missing muxes

Added by Cotie Jones over 10 years ago

I think that the default dvb network ("Add DVB Network by location") for the U.S. "Cable-Standard-Center-frequencies-QAM356" is missing essential muxes. I live in Washington, DC area and each time I have installed TVHeadend, key freq/mux/channels have been missing - I assume this is b/c of unfamiliarity with US qam/atsc freq. maps by the (brilliant) European developer(s). As I am using the dvbhdhomerun driver, I am not able to manually add muxes in the web interface (see I tried to add two of these muxes manually by creating appropriate files and dropping them into /home/hts/.hts/tvheadend/dvbmuxes/, but that also did not work. The muxes that I wish to add are near the frequency extreme (843K and 849K Mhz), but contain my local FOX affiliate station, public TV station and other important channels. I would gladly provide the developers with a freq. map for Comcast Cable, the major provider on the Eastern Seaboard of the U.S. if this would assist in adding these muxes. How would I go about this so that they can update the code/ add these muxes?

Replies (8)

RE: missing muxes - Added by Cotie Jones over 10 years ago

No one has responded to my prior post. So...., can additional muxes be added to binary for N.A. QAM? ("At the moment the muxes are compiled into the binary itself" - Andreas Öman). Wikipedia lists the appropriate "muxes" for my country's cable as "QAM Carriers" which go from 57Mhz to 999Mhz (, but specifically, I need muxes for 831, 843, 849 and 855 Mhz, which are now missing from TVHeadend, which only goes up to 801Mhz. Please respond?

RE: missing muxes - Added by Hein Rigolo over 10 years ago

Tvheadend takes it information about muxes directly from the central repository of the dvb-apps utils. Each time a new official build is created, the latest set of initial scanning files is taken from there and converted into information that tvheadend then incorporates into it's binary. The program that actually is doing that transformation can be found in the src/muxbuilder directory in the tvheadend source code.

You can find the latest set of initial scanning files here:

for the US you need to look into the atsc directory I assume.

If the frequencies that you need are not listed there you can send an email to the linux-media mailinglist with an updated version of the file. Then the maintainers of these files can update the required files. You can also update the file your self, run muxbuilder and then compile tvheadend from source.

There is also issue number #72 which asks to be able to specify/import these files directly instead of making them hardcoded into tvheadend.

RE: missing muxes - Added by Dustin Johnson over 10 years ago

I was in the same boat, living in Arlington, VA, so I locally modified the tvheadend source code to include muxes up to 855 MHz (the highest frequency my tuner card can tune to) in ATSC_us_Cable_Standard_center_frequencies_QAM256. You can try out the source code here --> I just ran a scan and, while it now scans the higher frequencies, the highest mux in which the card detects activity is still 765 MHz. Let me know if you have any luck.

RE: missing muxes - Added by Cotie Jones over 10 years ago

Yeah, I tried to contact linux-media mailinglist per Hein's instructions, but I wasn't really sure how to do it, so I just posted a file which included all of the muxes allocated for NA Cable to the list email, but I got no response and the file never changed. I could not figure out how to modify the source code, so thanks. It would be good if the dvb-apps file could be fixed, as I am sure that many people might abandon what are very good Linux apps such as Tvheadend because they are inexplicably (to near noobs like me), missing really necessary functionality, because it relies on bad/antiquated source data.

RE: missing muxes - Added by Cotie Jones over 10 years ago

PS - How did you go about modifying the source code?

RE: missing muxes - Added by Dustin Johnson over 10 years ago

No problem. The linuxtv_muxes.h header file in the src directory contains a struct for each set of DVB muxes. I just added the additional frequencies to the end of the muxes_ATSC_us_Cable_Standard_center_frequencies_QAM256 struct (lines 14142-14150) to get the additional scanning. Of course, you would have to do this again each time you upgrade to a new version of tvheadend.

RE: missing muxes - Added by Cotie Jones over 10 years ago

Right. Hey, by the way, your modified source worked perfectly for me. I now pick up WTTGHD, WDCW digitals and the WMPT digitalls, which I couldn't before. I am in Pr. Geo's County, MD. Thanks again for the assist.

RE: missing muxes - Added by Cotie Jones over 10 years ago


I just can't catch a break with tvheadend. Now I am locked out of the install, can't login to web client(so can't use with XBMC). Startup with -C does not work, either, still won't let me into web interface.I have absolutely no idea how to fix this.