[mythtv-users] Hauppauge WinTV-quadHD TV Tuner Card 1609 and Pixelation
allen.p.edwards at gmail.com
Fri Feb 22 16:34:20 UTC 2019
On Fri, Feb 22, 2019 at 8:25 AM Jim Abernathy <jfabernathy at gmail.com> wrote:
> 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>
>> 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 J. Heitmueller - Kernel Labs
>> 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
>> 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.
> 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.
> 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
> 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
I am a HAM and there are no light dimmers in my house for the same reason.
I was not aware of the LED issue as I have been off the air for a number of
hears. Your RV antenna in all likelihood has an amplifier built in, mine
In the old days, if you didn't have a good antenna setup you got ghosts.
You needed a good antenna, a preamp, and good lead wire to get a good
signal. Now you get a good signal regardless of what you have, until you
don't like when the wind blows. I don't think people appreciate the
importance of the antenna. From the sales literature and the Amazon review
comments it looks like the customer base is significantly dumbed down.
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