[linux-dvb] au tuning files
christophpfister at gmail.com
Tue Jun 5 18:56:22 CEST 2007
Am Sonntag, 3. Juni 2007 10:56 schrieb Peter D.:
> I'm taking some things on trust here, so feel free to tell me I am wrong.
> My main source is http://www.dba.org.au/index.asp?sectionID=120
> It says, among other things;
> these parameters may be changed from time to time without warning,
> receivers need to comply with Standards Australia standards AS 4933
> and AS 4599, as well as DVB standards, that say a receiver needs to
> identify and receive all COFDM modes, including hierarchical (see
> below), and
> the receiver should check the Transmission Parameter Signaling (TPS)
> some broadcasters use centre frequency offsets
> I'm not sure how clever that means tuners sold in Australia should be or,
> more importantly, actually are.
> In this post
> http://www.linuxtv.org/pipermail/linux-dvb/2007-May/018262.html John
> offered a tuning file for Australia that was mostly full of "AUTO"s with
> what looks like an entry for every frequency used in Australia. It works
> for me with a Kworld/VStream Xpert card in Melbourne.
> I don't know how much the Australian "standards" vary from international
> standards, but I believe that one or two channels have been moved by a
> Mega Hertz and an extra channel (9A) added. Channel 12 might be non
> too, I don't know.
> Looking through the au-* tuning files and the www.dba.org.au site there are
> some things that are still a mystery to me.
> There seem to be many more transmitters scattered around the country than
> are mentioned in the au-* tuning files.
There are two possible reasons for this:
- People submitted stuff for regions where they live, so certain areas aren't
covered at all.
- Single-frequency network; multiple transmitters use the same frequency (and
also the same modulation parameters), so you don't need a scan file for each
> The www.dba.org.au site only lists a single FEC for each group of channels,
> while the tuning files have a fec_hi and a fec_lo. In many files that is
> given as a fraction and a "NONE", sometimes as two fractions, usually the
> same fraction - sometimes as different ones.
> Is the fec_low value used? Only valid sometimes? Should it be "AUTO",
> "NONE", the same as fec_hi, or is it an independent variable?
If no hierarchy is involved, it doesn't matter. Ideally it should be set to
NONE in that case, but this doesn't happen very often.
> The big problem is that *most* of the channel 7 transmitters have changed
> their guard interval.
> The changes that I am offering here seem to be improvements, but I can
> only test Melbourne stuff.
> au-Perth and au-Melbourne have recently changed to have the new ch7 GI.
> The files attached are;
> A generic Australian file, au-auto, from John.
> au-Adelaide, new ch7 GI
> au-Cairns, new ch7 GI
> au-Canberra-Black-Mt, new Prime FEC and GI
> au-Darwin, new Southern Cross FEC and GI, new ch9 FEC and GI
> au-Melbourne-Upway, new ch7 GI
> au-MidNorthCoast, lots of changes
> au-SpencerGulf, new SBS FEC
> au-Sydney_Kings_Cross, new ch7 GI
> au-Townsville, new ch7 GI
> There are other au-*tuning files that I am not offering changes for.
Thanks for your effort! I'll deal with them soon - maybe there's also the
possibility to create those files by a script so updates can be done more
More information about the linux-dvb