[linux-dvb] Re: Unable to get ITV mux

[Gavin Hamill <gdh@acentral.co.uk>]

On Sunday 18 January 2004 22:06, James Mulcahy wrote:

> james@neon:~/projects/DVB/apps/scan$ dvbtune -f 810167
> Event:  Frequency: 820767000
> Bit error rate: 5454
> Signal strength: 50629
> SNR: 63993

Now that's better a BER of 5000 is a 'OK' -  'good' signal should be under 
1000..

And it seems to apply that 10060 frequency-shift on every input freq - very 
strange!

> james@neon:~/projects/DVB/apps/scan$ dvbtune -f 823567

> FE_STATUS: FE_TIMEDOUT FE_HAS_VITERBI FE_HAS_SYNC
> Not able to lock to the signal on the given frequency

OK fair enough - that was a long-shot :)

> It seems to be back consistently now (I think it disappeared for my last
> mail because I'd moved some aerial leads around; I've now removed anything
> except the Nova-T card from the aerial and I'm back to where I was before
> - sorry about the confusion).

Because ITV pack their data much tighter (QAM64 instead of QAM16), it requires 
the signal strength be considerably higher, so you may simply be experiencing 
a poor quality signal.

If nothing else, you can try looping the RF through a VCR or a Sky box, since 
it'll tend to boost the signal slightly - might just be enough to get you 
going.

> So it looks likely that it's the Bit Error Rate which is causing me
> problems :( - Any thoughts on why it might be so high on one frequency,
> but fine on others ?

See above :)

If the logic is correct, then you should also be having trouble receiving the 
'SDN' mux containing 'five' , QVC, and the BBC Radio 1-4 streams..

Cheers,
Gavin.



-- 
Info:
To unsubscribe send a mail to ecartis@linuxtv.org with "unsubscribe linux-dvb" as subject.