[mythtv-users] ATSC Unwatchable

Keith Wait kwait at alumni.rice.edu
Thu Sep 6 16:58:52 UTC 2012


> You should double check this.  The SNR field shown in azap is in 0.1
> dB increments, so 0xff is 25.5 dB (which is a marginal signal).  In
> other words, you'll get lots of errors.  Try a better antenna, or
> temporarily move the computer to a location where it can get better
> signal conditions.
>
> At this juncture all data points to "crappy signal conditions" rather
> than anything wrong with the device or the software stack.
>
> Devin
>
> --
> Devin J. Heitmueller - Kernel Labs
> http://www.kernellabs.com
>

I did some more testing and you are correct; it is possible for me to
get signal values above 0xff.  I've gotten at most up to 1e0.  So yes,
I believe that what the linux PC is being fed is a lousy signal.

However, I don't agree with you that 'At this juncture all data points
to "crappy signal conditions".'  If that were the case, why (as
originally noted) does plugging the antenna directly into the TV next
to the PC (TV, PC, antenna all unmoved) give me clear picture?  And
why does the card in a windows PC located in roughly the same place in
the house work just as well as the TV?

Is there anything other than azap I can use to get a second opinion on
signal strength?  Is it possible the frequency table isn't the same as
is used in my two non-linux PC cases?  Are there any modprobe options
I can use to try and mitigate this problem?  Are there other questions
I should be asking but am not?  Sorry for the hysterics, but the SO is
out of patience.

Thanks again for your time.

Cheers,
kw

PS (Apologies if I break the thread... I'm receiving digests and am
not sure that I am replying correctly)


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