[mythtv] "SOP: SERVICE 173" on qam cable...what is it? can myth use it?

Steve Adeff adeffs at gmail.com
Tue Jan 10 14:17:26 UTC 2006

On Tuesday 10 January 2006 00:27, Michael Freeman wrote:
> hmm.  when i played the raw capture in my windows box, i could hear audio,
> pauses, more audio, done. so maybe the guide hides on the back of a QAM256
> audio channel.
> if someone wants to look at it (since maybe there's something that would
> work across the comcast world in it), i can post it.
> i'd try, but, well, i'm sure i'd still be trying to figure it out when
> someone here made it work with myth.
> from what little i can figure out, the first problem is the lack of the
> 0x1ffb PID that the ATSC spec says is some sort of a master PID.
> On 1/9/06, Daniel Kristjansson <danielk at cuymedia.net> wrote:
> > On Mon, 2006-01-09 at 23:43 -0500, Michael Freeman wrote:
> > > I was scanning around my comcast feed with my pchdtv 3000 when i
> > > locked onto something interesting...channel 93 had a ton of PIDs
> > > between 0x1000 and 0x1ffb (but no 0x1ffb entry).  Cracking this file
> > > open in a hex editor reveals a lot of things called "SOP: SERVICE"
> > > followed by what look suspiciously like digital channel numbers (for
> > > instance, 173 is ESPN HD here...and I saw a "SOP: SERVICE 173" packet
> > > in the file.
> > >
> > > Anyone know what this means and if myth can be hacked to make use of
> > > it?
> >
> > I haven't seen anything like this with RCN, but this is probably your
> > listings/guide channel. The Cable box tunes to that to populate it's
> > EPG, so it doesn't have to channel hop like we need to do to get ATSC
> > EPG data. It could be reverse engineered to provide the same data for
> > MythTV. Though there is probably already a standards document for it,
> > as this isn't top secret information or anything.
> >
> > -- Daniel

what was the audio you were hearing? I was able to find many of the music 
stations on my digital cable line out in the open. The thing was, they had no 
video pid associated with them, so they had to map seperately.
Or did it sound like you were watching ESPN? maybe record a good 5-10mins of 
that "station" to see if you can identify what it was?


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