[mythtv-users] known issues related to DVB-T in Australia (was: Channel tuning broken in 0.24)
Nick Rout
nick.rout at gmail.com
Thu Jun 7 06:20:24 UTC 2012
On Thu, Jun 7, 2012 at 1:23 PM, Igor Cicimov <icicimov at gmail.com> wrote:
> On Thu, Jun 7, 2012 at 11:16 AM, Igor Cicimov <icicimov at gmail.com> wrote:
>>
>> On Thu, Jun 7, 2012 at 10:59 AM, Igor Cicimov <icicimov at gmail.com> wrote:
>>>
>>> On Thu, Jun 7, 2012 at 9:39 AM, Igor Cicimov <icicimov at gmail.com> wrote:
>>>>
>>>> On Wed, Jun 6, 2012 at 8:22 PM, Vincent McIntyre
>>>> <vincent.mcintyre at gmail.com> wrote:
>>>>>
>>>>> curiosity got the better of me...
>>>>>
>>>>>
>>>>> http://git.linuxtv.org/media_tree.git/commitdiff/f0ef7c88ca919912011593d2392a59c2fde04748?hp=4911085fa3342d2ccb04f84c2987305b86785ebf
>>>>>
>>>>> Perhaps this module needs checking for issues like the one in
>>>>> tuners-xc2028.c?
>>>>>
>>>>> Might be worth trying to load the driver module with the debug
>>>>> parameter turned on
>>>>> and doing a scan?
>>>>> _______________________________________________
>>>>> mythtv-users mailing list
>>>>> mythtv-users at mythtv.org
>>>>> http://www.mythtv.org/mailman/listinfo/mythtv-users
>>>>
>>>>
>>>>
>>>> Hi Vincent,
>>>>
>>>> Thanks for your input. I believe that Leadtek card I use is based on
>>>> cx2388x chip. This is the l4v support page and the card, pay attention to
>>>> revision J detail, is listed as card 82:
>>>>
>>>>
>>>> http://git.linuxtv.org/media_tree.git/blob/HEAD:/Documentation/video4linux/CARDLIST.cx88#l83
>>>>
>>>> and is being properly recognized as card=82 in the kernel module during
>>>> boot.
>>>>
>>>> From the driver change log you sent me we can see some work was done for
>>>> DTV2000H Plus card support which is different one from the one I have.
>>>>
>>>> To answer the question about channel 9 ... It's really a roulet with
>>>> this channel, sometimes its terrible and locks the frontend same as GO and
>>>> GEM but sometimes liveTV is fine. But the recordings are always horrible ...
>>>> go figure. I noticed that 7 is also bad but 7two is perfect. For the rest of
>>>> them the LiveTV works fine and the recording are good quality.
>>>>
>>>> Someone, I think it was Nick, asked me about channel tuning setup in the
>>>> backend more specifically about fast channel tuning. I had that option set
>>>> to "Always" but had to switch it to "Never" because of the tuning issues I
>>>> have. This way I can skip the channels I know are broken without freezing
>>>> the frontend in case of auto channel change.
>>>>
>>>> It really sucks that, as Karl says at the beginning of the thread,
>>>> channel import doesn't work properly too for Australia. Can someone confirm
>>>> that this is being fixed? I really can't see any more options for me except
>>>> for channel import after dvbscan.
>>>>
>>>> I have an old channels.conf in Mplayer from 13/09/2008 so will try that
>>>> one with Mplayer/xine first before I create a new one.
>>>>
>>>> Thanks,
>>>> Igor
>>>
>>>
>>>
>>> Ok, I shutdown the mythbackend and did a scan. This is the result of the
>>> initial scan with w_scan (with terrestrial TV channels option only):
>>>
>>> $ cat initial-tuning-data.txt
>>>
>>> #------------------------------------------------------------------------------
>>> # file automatically generated by w_scan
>>> # (http://wirbel.htpc-forum.de/w_scan/index2.html)
>>> #! <w_scan> 20091230 1 0 OFDM AU </w_scan>
>>>
>>> #------------------------------------------------------------------------------
>>> # location and provider: <add description here>
>>> # date (yyyy-mm-dd) : 2012-06-07
>>> # provided by (opt) : <your name or email here>
>>> #
>>> # T[2] <freq> <bw> <fec_hi> <fec_lo> <mod> <tm> <guard> <hi> [# comment]
>>>
>>> #------------------------------------------------------------------------------
>>> T 177500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE # Seven Network
>>> T 219500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE # Network TEN
>>> T 226500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE # ABC Sydney
>>> T 536625000 7MHz 2/3 NONE QPSK 8k 1/8 NONE # CTV
>>> T 571500000 7MHz 2/3 NONE QAM64 8k 1/8 NONE # SBS Sydney
>>>
>>>
>>> And for comparison this is what I have in MythTV database:
>>>
>>> mysql> select mplexid,sourceid,transportid,networkid,frequency,sistandard
>>> from dtv_multiplex;
>>> +---------+----------+-------------+-----------+-----------+------------+
>>> | mplexid | sourceid | transportid | networkid | frequency | sistandard |
>>> +---------+----------+-------------+-----------+-----------+------------+
>>> | 1 | 1 | 1538 | 4116 | 219500000 | dvb |
>>> | 2 | 1 | 2 | 57 | 536500000 |
>>> dvb |
>>> | 12 | 1 | 768 | 12802 | 571500000 | dvb |
>>> | 11 | 1 | 545 | 4112 | 226500000 | dvb
>>> |
>>> | 10 | 1 | 1056 | 4114 | 191500000 | dvb |
>>> | 9 | 1 | 1282 | 4115 | 177500000 | dvb
>>> |
>>> +---------+----------+-------------+-----------+-----------+------------+
>>>
>>> Looks like Myth did even better tuning job than w_scan and found one more
>>> transponder with frequency of 191500000 :). Maybe that's the channel9/GO/GEM
>>> carrier?
>>>
>>> After using scan to turn this initial file to channels.conf this is what
>>> I get:
>>>
>>>
>>> $ cat .tzap/channels.conf
>>> 7
>>> Digital:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:513:514:1312
>>> 7 Digital
>>> 1:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:513:514:1313
>>>
>>> 7TWO:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:545:546:1314
>>>
>>> 7mate:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:561:0:1315
>>> 7
>>> Digital:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:513:514:1316
>>>
>>> TV4ME:177500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_3_4:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:625:626:1319
>>>
>>> ONE:219500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:514:0:1569
>>> TEN
>>> Digital:219500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:512:650:1573
>>>
>>> ONE:219500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:514:0:1575
>>>
>>> ELEVEN:219500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:516:681:1576
>>> ABC News
>>> 24:226500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:2314:0:544
>>>
>>> ABC1:226500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:512:650:545
>>> ABC2 /
>>> ABC4:226500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:2307:2308:546
>>>
>>> ABC1:226500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:512:650:547
>>>
>>> ABC3:226500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_3_4:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_16:HIERARCHY_NONE:2311:2312:548
>>>
>>> TVS:536625000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QPSK:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:100:101:44
>>> SBS
>>> ONE:571500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:161:81:769
>>> SBS
>>> TWO:571500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:162:83:770
>>> SBS
>>> 3:571500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:161:81:772
>>> SBS
>>> 4:571500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:161:81:773
>>> SBS
>>> HD:571500000:INVERSION_AUTO:BANDWIDTH_7_MHZ:FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_8:HIERARCHY_NONE:102:103:774
>>>
>>> so no channel9, GO and GEM as we can see.
>>>
>>> From this I would say it is obvious that the tuning problem is not in
>>> MythTV since both scans yield practically same results.. If there is an
>>> issue with the frequency offset in AUS then both w_scan and Myth behave same
>>> and fail to lock to the offset frequency of +125KHz of our carriers.
>>>
>>> What I'm going to do next is add the channel9 frequencies that Vincent
>>> posted into my channel.conf and check if Mplayer can tune to this channels
>>> at all.
>>>
>>> Igor
>>>
>>>
>>>
>>
>> Ok, after adding the channel9 frequencies I tried Mplayer and it crashed
>> when trying to tune to channel9. So same problem as MythTV.
>>
>> CONCLUSION: For some reason my card can't tune to channel9 frequency any
>> more and probably this is related to the dvb driver in Lucid. I didn't have
>> any issues at all with these channels on 8.04 and Myth 0.20. I'll do some
>> investigation and try to find the exact reason. Maybe building the latest
>> v4l modules from git will help.
>>
>> Igor
>
>
> Just for completnes, this is my dtv_multiplex table (after adding additional
> 125KHz to the frequencies as suggested by Karl):
>
>
> mysql> select mplexid,sourceid,transportid,networkid,frequency,sistandard
> from dtv_multiplex;
> +---------+----------+-------------+-----------+-----------+------------+
> | mplexid | sourceid | transportid | networkid | frequency | sistandard |
> +---------+----------+-------------+-----------+-----------+------------+
> | 1 | 1 | 1538 | 4116 | 219625000 | dvb |
> | 2 | 1 | 2 | 57 | 536625000 | dvb
> |
> | 12 | 1 | 768 | 12802 | 571625000 | dvb |
> | 11 | 1 | 545 | 4112 | 226625000 | dvb |
> | 10 | 1 | 1056 | 4114 | 191625000 | dvb |
> | 9 | 1 | 1282 | 4115 | 177625000 | dvb |
> +---------+----------+-------------+-----------+-----------+------------+
> 6 rows in set (0.00 sec)
>
> Would love to see what other Aussies have in their multiplex table.
>
> Igor
>
Sorry I have not analysed the situation in this long lists of posts
enough or I would be able to answer this myself:
Is the tuning problem with higher frequencies? I have seen it said on
this list or some myth forum that the higher frequencies are harder to
tune.
Sorry that's not a solution, but it may point to a problem...
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