Kbtv2 beta2 uploaded

[Danny Pansters]

On Sunday 24 February 2008 18:03:47 Dieter wrote:
> In message <200802250056.18550.danny at ricin.com>, "Danny Pansters" writes:
> > On Friday 22 February 2008 18:59:44 Dieter wrote:
> > > > > > Your card seems to have a microtune tuner mt2050 which is not yet
> > > > > > supported by the saa backend. I'm looking into it. Unfortunately
> > > > > > it differs from the other generic tuner APIs for saa in that
> > > > > > tuning and init are to be handled differently (mt2032 is
> > > > > > supported by bktr, so I can peek there). THis is an important
> > > > > > tuner to have support for though for several reasons:
> > > > > >
> > > > > > - it's on a chip, not in a large chunky metal enclosure
> > > > >
> > > > > I have read that the very small USB tuners don't perform as well as
> > > > > the "large chunky metal enclosure", because some features were left
> > > > > out.
> > > >
> > > > Well, they don't have an mpeg encoder chip, but neither do the old
> > > > fashioned analog TV cards. Of course, supporting that A/V decoder is
> > > > another matter. But so is supporting an onboard mpeg encoder.
> > > >
> > > > They seem to use empia chipsets almost exclusively, the variant
> > > > without onboard MPEG encoder is called the "blackbird" design IIRC.
> > >
> > > No, I mean the reception performance, not mpeg features.  The "big"
> > > metal cans supposedly have better RF filtering.  Keeping the undesired
> > > frequencies out is important.
> >
> > I've been looking into how they work and what they do is they have two IF
> > stages. They demodulate to higher frequencies first (order 1200 MHZ) then
> > do the usual demod to actual IF (for PAL, ntsc, but also QAM etc).
>
> I think you mean "frequency shift" aka "mix" rather than "demodulate"?

Yes :) Jargon overload...

>
> http://en.wikipedia.org/wiki/Modulation
> http://en.wikipedia.org/wiki/Frequency_mixer
> http://en.wikipedia.org/wiki/Heterodyne
> http://en.wikipedia.org/wiki/Superhet
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