[mythtv-users] Questions about Setup Configuration with multiply tuner cards and HD Channel Scanning

R. G. Newbury newbury at mandamus.org
Fri Jan 12 19:57:13 UTC 2007

Jeffrey Born wrote:
>   I am in the midst of setting up the mythtv box.  During setup I have am
> seeing stuff that doesn't seem right.
> I have both a HD3000 card and a PVR500 on a combination front end/back end
> machince.
> I have Charter digital Cable with HD
> Do I setup 3 capture cards or 2?
> How do I know what the video device for the pcHDTV card should be.  It list
> /dev/video0 but I'm pretty certain that is associated with the PVR500 card.
> For the PVR500 card I believe it should be /dev/video0, but probed info 
> says
> it is pcHDTV HD3000.

The PVR500 should show up at /dev/video0 and /dev/video1
You will need the proper lines in your modprobe.conf
The wiki is your friend so I will not repeat what is there.

You could try installing just the PVR500 snd ivtv and see what dmesg 
says. You can soon see whether the install is correct.

If you get the pcHDtv 3000 showing up at /dev/video0 then it is loading 
the cx8800 *analog* module too soon. You want the cx88_dvb module 
loaded. Others have posted here that you can have both loaded, but that 
has never worked for me and I have the same combination. The kernel 
loads these modules very early. I blacklisted the cx8800 module and 
added a script to rc.local to modprobe -r all the cx88...modules, then 
modprobed only the cx88_dvb (it pulls in one other...cx8802 iirc).

Remember that the analog side of the HD3000 card is nowhere near as 
efficient as a PVR and uses the CPU to encode the analog stream to a 
digital stream whereas the PVR500 does that in hardware. I would suggest 
that you only want to do that when you really really really need three 
analog tuners to capture three analog transmissions (and you do not need 
the digital side of the HD3000 to capture a digital transmission).

The HD3000 should then show up at /dev/dvb/adapter0
In mythtv-setup choose the type of card with the reference to 'V3.x' in 
the type selector.

> For the PVR500 card should I use only the standard cable for the zap2it
> information? Basically channels 2-99?

Only channels 2 - 72 or so. ONLY the analog channels.

> For the HD3000 Card choose digital Cable and choose only the HD channels?

Lets be clear: digital is both Standard Definition and High Definition. 
If you say HD when you mean digital, *you* will end up confused because 
*you* will not understand the answers.

Presuming you mean digital, then select your channel lineup including 
only those which are NOT encrypted. Those will likely be QAM256 encoded, 
but the card will deal with that. Do NOT include channels which you can 
only receive through a Set Top Box.. The premium stuff and movie 
channels 200-400 which require a STB.

> What about the digital channels.. anyway to get those to mythtv?  What 
> about
> movie channels 200-400?

The premiumn channels can be fed into mythtv. This involves using an 
irblaster to change the STB box channel, and generally a firewire output 
from the STB into the mythbox. Think of the STB as another (external) 
tuner. This does not use the HD3000 card.

Get the dvb-utils from linuxtv.org and run a scan against your cable 
feed. The HD3000 card will discern a large number of digital streams. 
Some are qam256 encoded SD level digital video. Some are audio only. 
Some are qam256 encoded and encrypted HD level digital streams. Since 
you are in the USA, some few will be qam256 encoded unencrypted HD 
streams (no STB required).

> Scan for channels for the PVR500 works great.  add 2-99 and 116.
> Scan for channels for the HD3000 Card fails for just about every
> combination.. What should I be using?
> I've been trying:
> Scan Type: Full Scan
> Frequency Table: Cable High, Cable HRC High, Cable IRC High, and Cable
> ATSC Modulation: Cable (QAM-256)
> Channel Separator: (5_1) Underscore
> Existing Channel Treatment: Minimal Updates

Those are all correct, except that at the moment the digital scanner 
does not work. There is a TRAC ticket for this.
It also appears that since SVN 11650 or so, the import channels.conf has 
also been broken.

You can get this set up in myth but it takes some hands-on work.
You will have to run a scan with atscscan to produce a raw 
channels.conf, then use azap and the channel name to tune each stream, 
and use mplayer to determine if it is a usable channel. When you have 
chopped the 450 streams down to 30 or so, you can poke the data for 
those channels into the database and 'live happily ever after'.

Post again when you get to that stage if you are still having problems.
The process has been discussed on this list AND written up on the wiki 
with links to outside pages, where the process is explicitly set down. 
On such page is on a site named  penlug.org or penlug,net. It is 
referred to in the wiki. Some of what is written is no longer 
applicable, but the 'finding streams' process is what you need.


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