Web lists-archives.com

Re: [PATCH] FM1216ME_MK3 some changes




Hi,

Am Sonntag, den 26.04.2009, 23:58 +1000 schrieb Dmitri Belimov:
> Hi Andy 
> 
> > Hi Dmitri,
> > 
> > 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.
> 
> We can make fake FM1216ME_MK3 compatible tuner for clones. And move clones to it.
> After testing each clone with real compatibility with FM1216ME_MK3 we can move to real tuner.
> 
> > > > > 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.

Some confusion probably started here.

You were talking about one more different tuner ...

> > 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.
> 
> Ok. I'll discuss about it with our system programmer.
>  
> > >  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.
> 
> Yes, you are right. This solutions used for hybrid tuners too.
> 
> > > > 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.
> > 
> > > 
> > 
> > 
> > Regards,
> > Andy
> 
> With my best regards, Dmitry.
> --
Cheers,
Hermann


--
video4linux-list mailing list
Unsubscribe mailto:video4linux-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/video4linux-list