Autor Thema: DVB-c linux woes! TV-headend fail windows success!  (Gelesen 7465 mal)

kanifee

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DVB-c linux woes! TV-headend fail windows success!
« am: Dezember 04, 2016, 12:23:21 Nachmittag »
Ok, long time lurker, first time poster. Bit of a sod of a first post to so i do appologise!

I'm hoping somebody out there can help me, im pretty close to tearing my own hair out. I recently purchased a sandtek DVB-C/T usb stick that supports windows, linux and a host of other OS and embedded devices.
My ultimate goal is to have a small TVheadend server and kodi clients in rooms receiving the broadcasts. All very simple... in theory.

My initial steps upon recieving the stick was to install it on my raspberry pi2 running open elec, i enabled the TVH server and set about configuring it, upon initiating a scan i received a failed tune, this theme continued for a couple of hours, i then ran a successful scan returning 255 channels, 20 + of which are usable as they are not scrambled, great you say? that's what i thought. I set about mapping the scans but on completion all scrambled channels did not map ( hardly surprising, and not realy an issue) and some FTA didn't map either, this is a issue.

After another hour fiddling i decided to delete the results and re-scan. i entered the figures as i thought i entered them first time around but got no results. i spent another hour or two on this with no luck what so ever. Starting to get miffed i went to my DM800se, installed all the relevant software and ran a scan with the stick, 60 channels found, most of which are scrambled and only about half of the FTA i should see listed.

Frustrated i installed the stick on my windows machine, the best option for scanning i could find was mediapportal 2, using the brute force option it found all the channels and mapped every single one success! Ok so now i have all the frequencies and sym rates for the channels MP2 has found, should be a piece of cake on any other system right? Well no, it isn't, using the frequencies and sym rate, even the NET ID from the MP" scans TVHeadend still returns no results, this is on a RPI2 with 2 different installs and builds of libreelec and a freshly installed copy of ubuntu 14.x on my laptop.
I ran a W_scan from the fresh linux install verifying that it see's the stick correctly, has the correct sym rate input and scans a range of 43khz to 100.1khz, it returns a blank scan saying it can find nothing on the network, I let the program use the predefined settings and it returns the same again, nothing detected.

Just to make sure i reinserted the stick into my windows machine and redid the MP" scan, it scanned every single channel! Oh and MP2 reports excellent signal on all it's scans, all FTA channels are viewable also.

I have also installed a piece pf spftware on windows called DVB dream, this is also able to scan all channel both by brute force and by me manually inputting the freaquency's so for now im leaning towards some issue between linux and the driver software. Only issue is im pretty ignorent on linux!

Im at my wits end, can anyone shed any light on this or give me a direction to move in to, MP" just isnt the software to be running a Tv server, it's clunky, runs on windows and is a PITA.


Im in the UK, newcastle upon tyne trying to access the virgin network

Sundtek

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Re:DVB-c linux woes! TV-headend fail windows success!
« Antwort #1 am: Dezember 04, 2016, 12:47:41 Nachmittag »
Hi,

failed tune is okay - but it also very much depends which initial frequency list you are using.

failed tune means that the given Frequency does not carry any DVB-C transponder, some initial scanfiles carry frequencies for multiple areas.

The bruteforce scan in Windows really tried to scan every single frequency (and it was more successful than the scanfile which you have set up with tvheadend).

Did you try to check the DVB-C cable?

Please note that if you use the tuner with a Dreambox do not loop the signal through the settopbox as this might have some negative impact on the signal quality. Use a splitter infront of the settopbox.
« Letzte Änderung: Dezember 04, 2016, 01:05:16 Nachmittag von Sundtek »
Failure is a good thing! I'll fix it

kanifee

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Re:DVB-c linux woes! TV-headend fail windows success!
« Antwort #2 am: Dezember 04, 2016, 01:32:40 Nachmittag »
Ok. you will have to bare with me here, pretty new to all this.
So from what you are saying i need to scan the correct single frequency that carries the information for all the other frequencies? Ok, so that means that i have the correct frequencies, i just do not know which it is. Although after searching for quite a while i did find a default set of scan frequencies that others have seemd to use with success and returns a group of channels when this single frequencies is scanned but returns zero under linux/tvheadend
What i do not understand is, i have carried out a few full scans through the whole range with W_scan in linux and it returns so signal for any scanned frequencies.

Sundtek

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Re:DVB-c linux woes! TV-headend fail windows success!
« Antwort #3 am: Dezember 04, 2016, 01:41:49 Nachmittag »
If there is a difference between the windows and Linux (w_scan) scan result you will have to check your DVB-C cable.

You can scan single transponders with following commands on the Raspberry PI:
Zitat
/opt/bin/mediaclient -m DVBC -f 113000000 -M Q64 -S 6900000

/opt/bin/mediaclient --readsignal=0 -d /dev/dvb/adapter0/frontend0

please note you will have to change the the parameters: frequency (113000000 Hz), Q64 = QAM64 (Q256 would be QAM256), -S 6900000 = Symbolrate 6900 KSYM)

The readsignal command can be aborted by pressing ctrl-c

In case of a bad signal, some customers also reported that using a USB extension will improve the signal with a Raspberry PI (up to 1 meter) and put the tuner as far away from the RPI as possible.
Failure is a good thing! I'll fix it