[mythtv-users] Hauppauge WinTV-quadHD TV Tuner Card 1609 and Pixelation

Fri Feb 22 15:43:25 UTC 2019

On Fri, Feb 22, 2019 at 3:37 AM James Abernathy <jfabernathy at gmail.com>
wrote:

>
> On 2/17/19 6:07 PM, James Abernathy wrote:
>
>
>
> On Sun, Feb 17, 2019, 5:57 PM Devin Heitmueller <
> dheitmueller at kernellabs.com wrote:
>
>> > You mentioned the HVR-2250.  I threw that card away because it could
>> not receive my local PBS station. my HDHR Connect and Quatro can receive
>> that station at ~50%.  My new WinTV Quad PCIe receives that station at 83%.
>>
>> I would encourage you to be very careful throwing around these numbers
>> as they are not an apples-to-apples comparison.  Each demodulator chip
>> exposes it's SNR and signal level in a different format, so the scales
>> are largely arbitrary (and each of the three products you mentioned
>> have different demodulator chips).  Knowing that 50% is worse than 80%
>> is useful for a particular card, but don't think 80% on one product is
>> the same as 80% on a different product if they have different
>> demodulator chips.
>>
>> I'm not doubting the empirical results you've observed (i.e. that
>> newer devices are performing better than your older generation
>> products) - just the comparison of the actual numbers.
>>
>> (speaking as someone who has worked on various ATSC demodulator
>> drivers in the Linux kernel).
>>
>> Devin
>>
>> ==
>> Devin J. Heitmueller - Kernel Labs
>> http://www.kernellabs.com
>> ___________________________________
>>
>
> I would not disagree with you.  My point is with my antenna setup the
> HVR2250 could not scan the PBS station.  The HDHR Quatro could receive the
> station with occasional break ups. The WinTV is rock solid.
>
> Jim A
>
> I had a situation with my reception recently that made me do a revamp of
> my antenna situation. I had 2 antennas pointing in different directions and
> combined before making the long run from the attic to the splitter in the
> data distribution box. My previous setup was for use with HDHR tuners.
>
> Now with the WinTV QuadHD PCIe card I removed the weaker of the two
> antennas and the combiner. The main antenna is a Clearstream 4MAX without a
> distribution amplifier.  I set the antenna 45 degrees off of both main
> signal sources, about half-way between them. I used the HDHR signal
> strength to peak the signal, but when I scanned with mythtv-setup I had
> achieved 91% on the weak PBS station 30 miles away and 100% on all other
> channels.
>
> I know these signal values don't mean much except 100 is better than 90 is
> better than 50.
>
> What I conclude is the WinTV-QuadHD PCIe card is the best tuner I've
> tested. Much better than even the latest HDHR Quatro. A big issue for me is
> the network problems are completely removed. I had to completely isolate
> the HDHR tuners on one gigabit switch alone with the Mythtv backend to fix
> some of the issues, but that didn't fix them all.  So now the network is
> only for FE client activity which will have no impact on recording even if
> we are streaming multiple UHD 4K Prime or Netflix.
>
> Jim A
>

One of the advantages of independent antenna inputs on the HDHomeRun and
perhaps other tuners is that you can set one tuner to one antenna and
another tuner to the second antenna.  Then you set myth up so that the
channels you want are on the appropriate antenna.

Using a combiner to add two antennas creates a new antenna with new
directionality and gain characteristics. The signals from the two antennas
adds or subtracts depending on the patterns of the antennas. It is not a
good idea unless you really know what you are doing.  People sometimes take
identical antennas, space them vertically a specific distance and make a
higher gain antenna. Companies used to make antennas like this but you are
not going to get good results with a wide bandwidth antenna just combining
them. So not doing that was a good thing.

I would say that if your antennas are getting signals 45 degrees
"misaligned" that they are pretty low gain antennas. If you look at the
polar plots of what I would consider an acceptable HDTV antenna you will
see that if you are 45 degrees off you are going to lose at least half your
signal. http://www.winegard.com/kbase/uploads/HD7694P.pdf

On the other hand, I looked up the Amazon Recommended antenna and there are
just no specifications that I could find.  I did notice a long "50 mile
range" and "multi directional".  Long range and multi directional are
mutually exclusive terms so what is the performance?  Who knows.  Marketing
hype. Antennas get gain the same way a telescope allows you to see distant
objects. You just don't get a wide field of view and close up detail at the
same time.  It is just physics.

I would not buy an antenna that had a 50 mile range and was multi
directional any more than I would send money to the Nigerian Prince who
told me he would give me five million dollars for helping him move his
fortune into this my bank account.

I did some more looking and found this probably old document. I think it is
old but still useful.
http://www.winegard.com/kbase/uploads/WC-939%20OTA%20Product%20Cat.pdf

Just looking at a couple of antennas I see that a smaller one has 4.5dB of
gain and 61 degrees of beamwidth.  A better one has 12dB of gain and 40
degrees of beamwidth.

My point on antennas is that if you get a narrow beamwidth it will help
eliminate multipath reflections and give you a stronger signal at the same
time. The trend seems to be to dumb down antennas, make them easy to set up
and put amplifiers in them. Half the market doesn't even know that you can
get TV off the air so this might be a good way to go but it is a bit
frustrating to someone like me. I still have a full range huge antenna on
my roof.  Actually I have three of them as when HDTV first came out signals
came from three directions. Now all the stations we watch are more or less
in the same direction so two just sit there disconnected.

As a note. Where I am there are stations on channel 7 and 12 and I see they
will be reassigned to 12 and 13 next year.  These stations are called 7 and
11 but I am talking about where the RF energy is. That still means that I
could buy a "HDTV" antenna that might have negative gain for these
stations. Antennas are important and specifications are very difficult to
find as far as I have been able to see.

Good luck.

Allen

Allen
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