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

[Jim Abernathy]

On 2/22/19 10:43 AM, Allen Edwards wrote:
>
>
> On Fri, Feb 22, 2019 at 3:37 AM James Abernathy <jfabernathy at gmail.com 
> <mailto: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 <mailto: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
>
>
I noticed your references were from Winegard.  They know antennas. I use 
theirs on my RV. My RV sits in the backyard and with the antenna up it's 
much lower than my Clearstream 4MAX.  It also receives stations 90 miles 
away. I know that is very fringe situation but my house stuff stops 
receiving at about 50 miles. Everything like trees, wind, rain come into 
play.

One interference that I've become aware of is LED light regulators.  The 
RV industry use cheap LED pancake lights mounted to the ceiling and when 
they are one it wipes out any but the strongest signals. Nothing worse 
for noise than a square wave regulator.

Jim A

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