[linux-dvb] [PATCH] Add pll information for some NXT2002 and NXT2004 based cards

CityK CityK at rogers.com
Tue Oct 25 20:44:15 CEST 2005


Kirk Lapray wrote:

> According to the information I found it said 57MHz.
>
> Here is what I found:
> http://www.business-sites.philips.com/assets/Downloadablefile//TUV1236-1747.pdf
>
Indeed.  I checked the three RF Solutions Product Overviews I have (Nov 
03, Feb 04, Jan 05) and they state the same.  Nonetheless, I strongly 
think this may be an error that has been propagated in the Philips 
PDFs.  Specifically, if it is truly 57MHz, then the tuner is cutting out 
channel 02 on both the low band VHF and cable spectrum.  See:
http://www.qsl.net/atn/library/Broadcast_freqs.htm
http://www.jneuhaus.com/fccindex/cablech.html

(This is actually kind of funny considering, not so long ago, I thought 
the frequencies for the Nxt2002 driver may have been incorrectly 
programmed :)  )

> The tuner and NXT2004 demodulator chip are integrated into the 
> TUV1236D Network Interface Module.  I don't think there is a specific 
> Philips tuner used.  From what I understand the NXT2004 also 
> demodulates the analog signal.  

No, I'm pretty sure the Nxt2004 is incapable of analog demodulation. 
You'll notice its absence from the spec overview:
http://www.ati.com/products/nxt2004/features.html

As for the tuner and analog ICs, you can see what I believe to be them 
in the following photo: http://www.anandtech.com/showdoc.aspx?i=2089&p=3 
. Click on the photo for a close up (Warning very big picture!).  In the 
close up photo, you can make out some of the model number on the topmost 
chip (tuner?) but the middle IC gets washed out.  I can, however, 
distinctly observe the shadow of the Philips shield emblem on this 
middle IC.  I believe this is the analog demodulator.

Lastly, I think that http://www.ati.com/companyinfo/press/2003/4596.html 
offers further proof.  Examples:
- "State of the art digital and analog cable reception is realized by 
the combination of Philips RF technology and ATI's NXT2004"
- "The TUV1236 contains the same ATI technology and adds a NTSC demodulator"
- "All modules incorporate Philips' proprietary RF AGC (automatic gain 
control) detector to ensure excellent performance, even in large signal 
conditions where most tuners suffer from overload"

-  Cheers, CK



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