On 08/13/2007 09:55 PM, Manu Abraham wrote: >>> Can you describe the problem that you face ? other than low SNR ? ie >>> have you checked whether your cables are okay, Dish is aligned proper >>> etc etc ? It will help to avoid a lot of frustration later. :) >>> >>> >>> Manu >>> >> That's great! >> >> The problems I face: I have a lot of BER, measured with femon -h (with >> my patch applied for decimal readings). The sky is clear. Visiosat Bisat >> G3C dish. >> >> On ZDF on Astra 19,2 east (Astra 1), I see nothing (and I mean >> _nothing_) but green and purple blocks and loud aliens in my speakers >> constantly. BER is into 65000. >> >> On Omroep Brabant on Astra 1D at 23,5 east, I see some bits from the >> image but constantly lots of complete stripes with corrupted MPEG, and >> the audio is also bad. So this stream is also corrupt. BER into 65000. >> >> Now ZDF is one of the weakest transponders on 19,2 east and Astra 1D is >> old so doesn't perform optimal either. But this is not normal. >> >> On BBC One/Two/Three/Four on Astra 2D, and that beam is strong in my >> location, the picture is good most of the time, but once approx every >> minute a small visible corruption passes by. Just as long as it does >> _not_ start to rain, I can follow the program. BER into 65000. > > > I understood your problem. > >> On the Dutch channels on Astra 1 at 19,2 east again, like Nederland 1 at >> 12515.25 H (Astra 1G) or RTL 5 at 12343.50 H (Astra 1H) the picture is >> perfect, and BER hoovers and shows 0, 256 or 512 (which is low). >> >> There are also values in between. n-tv on Astra 1 at 19,2 east shows >> around 17000-18000. Perfect picture. >> >> But.. When it starts to rain, the whole party is over. > > > During rain, don't expect anything much with DVB-S With just a little normal rain, DVB-S should work fine. Only when there's hard rain and it's seriously cloudy you could expect the picture to actually fail with a properly set up dish. Overall DVB-S is very reliable. DVB-S is also used as a feed for many cable channels in The Netherlands, and they hardly ever fail. > > >> So that's my problem. When I swap the KNC1 for my Technotrend S-1500, >> all the channels work, including ZDF, perfectly, and the BER is zero >> everywhere, even ZDF works with zero BER. There are many other channels >> that do not work but I couldn't possibly list them all, I don't think >> that would make sense anyway. And sure, there could be a little >> difference in tuner quality and stuff in favor of the Technotrend, but I >> really don't believe it would be that big for cards from the same price >> range. And it's not like Philips is a bad or cheap brand either. > > > Though i am not saying it is bad, devices designed improperly leads to > bad results. However good the components are. We have examples, but > not stating that is the case here, but a possibility. Yes, that's true. > > >> I'm actually not sure the SNR number in femon is low, I was really >> talking about Signal to Noise ratio - with all that corruption and >> horrible performance it has to be bad. >> >> On Windows, I can watch ZDF with the KNC1, but I see some "error" level >> in the Windows software, that "error" most likely means BER. But it's >> not much. Last time I checked anyway, it's been a while since I've seen >> Windows. > > > If this is an overall problem that you see, then it has nothing to do > with the drivers. I thought in your case, the driver was misbehaving It's not an overall problem, I only have this problem with the KNC1 card. > > The TT card you have behaves similarly ? The TT card performs fine, I still have to test it in somewhat harder rain, but the fact it shows ZDF perfectly without even BER is a huge difference. I also have a Vantage standalone receiver. I did test that one in rain, and ZDF would just keep going. > >> The problem seems to be getting worse, because some days/weeks ago I >> believe I had zero BER at the Dutch channels, and now it's around >> 256-512. But the weather, temperature and other stuff also varies, so >> it's always hard to say. > > > Maybe it has something to do with your dish alignment, LNB alignment > etc ? A LNB skew can cause a lot of errors to happen, eventhough the > dish is aligned correctly. > Trust me, I know stuff about alignment. I have re-aligned the dish 5 or 6 or more times and _every_ time the result did not fully satisfy me. I changed the height of the dish, how deep the LNB was into the holder, the skew, tried moving the LNB holder up and down (possible on my dish), I tried everything. Even swapped the LNB's, but that made no difference either. The last couple of times, I took my laptop up on the roof so I could VNC to my desktop and see the signal/BER instead of using the cheap satbeeper. Then I swapped the card for the Technotrend, and checked the status... Heeeeey... No signal trouble? But OK.. The Common Interface on the S-1500 is totally not detected, dmesg never heard of it, it's really like it isn't there, and it's required for the Dutch channels. So my choice at this moment is a good signal but no Dutch channels, or a crappy signal and Dutch channels. So what do you do then.. _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
