[mythtv-users] PVR-150 Tuner Quality Issues

[Michael T. Dean]

On 04/16/2006 04:41 AM, Michael Horn wrote:
> First of all it looks like I mis-spoke in my last reply. It wasn't 
> that my tuner wasnt detected properly, it was that its type was being 
> set incorrectly. I've been playing around with the setup, and if all 
> tuner=xx options are removed,  it is detected as type 4. However, type 
> 4 seems to be equivilent to tuner not found or something of the sort 
> (at least according to 
> /usr/src/Documentation/video4linux/CARDLIST.tuners) So if I leave it 
> without a tuner=xx option, or try to set it to 4, its unsuccessful, 
> and I can only tune the channel that was last tuned, with no ability 
> to change it. When set as type=50, which I chose originally as it was 
> the closest match to my TCL M2523_5N_E. With that option, I can tune 
> all my channels, but with the quality issues.

Tuner type 4 is "No Tuner."  It's used by cards without tuners.  Also, 
when a card has a tuner whose tuning characteristics have not yet been 
"identified," it's type is set to 4.  Therefore, the tveeprom module 
(which contains mappings of card data to tuner module characteristics) 
did not have any information to allow /auto-detection/ of your tuner type.

Your tuner's (TCL M2623_5N_E) characteristics were not yet identified as 
of ivtv 0.4.4 and 0.5.x and 0.6.x rely on the in-kernel tveeprom for all 
autodetection.  The tveeprom in the V4L CVS (which is slightly newer 
than the most-recent in-kernel module) has not yet identified the tuner 
characteristics for your tuner, either.

Therefore, you must pass a "tuner=" module option to ivtv ("options ivtv 
tuner=xx") to select the closest match (at this point, there are only 75 
to choose from--and you've already tried #4 ;)--but you can narrow that 
down by selecting only the NTSC or PAL tuners as appropriate).  Your 
best bet for finding the right tuner is the IvyTV mailing lists.  There, 
you would likely find the closest matches (and, whether that's a true 
match or whether you need to patch your tuner module for proper reception).

As Brian mentioned, using an external tuner (i.e. using the S-Video or 
Composite inputs) is another option.

Mike