Channel Scanning on DVB-S(2)

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mirko
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Posts: 2
Joined: Mon Jun 20, 2016 3:31 pm

Channel Scanning on DVB-S(2)

Post by mirko » Mon Jun 20, 2016 3:55 pm

Hi,

I just realized that for some reason the importing channels.conf feature has been removed from MythTV. Instead of using the user-friendly interface of e.g. w_scan (enter position of your satellite and off you go), I now find different options in MythTV, for each of which I have to enter some weird numbers.

Option A, Full Scan (Tuned): Asks for frequency, polarity, symbol rate, etc. but only allows to enter exactly one value in each field, but as just a couple of channels share these parameters I had to repeat this a hell lot of times.

Option B, Import existing scan: Shows an empty list. Looks like a hen-and-egg problem. And according to "the Internet" this is not my "import channels.conf" :(

Option C, Scan of all existing transports: Even allows to "search new transports", but just says "Error tuning to transport" if you haven't configured any.

Option D, Scan of single existing transport: Shows an empty list; also allows to "search new transports", but just says "Programmer Error: Failed to handle tune complete."

So, it looks like that for options C and D I have to add the transports of my satellite manually. But:
1. WTF? Each of them? That was a huge long list of transports that w_scan scanned for me. I have to do all this manually???
2. When I add a new transport I just get an empty configuration window where I can't set anything, and when I click "Finish" nonetheless, I get a new transport with a bunch of zeros. And, surprise, nobody broadcasts on 0 Hz.

So, to conclude: I'm completely stuck trying to get channels into MythTV. So I have two questions:
1. Where is the interface where I just select "19.2E" and get my satellite scanned?
2. If not, what am I supposed to do with those existing interfaces to get my satellite scanned?

I hope, someone can help me and shed some light on these confusing dialogues.

Thanks,

Mirko

jksj
Junior
Posts: 41
Joined: Thu Feb 13, 2014 7:53 pm
Great Britain

Re: Channel Scanning on DVB-S(2)

Post by jksj » Tue Jun 21, 2016 6:47 pm

For the UK follow these instructions http://parker1.co.uk/mythtv_freesat.php.
I always do a Full Scan (tuned) providing parameters for one channel as shown in the link. Apart from the single Frequency parameter everything can be left as auto if your tuner can self detect these parameters.
I have not tried using just Full Scan but presume that would just step through all the possible frequencies.
In the UK channels that belong to a group like Freesat contain information on the other channels in the set so manually scanning for one transport would give the rest if the Search new Transports flag is set.

mirko
Newcomer
Posts: 2
Joined: Mon Jun 20, 2016 3:31 pm

Re: Channel Scanning on DVB-S(2)

Post by mirko » Wed Jun 22, 2016 1:47 pm

Hi jksj,

Thanks for the instructions for UK. However, unfortunately I'm not in UK (by the way, it doesn't really matter where *I* am, it's rather about where my dish is pointing at) and still I have no clue what these numbers do and which numbers I had to enter to get a proper scan. If MythTV would find everything on its own and scan more than I enter there, it wouldn't ask me to enter anything, would it?

So what on Earth do I have to do to get MythTV just scan all the channels on my satellite??? I get the impression, it might be easier to take the channels from w_scan and put them into myth's MySQL database... - Does anyone know how that is structured? Is there just one table with the channels? Is there any documentation on this?

Thanks,

Mirko

noddy
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Joined: Mon Dec 25, 2017 3:03 pm
Bhutan

Re: Channel Scanning on DVB-S(2)

Post by noddy » Mon Dec 25, 2017 3:34 pm

I'm having a similiar experience with a TBS6590 . MythTV can't find anything but w_scan, scan etc find the expected channels and can create a channels.conf that can be used by szap to tune channels.
I've driven myself crazy for two days trying to get mythv-setup to find any channels, or to import a channels.conf. There's a lot of docs out there that imply you can import a channels.conf, but my experience is the same as Mirko's. There is no option I can find in 0.28 ( stock ubuntu 16.04.3 LTS) to input a path to a channels.conf file.
I'm surprised nobody had anything to say about this in a year. Nobody?

MikeB2013
Senior
Posts: 330
Joined: Mon Jul 25, 2016 4:16 pm
Great Britain

Re: Channel Scanning on DVB-S(2)

Post by MikeB2013 » Tue Dec 26, 2017 6:40 am

for a full transponder list of 19.2 see https://www.lyngsat.com/Astra-1KR-1L-1M-1N.html

You only need to use full scan tuned and enter the values for a single transponder, the other transponders should be found automatically using information in the NIT (Network Information Table). I suggest you use :
Freq: 10714000
Polarity: Horizontal
Symbol rate: 22000000

I have assumed that the tbs 6590 drivers have been installed as per the user guide and the DVB-S/S2 delivery system has been set. These multi-standard cards can be a pain to setup in both linux and windows.

The output of "dmesg |grep -i frontend" from a terminal session may help.

Also make sure mythtv backend is not running before using mythtv-setup (sudo systemctl stop mythtv-backend.service on a ubuntu/debian system)

noddy
Newcomer
Posts: 2
Joined: Mon Dec 25, 2017 3:03 pm
Bhutan

Re: Channel Scanning on DVB-S(2)

Post by noddy » Wed Dec 27, 2017 5:59 pm

Thanks for your interest. I certainly tried those parameters for the scan. The driver is working enough for scan (command line util ) to find the channels, and also for szap to tune, although with non default params , as the DVB-S tuners are on frontend1 not frontend0.

The following produced expected results

Code: Select all

w_scan -f s -x > initial_tuning.dat

scan -f 1 -o zap initial_tuning.dat > zap.conf.dat

szap -f1 -c zap.conf.dat "Bloomberg Europe TV" 


Next, I tried tvheadend and found that it couldn't detect any muxes using adaptor 0 and frontend 1 either! However the info tvheadend provided about the adaptor implied it did agree with the TBS6590 data sheet that there was a DVB-S decoder/tuner available on adaptor 0 , not with the above evidence that the command line tools are scanning using this adaptor.

As a desperate shot in the dark I moved the sat cable to the second connector ( adaptor 1 ) and tvheadend immediately found all the expected services, and I was quickly streaming BBC world etc. to a kodi client on my network. My assumption is that if I now try myth-setup for adaptor1/frontend1 it may well find the channels like tvheadend did. Problem remains how to use both my DVB-S tuners at the same time using the TBS linux driver. I guess I'll need to raise it their forum. If/when I try mythtv again I'll note the outcome here for the record.

Thanks again

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