[mythtv] DVB patch

Taylor Jacob rtjacob at earthlink.net
Fri Nov 19 01:41:09 UTC 2004

> This seems like a time to bring up another problem I've noticed with the
> transponder list. If you scan a network with multiple transponders that
> are on the same frequency (like the spot beam transponders on Echostar
> 110W/119W) you will end up with with multiple copies of the same channel
> in in the database, with one copy pointing to each of the transponders
> at that frequency. Also if none of the transponders are accessible in
> your area you will end up scanning the same dead frequency four or five
> times.

The NetworkID/TransportID is actually used for maping the services.. Who cares
if you get 6 copies of the transponders?  They timeout pretty quickly, and you
never have to scan again.. (At least when all of this is done..  In the end
once the satellite is scanned once it will always keep it the database up to
date)..  I am not aware of spot beams being used anywhere other than
DishNetwork and DirecTV which you cannot use with MythTV and a DVB card since
Dish does not support CAMs and DirecTV is not DVB standard..  What are you
accessing on 110/119W?

> I'm not sure what the best way is to handle this. If it is not vital
> that the channels map to the proper transponder *number* then it's
> simply a manner of adjusting the scanner to add "GROUP BY frequency" to
> the SQL statement that retrieves the list of transponders to cancel. The
> other option is to add another column to dvb_transponders that allows a
> transponder to be marked as "do not scan." Whether or not this can be
> filled in automatically based on data in the stream I do not know. I
> will try to look into it this weekend.

I had always thought that the NIT tables would not be verified all the time once
they were initially populated.. Its not very often that a new multiplex pops
up.. I.E. Its an edge condition that probbably causes more problems to be
verified than to just force the user to do a re-scan..  I could be wrong on
this, but I don't see this being a big deal..


More information about the mythtv-dev mailing list