On 16/02/07 19:54:45, Richard Scobie wrote: > > > lynx.abraxas@xxxxxxxxxx wrote: > > >This is very valuable to know. Sadly I couldn't find any info on this in > >the > >net. > >What would You recon is ment with "signal strength" and "signal quality" > >in > >the M$ windows dvb-t programme? Would it be SIG and SNR as > >reportet by > >dvbsnoop or tzap? What do the other values discribe? SNR is never > >changing although it is reported. Here is some output of usbsnoop and > >tzap: > > > >tzap ard > >using '/dev/dvb/adapter0/frontend0' and '/dev/dvb/adapter0/demux0' > >reading channels from file '/home/lynx/.tzap/channels.conf' > >tuning to 191500000 Hz > >video pid 0x0201, audio pid 0x0202 > >status 03 | signal 8675 | snr 0000 | ber 001fffff | unc 00000000 | > >status 1f | signal 8435 | snr 0000 | ber 00000000 | unc 00000013 | > >FE_HAS_LOCK > >status 1f | signal 8455 | snr 0000 | ber 00000000 | unc 00000000 | > >FE_HAS_LOCK > >status 1f | signal 844e | snr 0000 | ber 00000000 | unc 00000000 | > >FE_HAS_LOCK > > The crucial ones here are ber and unc. > > Ideally both should be zero. BER is a measure of bit errors in the > stream and up to a certain point, these errors are fully corrected with > the original data able to be recovered by using the error correction > code which is part of the encoding. > > Once the number of errors exceeds the error correction capability, the > picture/sound starts to show visible/audible artifacting and this will > show up in the unc - uncorrected errors column. > > I am a little puzzled as to why the second entry in your example is > showing uncorrected errors and yet has a ber of 0. > > The ber numbers can be quite useful for fine tuning your dish alignment, > particularly LNB skew. Thanks for all Your answers. What is the difference between SNR and CNR? I also wonder why my telitext pages are often not complete although BER and UNC are zero. Is telitext in its own stream as subtitles would be? Thanks again Lynx _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
