Re: [PATCH] FM1216ME_MK3 some changes

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Hi,

Am Montag, den 27.04.2009, 20:42 +1000 schrieb Dmitri Belimov:
> Hi,
>  
> > Am Montag, den 27.04.2009, 19:29 +1000 schrieb Dmitri Belimov:
> > > Hi All
> > > 
> > > Step by step.
> > > 
> > > This is patch for change only range of FM1216ME_MK3. Slow tunning
> > > is not a big problem.
> > > 
> > > diff -r b40d628f830d linux/drivers/media/common/tuners/tuner-types.c
> > > --- a/linux/drivers/media/common/tuners/tuner-types.c	Fri
> > > Apr 24 01:46:41 2009 -0300 +++
> > > b/linux/drivers/media/common/tuners/tuner-types.c	Tue Apr 28
> > > 03:35:42 2009 +1000 @@ -558,8 +558,8 @@ 
> > >  static struct tuner_range tuner_fm1216me_mk3_pal_ranges[] = {
> > >  	{ 16 * 158.00 /*MHz*/, 0x8e, 0x01, },
> > > -	{ 16 * 442.00 /*MHz*/, 0x8e, 0x02, },
> > > -	{ 16 * 999.99        , 0x8e, 0x04, },
> > > +	{ 16 * 441.00 /*MHz*/, 0x8e, 0x02, },
> > > +	{ 16 * 864.00        , 0x8e, 0x04, },
> > >  };
> > >  
> > >  static struct tuner_params tuner_fm1216me_mk3_params[] = {
> > > 
> > > Signed-off-by: Beholder Intl. Ltd. Dmitry Belimov
> > > <d.belimov@xxxxxxxxx>
> > 
> > if it does help anything for having all above 441 MHz in UHF ranges.
> > 
> > Acked-by: Hermann Pitton <hermann-pitton@xxxxxxxx>
> > 
> > There is simply no known broadcast in that gap on other freq. tables.
> > 
> > Can you please enlighten us who/what broadcasts there?
> 
> I don't know. This trick for solve problem with low sensitivity the tuners on end of band.
> We get it from measuments.

I believe that, since seen before on real broadcast in the VHF low/high
gap.

But if there is no real broadcast at all, what it is all about for now?

You can find this "problem" in theory on almost all "new" tuners, on
every TCL, TENA, YMEC and what the hell else we have melt down to be in
fact only _very few_ new ones.

Get out of the lab, until it is a real problem, but keep in mind.

Cheers,
Hermann

> > > 
> > > With my best regards, Dmitry.
> > > 
> > > > Hi Dmitri,
> > 
> > Cheers,
> > Hermann
> 
> With my best regards, Dmitry.
> 
> > > > Thank you for you responses.
> > > > 
> > > > Just a few more comments...
> > > > 
> > > > On Thu, 2009-04-23 at 20:36 +1000, Dmitri Belimov wrote:
> > > > > Hi Andy
> > > > > 
> > > > > > Dmitri,
> > > > > > 
> > > > > > 
> > > > > > On Wed, 2009-04-22 at 17:48 +1000, Dmitri Belimov wrote:
> > > > > > > Hi All
> > > > > > > 
> > > > > > > 1. Change middle band. In the end of the middle band the
> > > > > > > sensitivity of receiver not good. If we switch to higher
> > > > > > > band, sensitivity more better. Hardware trick.
> > > > > > 
> > > > 
> > > > > Several years a go your customers write some messages about bad
> > > > > quality of TV if frequency of TV is the end of band. It can be
> > > > > low band or middle. Our hardware engeneer make some tests with
> > > > > hardware TV generator and our TV tuners.
> > > > > 
> > > > > If we set default frequency range for low and middle band,
> > > > > quality of TV signal on 159MHz and 442 MHz is bad. When we make
> > > > > our changes with moving end of bands the quality of TV much
> > > > > better. And our system programmer for OS Windows use changed
> > > > > bands for drivers. Customers be happy.
> > > > 
> > > > OK.  A properly run experiment wins over theory every time. :)
> > > > 
> > > > 
> > > > 
> > > > > You can test it if in your placement available TV programm on
> > > > > 159MHz or 442MHz. This trick can be usefull for other tuners.
> > > > 
> > > > If you look at tveeprom.c, a number of other tuners are using that
> > > > tuner definition:
> > > > 
> > > > $ grep FM1216ME_MK3 tveeprom.c
> > > > 	{ TUNER_PHILIPS_FM1216ME_MK3, 	"Philips FQ1216ME
> > > > MK3"}, { TUNER_PHILIPS_FM1216ME_MK3, 	"Philips FM1216 ME
> > > > MK3"}, { TUNER_PHILIPS_FM1216ME_MK3, 	"LG S001D MK3"},
> > > > 	{ TUNER_PHILIPS_FM1216ME_MK3, 	"LG S701D MK3"},
> > > > 	{ TUNER_PHILIPS_FM1216ME_MK3, 	"Philips FQ1216LME
> > > > MK3"}, { TUNER_PHILIPS_FM1216ME_MK3, 	"TCL MFPE05 2"},
> > > > 	{ TUNER_PHILIPS_FM1216ME_MK3, 	"TCL MPE05-2"},
> > > > 	{ TUNER_PHILIPS_FM1216ME_MK3, 	"Philips FM1216ME
> > > > MK5"},
> > > > 
> > > > If your change makes things bad for the other tuners, we'll
> > > > probably have to create an alternate entry for the other tuners
> > > > instead of using the FM1216ME_MK3 defintion.  I suspect most of
> > > > them are clones of the FM1216ME MK3 however, so it probably won't
> > > > matter.
> > > > 
> > > > > > > 3. Set charge pump bit
> > > > > > 
> > > > > > This will improve the time to initially tune to a frequency,
> > > > > > but will likely add some noise as the PLL continues to
> > > > > > maintain lock on the signal.  If there is no way to turn off
> > > > > > the CP after the lock bit is set in the tuner, it's probably
> > > > > > better to leave it off for lower noise and just live with
> > > > > > slower tuning.
> > > > > 
> > > > > We discuss with our windows system programmer about it. He sad
> > > > > that in analog TV mode noise from PLL don't give any problem.
> > > > 
> > > > I would be concerned about phase noise affecting the colors or
> > > > any FM sound carriers.  If the noise isn't noticably affecting
> > > > colors to the human eye (do color bars look OK?), or sound to the
> > > > human ear, then OK.
> > > > 
> > > > 
> > > > >  But in digital TV mode
> > > > > noise from PLL decreased BER.
> > > > 
> > > > I thought the FM1216ME MK3 was an analog only tuner.  I guess I
> > > > don't know DVB-T or cable in Europe well enough.
> > > > 
> > > > 
> > > > > > Leaving the CP bit set should be especially noticable ad FM
> > > > > > noise when set to tune to FM radio stations.  From the
> > > > > > FM1236ME_MK3 datasheet: "It is recommended to set CP=0 in the
> > > > > > FM mode at all times." But the VHF low band control byte is
> > > > > > also used when setting FM radio (AFAICT with a quick look at
> > > > > > the code.)
> > > > > 
> > > > > Yes. You are right. We can swith CP off in FM mode.
> > > > 
> > > > OK.  Thank you.
> > > > 
> > > > > With my best regards, Dmitry.
> > > > 
> > > > 
> > > > Regards,
> > > > Andy
> > > > 
> > > > 
> > > > 
> > 

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