[linux-dvb] Re: FusionHDTV3 Gold-T / Thomson DDT 7610 - analog NTSC tuner dead - digital ATSC still works

Michael Krufky mkrufky at m1k.net
Tue Nov 29 19:12:25 CET 2005

Michael Krufky wrote:

> My card was working fine for a good long time, but ever since about 2 
> months ago, the analog tuner no longer works.  ONLY the ATSC digital 
> tuner is working.  The tuner does NOT include a tda9887, AFAIK, and I 
> have also tested in windows.  Regardless of whether I am using Linux 
> or Windows, I can only view an ATSC digital stream, NTSC analog no 
> longer works at all.  Both used to work in both OS's.
> AFAIK, this is a physical hardware problem, and has nothing to do with 
> any bad coding.  For the life of me, I cannot figure out what went wrong.
> Maybe someone might be able to tell us what factors can burn out a 
> hybrid tuner's analog capabilities, and leave digital tuning 
> capabilities intact.
> Maybe the Thomson DDT 761x tuners are faulty?

CityK wrote:

> Michael Krufky wrote:
>> CityK wrote:
>>> a) Is there any chance that your loss of analog might be in any way 
>>> related to this: 
>>> http://www.linuxtv.org/pipermail/linux-dvb/2005-July/003536.html ?
>>> I'm not sure what Mac eventually introduced, or whether or not it 
>>> would possibly have affected your card.
>> No... Mac was talking about ways to switch RF inputs on the 
>> FusionHDTV3 Gold-Q model, which used a microtune tuner with two RF 
>> inputs.  My tuner only has one input, and it has always worked with 
>> Mac's callback implementation.  Kirk has used a similar method to 
>> implement this in nxt200x.
> Yep, that is very clear.  I'm just throwing out ideas ... Recall that 
> you wrote:
> / I use the same rf input to use
> />/ OTA VSB as I use for cable QAM.  I think that if you
> />/ altered the frontend like this, it could break the
> />/ usability on my board./
> I was just wondering if there was (a long shot) connection between 
> your analog going dead and this.....I was thinking along the lines of 
> a bit becoming "stuck" ... which reminds me, was there not discussion 
> about something being stuck, and requiring a switch into a Windows 
> environment to unstick the bit, early in the development of the Fusion 
> drivers?

I appreciate the ideas, but unfortunately the rf selection isn't the 
culprit here - Mac implemented this by using a callback that IS defined 
for the Gold-Q card, but NOT defined for the Gold-T board.... BTW, if 
there are any other boards that use lgdt330[2,3] , they can also use 
this callback function to change RF inputs.

..and about that "stuck" bit, being fixed only by a cold boot -- That 
was during development of the FusionHDTV5 Gold driver... completely 
different animal, using LG DT3303 (instead of DT3302), and using 
LG-TDVS-H062F, containing TUA6034 tuner (and tda9887), rather than the 
Thomson DDT 7611 / [Temic/Microtune] 4042 tuner.

IIRC, we worked that out in the end by programming the tda9887 chip.

>>> b) What analog demodulator is used in the Fusion 3s 
>>> (18ac:d800,18ac:d810,18ac:d820) ?  What did Mac use? (he didn't 
>>> mention: 
>>> http://www.linuxtv.org/mailinglists/linux-dvb/2004/08-2004/msg00074.html) 
>> Wow... Very interesting thread, although unrelated to this topic.  
> I hummed and hawed about whether or not to start a new topic ... but 
> as this particular discussion (dead analog in Fusion 3) was introduced 
> in this thread, I thought I would continue it here....Nonetheless, 
> thank you for adjusting the subject heading to more accurately reflect 
> the topic.

You did nothing wrong... I was only trying to say that I didnt see the 
relevance -- Thanks for explaining, now I see what you are saying.  I 
was by NO MEANS criticising you for digressing from the thread topic.  
Sorry for the misunderstanding.

>> Wow... Very interesting thread, although unrelated to this topic. In 
>> that thread, Mac was discussing DVB API changes needed to support the 
>> American standards.  
> Yes, I know what Mac was discussing.  Perhaps I didn't articulate my 
> points to question b) very well.  Anyways, what I was trying to convey 
> was:
> a) That was the first post Mac made regarding the Fusion 3, in 
> particular, its analog side, and he didn't mention what analog 
> demodulator it was using....In fact, I don't recall him ever 
> mentioning what IC is employed.
> b) Discovering what analog demodulation IC is used might greatly aid 
> in the discovery of why the analog side of your card is no longer 
> functioning...and whether or not it can be restored (hopefully).

I agree.  Thanks for explaining this, I had missed your point, 
originally.  How can I find out what IC is employed?  (I have a feeling 
that you're going to tell me to write to DViCO -- They always reply to 
my mails, but they take approx 2 months each time :-(  )

I'll take another look at the Thomson DDT 761x datasheet ... maybe 
there's some info about it there.

/me hopes!

>> Anyhow,
>> 18ac:d800 FusionHDTV3 Gold     temic4042 + lgdt3302
>> 18ac:d810 FusionHDTV3 Gold-Q   temic4042 + lgdt3302
>> 18ac:d820 FusionHDTV3 Gold-T   thomson7611 + lgdt3302
> Yes, I know all that (as you very well should know :-)  ) , but it 
> still doesn't answer part (b) --> i.e. what's the analog demod.?

inquiring minds want to know

>> Please note: the 18ac:d800 subsystem id is not yet included in 
>> cx88-cards.c, although card=17 will probably work.  If somebody can 
>> confirm it, then I would be happy to add it in.
> Cool.  As you already know, I  picked this last part of the discussion 
> up on the DVB list.  Perhaps Taylor or someone else will let us know. 

Yes...  I also have information about FusionHDTV II ...  If anybody out 
there has one, please let me know, and I'll send you a patch to test.


Michael Krufky

More information about the linux-dvb mailing list