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Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Mon Mar 03, 2014 9:09 pm
by dpdpkpcom
Second this ! :-)

I have put the changes in place as you suggested Constantine, but haven't had the time to watch some of the recorded programs yet, but will report back in due course.

dp

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Sun Apr 06, 2014 9:43 pm
by BeMax
I moved my TBS6985 to another PC with motherboard P5E-V and the TV card works perfect. No counter errors what I could see compared to the other board P7P55D LE. On the other hand I have one TBS 6284 (Quad T/T2) in it works perfect in both machines. My guess is that it's something with the hardware between TBS6985 and some motherboards...

One other difference is that for the P7P55D board I have a PCI-e graphic card. Th P5E board has an inbuilt graphic processor...I don't know if this can be relevant for the problems...

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Mon Apr 07, 2014 12:08 am
by dpdpkpcom
Interesting.

Well, I applied the patch Constantine gave me and since it hasn't been padding the stream to 100mb/s, the problem is greatly reduced, virtually no artefacts at all. Occasionally, if we do get an artefact, it recovers well in less than a second.

Sorry I haven't updated this topic sooner, but I had to watch quite a bit to be sure it was better, which I feel it is.

I think you're right, there is an issue between the motherboard and the tbs card

dp

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Wed Apr 30, 2014 6:53 am
by Krobaruk
Just wanted to add my experiences to this thread. I tried initially with a Tyan S5512 but this could not detect the 6985 at all, then bought an Asus KCMR-D12 which detects the card fine but I had severe artifacting for HD and regular artfacting for SD when using just one tuner. Then applied the patch and when running with only one tuner it now works well (No glitches at all in 4-5 hours total). Wont get to try multiple tuner for another week or two.

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Fri Jun 27, 2014 2:48 am
by dpdpkpcom
Oh dear, the problem persists.

BBC2 HD - wife watching Wimbledon and the artefacts are back with chirpy noises. Currently running Ubuntu 14.04, linux kernel 3.13.0-27 generic. Latest 140425 driver with Constantine's patches applied.

SD programs seem to be no problem.

Just HD programs produce the artefacts.

Is there anything I can provide to help troubleshoot this to get a more permanent fix ? The internet seems awash with people with similar problems, yet others totally not touched by it ?!

Thanks

dp

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Sat Jul 12, 2014 6:17 pm
by Krobaruk
Are TBS planning to investigate this at all? It affects quite a few motherboards. I've tried my 6985 on 2 mnotherboards and it does not work properly on either. The same boards work fine with a mixture of other cards in cluding another TV tuner. Can TBS swap my 6985 for a 6984?

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Tue Jul 15, 2014 4:05 am
by kvaster
I've tested my card in three different motherboards at my home with same LNB.
Result is: it's all OK on windows. And it's NOT OK on linux on every motherboard.
Personally I have Asus Deluxe Z87 motherboard which is really great.

My conclusion is that problem is inside linux driver.

TBS, please fix the problem! For now I just want my money back, card is useless in such setup :/

p.s.: or just send one 6985 card to Luis who developed opensource driver for 6984 in order to have good opensource driver which can be fixed by other people.
p.p.s: I can give access to my gentoo box remotely if tbs developers can investigate that problem remotely.

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Tue Jul 15, 2014 7:13 am
by updatelee
The tuner/demod/pcie interface chipsets are all open source supported, shouldnt be to hard to get it working in open source.

UDL

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Tue Jul 15, 2014 3:07 pm
by kvaster
Card is claimed by manufacturer to be linux compatible, but by the fact linux drivers are not good. Problem was reported long ago, but manufacturer claims motherboards to be the reason and it sounds strange.

Also it's not always easy to write open source drivers for known components - manufacturers adds it's own specific to product. Chip is known, but it may need 'additional initialization' or something else. I'm developer myself, but unfortunatelly I have no linux kernel development experience and for now I really disappointed that I need to investigate problem with drivers for device I've payed money for.

Forum is full of messages about artifacts when watching HD channels using multiple adaptors. And no answers...

Re: Strong Artefacts - Questionable SNR and high BER

PostPosted: Wed Jul 16, 2014 5:11 am
by crazycat
kvaster Wrote:p.s.: or just send one 6985 card to Luis who developed opensource driver for 6984 in order to have good opensource driver which can be fixed by other people.


But now Luis V4L repo have support for 6982 (tested, work ok). TBS frontend drivers some buggy, often crash.

6985 based on same tuner/demod and just need add support to current Luis V4L sources (based on 6984 + 6982).