bit, non-prefetchable) [size=512]
         Kernel driver in use: budget dvb
         Kernel modules: budget

Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

[BOUWSMA Barry]

Howdy.

I'm afraid that your posting is horribly unclear, with the
apparently important information present in the Subject: header,
as such:

``Subject : Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K,
          Guard 1/4, fails to tune\demux''

I'm going to go out on a limb and ass-u-me that you are writing
to ask about the DVB-H multiplex which is broadcast by SBC on
several different allocated SFN frequencies throughout
Confœderatio Helvetica.  The DVB-T services use a more 
conventional FEC of 5/6 in a denser network of transmitters.

Note that these frequencies are partly re-used in areas where it
is possible to receive simultaneously the out-of-area DVB-T
signals on the same frequency, which renders both impossible to
receive, in spite of a healthy signal strength.  I don't know if
this might affect you.

Not only is this multiplex sent in DVB-H standard, but it is
also a subscription service.  Therefore at best you can read the
PIDs corresponding to the various services, but you aren't going
to be able to watch anything, as different utilities may come to
terms with the datastreams in different ways.  Most Linux 
utilities likely don't know anything of the DVB-H parsing needed
for this service.

Note that I want to verify that this multiplex uses the more
robust QAM16 along with 1/2 FEC rather than the QAM64 you have
given, in order to permit best operation in diverse terrain,
but I can't find my parse results from the datastream amongst
my active disks.  In any case, you can try this tuning option
to see if you get a lock.

In order to receive these broadcasts, you will need to be a
subscriber to this service -- I suggest that you get in touch
with your nearest Swisscom to point you at the provider, though
Sunrise or Orange or anyone else can probably point you to the
provider of this service, who is unknown to me.  I doubt you
will achieve any Linux-based satisfaction here.

If this is not that to which you refer, then please re-formulate
your question in a less ambiguous and more geographically-specific
way, and sorry that I've wasted your time.


thanks,
barry bouwsma


On Fri, 20 Nov 2009, g_remlin wrote:

> 02:09.0 Multimedia controller: Philips Semiconductors SAA7146 (rev 01)
>         Subsystem: Technotrend Systemtechnik GmbH Technotrend-Budget/Hauppauge
> WinTV-NOVA-T DVB card
>         Flags: bus master, medium devsel, latency 32, IRQ 17
>         Memory at e3001000 (32-bit, non-prefetchable) [size=512]
>         Kernel driver in use: budget dvb
>         Kernel modules: budget
> 

Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

[g_remlin]

Hi Barry, thanks for taking the time to reply (my previous more 
informative post was ignored).

This is the Terrestrial transmission standard being rolled out across 
the UK, I live in one of the first areas to be upgraded to the new 
standard. Since the change, my DVB-T PCI card will no longer tune 
(despite the signal level being indicated as OK in Kaffeine). I have 
confirmed the card does work correctly under Windows XP with the 
original card software, so it does not appear to be a hardware issue. I 
have tried numerous apps and various kernels, all without success. Any 
guidance as to what to try next, be it how to gather info for a bug 
report, or even a solution :), would be greatly appreciated.

Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

[BOUWSMA Barry]

On Sat, 21 Nov 2009, g_remlin wrote:

> Hi Barry, thanks for taking the time to reply (my previous more informative

Happy to have helped, even though I didn't help.


> This is the Terrestrial transmission standard being rolled out across the UK,

Ah.  I assumed `CH' referred to the country, and the FEC of 1/2
being that used for a robust yet low-bandwidth signal.

Actually, there are a couple steps to the DSO in the UK, with the
introduction in less than two weeks of the DVB-T2 standard at a
few places, to allow HD broadcasts with some 36 or so Mbit/sec.

This introduction will be taking place without any consumer
equipment until next year, and cannot be received by existing
hardware, as has been asked a few times on these lists.  In
the areas where this happens (apart from places like Crystal
Palace) this is happening by converting one multiplex from
DVB-T to -T2.

You probably are referring to the other part of DSO, which has
meant the conversion from 2k to 8k transmission mode, and the
use of 64QAM modulation.


> I live in one of the first areas to be upgraded to the new standard. Since the
> change, my DVB-T PCI card will no longer tune (despite the signal level being

Once again I'll point out what in your Subject: is likely wrong,
as these are not the values I know to be used in the UK:
``Subject : Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K,
          Guard 1/4, fails to tune\demux''

First off, the 1/2 FEC isn't used as that is used for a robust
signal, as one would want from Handy-TV (DVB-H), and in the UK
with its history of over-the-air broadcasting and rooftop aerials
means that 2/3 and 3/4 are what I see listed (although the data
I'm looking at appears to be pre-8k switchover).

Also, the guard interval would not be 1/4 as the UK makes use of
MFN frequencies, and this appears reflected in the value of 1/32
listed in the old data.

You might try to re-scan with the above values corrected, if this
would be a reason why you can't lock onto a signal.


thanks,
barry bouwsma

Re: CH???, Bandwidth 8MHz, Fec_Hi 1/2, Modulation QAM64, Mode 8K, Guard 1/4, fails to tune\demux

[g_remlin]

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Hi Barry, thanks again, I understood that reply.
I got the Fec/Guard values I was using from the Windows XP app display, 
so am not surprised they are wrong :). Tried your suggestions, but no 
success. I have googled another user who has had success using a 
"switched over" transmitter similar to my local transmitter 
(http://www.dcglug.org.uk/archive/2009/09/msg00538.html), but is not 
using the same modules as me (saa7146, l64781). I have attached the 
tuning information from the Windows XP app in case you are interested.
Not knowing what I am talking about - would the l64781 debug output help ?

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