[linux-dvb] Re: Twinhan DST / TS204 and signal quality questions

[Jukka Tastula <jukka.tastula@kotinet.com>]

On Sunday 15 August 2004 16:19, Werner Johansson wrote:

> Yes, exactly.. Well, I have glitches in the picture and audio from these
> cards, and it's the same issues in several machines (even tried them one
> by one in a W*****s box), same quality metering and same image issues
> from time to time. There are no more than 2-3 glitches per minute
> though, but somehow the STBs aren't affected. Having the tuner inside a
> PC chassis surely doesn't help it, but isn't it supposed to be
> sufficiently shielded by the metal box it sits in, or is this perhaps
> caused by power supply noise?

It should but maybe the manufacturer decided the save a few euros by using 
some cheap parts and in the end you got an unstable card. Could also be 
that the mpeg stream isn't exactly standard and the STBs have some magic 
to correct for these errors better than your card+software. They seem to 
be having some weird standards compliance issues with transmitting here 
anyway. Maybe in other parts of the world, too.

> At least the TER card seems to give somewhat realistic values for signal
> quality and snr as I get really low values (and eventually unlocked
> frontend) when disconnecting the antenna. Similar behavior has been

Yes, I noticed this on my chaintech card also. But the problem is you have 
no way of knowing the scale. How many % is 0000 to 3c31 for signal and 
0000 to 5651 for snr? Mythtv card verification screen says 20% and 32%, 
the windows software provided says 84% signal and 100% quality.