Opened 6 years ago

Last modified 5 years ago

#11427 new Bug Report - General

LiveTV/Recording doesn't work with CBand LNBs from 0.25 onwards

Reported by: nick.marshall@… Owned by:
Priority: minor Milestone: unknown
Component: MythTV - General Version: 0.26-fixes
Severity: medium Keywords: cband, livetv, fail, myth
Cc: Ticket locked: no

Description

When using mythtv 0.25 or 0.26 if you follow through all of the steps in setting it up with a ku band LNB myth will work fine and all epg data will be populated. Works fine for mythtv 0.25/0.26.

If you do the same thing with a cband lnb it will locate the channels and add them to the database as expected but when trying to watch tv or record tv it will be unable to.

Recording and watching tv from a cband lnb does work in 0.24 however.

The issue is nearly identical to the one here: http://www.mentby.com/dg-mailing-list/

Cards tested on: hauppage nova-s plus, hauppage nexus-s

OS used: Mythbuntu 12.04, Centos 6.3

Issue also occurs on multiple different lnbs and satellites. Signal strength (90-99%)

mythbackend -v siparser,eit,channel produces this:

2013-02-27 12:02:32.300751 I  DVBChan(1:/dev/dvb/adapter0/frontend0): Opening DVB channel
2013-02-27 12:02:32.307593 I  ChannelBase(2): Input #2: 'DVBInput' schan(401) sourceid(1) ccid(2)
2013-02-27 12:02:32.307647 I  ChannelBase(2): Current Input #2: 'DVBInput'
2013-02-27 12:02:32.309835 I  DTVChan(/dev/dvb/adapter0/frontend0): SetChannelByString(401):
2013-02-27 12:02:32.316999 I  DTVChan(/dev/dvb/adapter0/frontend0): SetChannelByString(401): failure
2013-02-27 12:02:32.317066 I  ChannelBase(2): Looking for startchannel '401' on input 'DVBInput'
2013-02-27 12:02:32.324487 I  ChannelBase(2): Found startchannel '401' on input 'DVBInput'
2013-02-27 12:02:32.337698 I  Found 0 distinct programid authorities

and when it tries to get EIT data

2013-02-27 12:03:35.314224 I  EITScanner (1): StartActiveScan called with 1 multiplexes
2013-02-27 12:03:35.599338 I  TVRec(1): SetChannel(401) -- begin
2013-02-27 12:03:35.601670 I  DVBChan(1:/dev/dvb/adapter0/frontend0): Opening DVB channel
2013-02-27 12:03:35.601731 I  DTVChan(/dev/dvb/adapter0/frontend0): SetChannelByString(401):
2013-02-27 12:03:35.609460 I  DTVChan(/dev/dvb/adapter0/frontend0): SetChannelByString(401): failure
2013-02-27 12:03:35.609520 E  TVRec(1): Failed to set channel to 401. Reverting to kState_None
2013-02-27 12:03:35.610040 I  TVRec(1): SetChannel(401) -- end
2013-02-27 12:03:35.610086 I  EITScanner (1): Now looking for EIT data on multiplex of channel 401

And the frontend when trying to watch tv:

2013-02-27 12:06:04.507525 N  TV: Spawning LiveTV Recorder -- begin
2013-02-27 12:06:04.561636 N  TV: Spawning LiveTV Recorder -- end
2013-02-27 12:06:04.564137 E  GetEntryAt(-1) failed.
2013-02-27 12:06:04.564199 E  It appears that your backend may be misconfigured.  Check your backend logs to determine whether your capture cards, lineups, channels, or storage configuration are reporting errors.  This issue is commonly caused by failing to complete all setup steps properly.  You may wish to review the documentation for mythtv-setup.
2013-02-27 12:06:04.581668 E  EntryToProgram(0@Thu Jan 1 12:00:00 1970) failed to get pginfo
2013-02-27 12:06:04.581755 E  TV: HandleStateChange(): LiveTV not successfully started
2013-02-27 12:06:04.584038 E  TV: LiveTV not successfully started
2013-02-27 12:06:04.637334 I  TV: Main UI disabled.

Backend from the same time:

2013-02-27 12:06:04.513256 I [2073/2083] TVRecEvent tv_rec.cpp:1030 (HandleStateChange) - TVRec(1): Changing from None to WatchingLiveTV
2013-02-27 12:06:04.539601 I [2073/2083] TVRecEvent tv_rec.cpp:3503 (TuningCheckForHWChange) - TVRec(1): HW Tuner: 1->1
2013-02-27 12:06:04.557845 E [2073/2083] TVRecEvent tv_rec.cpp:3689 (TuningFrequency) - TVRec(1): Failed to set channel to 401. Reverting to kState_None
2013-02-27 12:06:04.557977 I [2073/2083] TVRecEvent tv_rec.cpp:1030 (HandleStateChange) - TVRec(1): Changing from WatchingLiveTV to None
2013-02-27 12:08:34.658128 E [2073/2083] TVRecEvent tv_rec.cpp:3689 (TuningFrequency) - TVRec(1): Failed to set channel to 401. Reverting to kState_None

Looks like the frontend failures are due to not being able to tune to the channel after running the mythtv-setup.

note- all of this works fine for 0.24 just the newer versions don't work.

Also in New Zealand if that's any use.

Change History (2)

comment:1 Changed 5 years ago by r.w.grimmett@…

I have the same issue with C band LNBs. Version 0.24 works fine, tvheadend works fine also. MythTV 0.25 and 0.26 work perfectly with my Ku band LNB's .

The only difference that I can see between Ku and C band is that Ku is a much higher frequency.

I wonder if some how the frequency table that is being made with mythtv setup or the method of reading the frequency when you request a channel is the problem when trying to get a lock on a C band transponder ?

I wonder are there any tools that can be used to watch what the dvb-s cards are actually doing ?

i.e log the frequency that was requested of the card ?

I am in Australia and there are a lot of people with english as a 2nd language here with C band dishes who could potentially be mythtv users if this bug was resolved.

A MythTV system is so much better than the cheap and nasty Sat receivers that are typically used for satellite.

comment:2 Changed 5 years ago by t.dobes@…

I'm seeing this problem as well -- exact same symptoms - tested MythTV 0.25, 0.26, and 0.27. Tested both Debian Jessie and MythBuntu? 14.04.1. My old Debian Squeeze install with MythTV 0.24 continues to work fine with the exact same hardware.

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