[mythtv-users] SVN 0.19-fixes Ticket#1552 and the Nova-T DVB-T

[Doug Scoular]

Hi Andrew,

Andrew wrote:
> Anyone with a Nova-T DVB-T card and running 0.19-fixes applied
> changesets 10127/8/9 and 10132 yet?
> See http://svn.mythtv.org/trac/ticket/1552
>
> Does this speed up or slow down tuning?
>
>   
    I've been suffering from 0.19 tuning woes for DVB-T for a while
    now. In fact, I originally created ticket #1502 which Daniel references
    in ticket #1552.

    I've just installed the latest svn 0.19-fixes...

    I'd say that tuning speed is much improved over the official 0.19 
release
    but I am not convinced that tuning is anywhere near as reliable as it
    was in 0.18.1. If you are running the official 0.19 release then I would
    recommend upgrading to svn 0.19-fixes. If you are currently running
    0.18.1 then I'd say it's debatable.

> Due to wife-factor I'm not allowed to break our myth box, but I am keen
> to see any improvement in DVB-T tuning speed!
>   
    I simply don't understand why I have completely reliable tuning
    in every other DVB-T application across my Nova-T (tda1004x)
    and AverMedia AverTV DVB-T a800 USB 2.0 tuners while mythtv
    remains problematic (improved but still problematic IMHO).

    Initially, I created a rudimentary patch to mimic tzap's tuning 
mechanism
    exactly. This patch was against the 0.19 official release. The patch 
gave
    me completely reliable tuning.

    After acting as middleman between the linuxtv.org folks and Daniel, it
    appeared he would relent and include the tzap usleep mimickery.
    However, the code has evolved well beyond my ability to follow what
    it now does or how it works. So I cannot check how well it mimics
    the tzap code.

    I'm also finding that mythfrontend loses all input after about 10 
channel
    changes in livetv and livetv playback will occasionally stop with an
    unknown error after a couple of hours. I've upgraded to the latest
    ffmpeg release in an effort to fix the latter but to no avail.

    It seems 0.19 is a problem child with respect to DVB-T in spite
    of all Daniel's great work.

    I'd also suggest that doing a trial upgrade isn't as daunting as you
    may think. I simply stop the myth{front,back}end, stop mysql, tar up a
    backup of /var/lib/mysql/mythconverg and install the new mythtv
    in a separate prefix location from my working one e.g. /usr/local or 
/opt.
    I start up mysql, mythbackend, mythfrontend using the new prefix
    and see how it goes. If I decide it's a lemon I simply stop 
myth{front,back}end,
    stop mysql, restore my tar backup of /var/lib/mysql/mythconverg and
    startup the original versions of mysql, mythbackend and mythfrontend
    using the original, working prefixes. The thing to be aware of is
    that any recordings made during the intervening trial period will be
    lost if you revert (lost to the database but not to the filesystem).

    Anyway, you have my sympathy, DVB-T tuning is not what it once
    was methinks... that's not to say I don't appreciate all Daniel's 
attempts
    to improve it.

    Cheers,

    Doug