[mythtv-users] USB tuner advice for UK DVB-T

[John Pilkington]

On 23/09/12 21:03, Roger Siddons wrote:
> On Sun, 23 Sep 2012 09:02:22 +0100, Nick Morrott
> <knowledgejunkie at gmail.com> wrote:
>
>> On 22 September 2012 23:49, Roger Siddons <dizygotheca at ntlworld.com>
>> wrote:
>>
>>> I've been very impressed with the dual tuner
>>> http://www.linuxtv.org/wiki/index.php/Kworld_UB499-2T (T09 version)
>>> that you
>>> can pick up from Maplin's for £17 (Code A17HG). It needs a 3.2 kernel
>>> (ie.
>>> Ub 12.04), you have to install the firmware, it mucks up the backend
>>> log and
>>> the remote is rubbish.
>>> However it's been reliable and has provided perfect recordings for
>>> the past
>>> 6 weeks. Much better than my Hauppauge PCI; it's now become my primary
>>> tuner. Build quality is questionable but for that price I don't need
>>> it to
>>> last forever.
>>
>> Reading the LinuxTV wiki page (and noting the section about disabling
>> the PID filter) it is still not 100% clear to me whether each tuner
>> will pass through the whole transport stream and therefore support
>> mutlirec in MythTV. Are you able to confirm or deny whether this dual
>> tuner is multirec-capable?
>>
>> Cheers,
>> Nick
>> _______________________________________________
>
> Yes multi-rec is fine, in that one tuner will record 3 channels from the
> same mux simultaneously. I did try that PID filter option but it
> prevented the tuners from working at all so I removed it and can live
> with the 1 Hz log messages. I haven't investigated further - I don't
> fully understand PID filters - so might have another go when I find
> time. Maybe it needs a cold start or something.
> FWIW I couldn't get a usable firmware following the wiki method either.
> But google found one that worked easily enough. Again I don't understand
> the difference between Windows/Linux firmwares so haven't commented on
> the wiki yet.

I wrote the original note on the wiki about the transport-stream filter, 
and I was never able to disable it.  I still have the device but haven't 
used it for some time.  I think the limitation was thought to be most 
significant for muxes with a large number of streams - such as the BBC 
SD one which has many radio channels.  Of course the device I have might 
not be the one currently being shipped under the same label ;-)

Maybe I'll give it another go.  My current usb twin-tuner device is the 
704J, which also came from Maplin.  That claims, in dmesg, that it 
passes the full data stream.  Project-x finds a few packets out of order 
or the wrong length, but usually sorts them out ok. Visually the 
recordings show only occasional glitches, both before and after PX.  DVD 
authoring after PX has no problems.  I have it as my third and fourth 
device, after two utterly reliable single tuner PCI cards at 5 VTs each, 
and it doesn't get scheduled very often.

John P