On Tuesday 07 June 2005 14:30, Manu Abraham wrote: > Andrew de Quincey wrote: > > Hi, I've been having (another :) problem with the DVB drivers. Basically, > > at certain sites and with certain channels, cards seem to lose the lock > > after a while.... the average is about 10 hours, so I think its unlikely > > to be that multiswitch incompatability with certain TT DVB-S cards. > > > > This doesn't affect all sites or all channels or all cards - the same > > channels at another site can be rock solid with no issues for months. > > > > The driver is supposed to launch a zigzag scan if it loses lock. However > > this doesn't ever seem to regain the lock with this problem. Simply > > restarting our streaming software (without a reboot) however, _does_ > > regain the lock (only to lose it again after a while). > > > > Snooping with dvbsnoop shows that the signal has been lost, but it does > > appear to be zigzagging to try and require it, but failing (I see the > > lock status varying between SIGNAL and SIGNAL|CARRIER|VITERBI, but never > > above that). > > > > The difference between locking initially and losing a lock after a while > > seems to be the call to dvb_frontend_init(). I'm going to try adding a > > call to this in to the dvb_frontend_thread() loop if it loses the lock > > after a while. > > > > I'm wondering if anyone else sees this? It seems to plague us constantly. > > I had that problem sometime back on the Twinhan cards, that time i > thought it was because the tuners getting too hot.. As a temporary > arrangement i tried a huge blower on the cards. This kept the 3 tuners > cool. > > This never had any effect, whether the tuner was hot/cold. Yeah - I can't test the temperature directly as I'm over 400 miles away from that machine - but I did read the HDD temperature with SMART, and it was 26C. I'm informed the site is air conditioned, and there is loads of open space. I really don't think this is temperature related either. > The periods used to vary, don't know what exactly caused them to vary > either. The variations used to happen something like what you said 10 ~ > 12 hours or sometime it was 48 hours. But 72 hours seemed the maximum > that it would go many times. Interesting - thats exactly it.. so its across completely different card architectures!? (I assume you're still talking about the twinhan cards here) > Somebody at one of the universities in prague who was streaming in the > unversity campus also had the same problems.... I seem to remember hearing from them as well, but we didn't manage to find a resolution. > > I suppose these cards are really meant as consumer grade ones for zapping > > channels, and not really designed for 24x7 reception on a single channel. > > I don't think it was the hardware, as the drivers from the manufacturer > worked fine, eventhough they had their own share of the problems and > bugs.. :-( I wonder whether those drivers lose the lock and retune quickly, or if they don't lose the lock at all? I'm hoping we can at least retune so its not such a big hassle - obviously some data is going to be lost, but its better than nothing (certainly better than it going down completely + irate clients etc).
