[linux-dvb] Re: Signal monitoring with dvbtune -m

["Terry Lewis" <terry@kryogenic.co.uk>]

um, ignore me, its 3:45AM, kinda wired atm :)

I meant freq = ((channel no)*8+306)+/-0.167

so you got it right.

(/me refrains from answering mailing lists in his present state)

are you using an internal aerial btw?


> Oops, replied to author and not list, sorry :)
>
> looks like you have added 167khz as opposed to 166666 hz
>
> its freq = ((channel no)*8+306)+/-166666
>
>> I've got a Hauppauge Nova-T card and I'm having reception problems with
>> the channels on a particular frequency (530167000Hz from Rowridge: ITV,
>> C4 etc). I get these sort of figures from
>> dvbtune -f 530167000 -m
>>
>> Signal=52428, Verror=6160, SNR=65278dB, BlockErrors=0, (S|L|C|V|SY|)
>>
>> The Verror fluctuates, 6160 is somewhere in the middle.  Despite it not
>> reporting any block errors the picture has obvious MPEG artefacts
>> constantly and it's quite unwatchable. The picture immediately starts
>> lagging badly behind the sound, then the sound disappears after about a
>> minute - except with vdr-xine, xine has usually crashed by then.
>>
>> Other channels - at least the ones I care enough about to have checked
>> so far - seem OK. For 489833330Hz (BBC etc) Verror is around 50, for
>> 556433330Hz (Channel 5 etc) it's around 1200. The other figures are the
>> same for all 3 frequencies and don't fluctuate.
>>
>> I saw a mesasge in the archives which said that you should be able to
>> maintain a stable picture with Verror below 10000 and that these
>> figures:
>>
>> Signal=13107, Verror=14191, SNR=47802dB, BlockErrors=0, (S|L|C|V|SY|)
>>
>> should be "good" with some artefacts every few minutes with changing
>> atmospheric conditions. Assuming low Verror and high Signal and SNR are
>> good, my worst figures are better than that, but it's unwatchable.
>>
>> If I ran dvbtune -m and kept an eye on the figures while I moved the
>> aerial would that be a good way to improve reception in case it isn't
>> aligned properly?
>>
>> --
>> TH * http://www.realh.co.uk
>>
>>
>>
>
>
> Regards,
> Terry Lewis
>
>
>


Regards,
Terry Lewis