[mythtv-users] basic ota hdtv questions

[steve at clayfish.net]

----- Original Message -----
From: joe byrne [mailto:mythjoe at gmail.com]
Sent: 12/22/2005 3:02:35 AM
To: mythtv-users at mythtv.org
Subject: [mythtv-users] basic ota hdtv questions


> I just installed an air2pc card (the version with the bcm3510) to
> record atsc OTA.  It coexists with an ivtv card and a bttv card, which
> both record OTA.  Yes, I like variety.  I'm running mythtv 18.1
> installed from rpms on FC4 with  a 2.6.14 kernel. I'm in the US and
> use zap2it.

I have the same card and recently set it up on a slave backend with FC4 and atrpms according to Jarod's guide.

> 
> I have some really basic questions:
> * Do I need a second zap2it line-up for the ota-hdtv input?
> * Some of the digital channels duplicate analog channels.  Is there a
> way to equate the two?  E.g., I have an analog channel 7 and a digital
> channel with the same programming.
> * Is there a way to equate zap2it digital channels with the underscore
> (e.g. 7_1) with the channels added by scanning w/o the underscore
> (e.g. 71)?
> * Some of the digital channel numbers duplicate analog channel
> numbers, but carry different programming.  E.g., I have a digital
> channel 11 (identified by scanning) and an analog channel 11 that seem
> to be completely unrelated.  Will this cause a problem?

It took me awhile to wrap my head around this problem, but this suggestion from the linuxtv list worked for me:

http://www.linuxtv.org/pipermail/linux-dvb/2005-February/000342.html

The scanned hdtv channels from mythtvsetup have the tuning information and the zap2it hdtv channels have the program guide info.  I would kill the backend before doing this.  After matching the scanned channels to the corresponding zap2it channels, I copied serviceid, mplexid, and atscsrcid from the scanned channel to the zap2it channel in the channel table in the database.  Instead of 
hiding the scanned channels as the post suggests, I just deleted them, leaving the zap2it channels (5_1, 5_2, 17_1, etc.)  Be sure to set a starting channel for the card to one that exists in mythtvsetup.  I also changed the type for each zap2it channel to atsc in mythtvsetup - channel settings, since I was using a cable type as the default for the global backend setting.

That should leave you with your old analog channels and hdtv channels.  I find it is good to have both for the same stations, in case my air2pc card is tied up recording another show I can still record another channel in analog.  Myth just treats them as separate channels and knows which card to use.
  
I also ran into problems on reboot with this card.  For lack of a better term, it had to "warm-up" a few minutes before starting the backend service, otherwise it would fail to tune in to the start-up channel, blank out the start-up channel and fail to start again until I ran mythtvsetup and put a start-up channel again.  Apparently this is a problem with these first generation air2pc cards.