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Samsung Owners: DTV tuner abnormal PSIP data quality?

  • Never have any problems

    Votes: 44 42.3%
  • Occasional problems with certain stations

    Votes: 30 28.8%
  • Frequent problems with certain stations

    Votes: 29 27.9%
  • Frequent problems with all stations

    Votes: 1 1.0%

  • Total voters
    104
861 - 880 of 888 Posts

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Samsung ATSC tuners

I have two Samsung hdtvs:
an LNT5265FX/XAA from 2007 and an LN32D405EDXZA from 2012

In pursuing weak signals in my area, I have tried various antennas, attenuators ,pre-amps and a variable UHF trap to make things work.

My greatest success comes when I bypass the Samsung HDTV tuners completely and use a ZAT 502 HD box. The difference is dramatic- "weak signal" ( no picture) from Samsung tuner to 100% QUALITY from the ZAT 502 HD. It also outperforms the Hauppage 950Q USB tuner.

What is it about the ZAT 502 HD that makes it perform so much better than the internal Samsung tuners in my situation?
 

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Your persistence in finding the best solution for your reception problem, like adding the Winegard UT-2700 that tamed your very strong UHF signals.
 

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Unfortunately, there is no comparative listing of tuner performance by brand or even within the same brand. You had to find out the hard way by trial-and-error, which is called the empirical approach.

The tuner in the ZAT502HD is the same as in the Apex DT502. Forum member holl_ands has a list of CECBs that shows tuners used:
http://imageevent.com/holl_ands/files/ota
scroll down to and click on
FILE 7 CECB Feature List - mod 26Mar2010.xls
http://imageevent.com/holl_ands/files/ota?p=6&n=1&m=-1&c=3&l=0&w=1&s=0&z=4
choose Excel or pdf
scroll down to Apex DT502 which shows the tuner DTVS220PH2610
That is a typo; it should be SAMSUNG DTVS22DPH261D. The type face that they used on the tuner label makes the Ds and 0s look alike.

The way I use to compare tuners is to feed two tuners from a 2-way splitter with a variable attenuator before the splitter. I then increase the attenuation to see which tuner drops the signal last to find the winner. In this setup I compared the Apex DT502 tuners with the SONY KDL22L5000 tuner:



It doesn't work to disconnect the coax from one tuner and then connect it to the other, because OTA signals are constantly changing, especially weak 2Edge signals.
 

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I purchased a new LG TV in November 2014. CBC Toronto is the only channel which does not display info. I thought it was a CBC problem, until I did a few service calls. All TV's I've seen this year seem to work fine on CBC, including my Sony TV in the basement.
I will have to keep an eye out for other LG TV's.

Does anyone know, or understand, why LG TV's are having problems?
 

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^^^ LG Firmware. CBC uses an ATSC table called CVCT. It's an optional table and strictly speaking, legal ATSC although adds no value as far as I can tell. It appears some firmware (including the one LG uses) can't handle it. In the Toronto area, CBC (both English and French) are the only ones that include it.

FWIW, CBC uses a PSIP generator from Triveni. When I asked them about it years ago, they told me me they did no special setup and this was "out of the box" so to speak. WUTV (Fox 29 Buffalo) also uses Triveni and don't include CVCT (maybe they turned it off?). I know some of those DTV converter boxes also have trouble with WUTV for other Triveni-related issues.
 

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Thank you for that detailed explanation.

The odd thing is, the info does pop up on my TV very intermittently, but only for a couple of seconds at a time.
 

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Yes...all Native Resolution 1280x720 HDTV's (many are actually 1366x768p) will also play a 1080p from a BD Player.

Internally, a 720p (or 768p) HDTV performs a Down-Resolution and De-Interleave process on the 1080i video signal...with the better 720p sets calculating EXTRAPOLATED video frames in between each pair of 1080i frames (each of two frames contains every OTHER scan line), which is reflected in whether they claim a screen refresh rate of 60, 120, 240 (or higher) refresh rate. The BEST De-Interleavers employ MOTION ADAPTIVE EXTRAPOLATION....and in many OLDER LCD/DLP's they took a short cut and simply THREW AWAY every other 1080i frame, resulting in a much LOWER resolution of 540x1080p:
https://en.wikipedia.org/wiki/Television_standards_conversion#Adaptive_motion_interpolation
https://en.wikipedia.org/wiki/Deinterlacing
https://en.wikipedia.org/wiki/Display_motion_blur
 

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Can 2 different channels occupy the same real and virtual channels?

I'm pretty new to DTV and I've got something going on w/my TV that I don't understand. I live near Ottawa wherein the nearby CTV channel is CJOH-DT. If I click the favourite for it, the TV tunes 13.1 and the real channel is 13. The S-meter indicates a very strong signal, but my TV just tells me there's no broadcast. I push channel up, it switches to 13.1 and is still on real channel 13, but I get a picture. What's going on? Is there something I don't understand about DTV or is my TV just mental? (I've already done a firmware upgrade) I've noticed sometimes one of the American channels also gives no picture even when the signal is strong.
 

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Trying, maybe, but it still says 13.1. In the absence of any other replies, I guess it means that what the TV is ostensibly doing is impossible, and it's just flakey. I've noticed it demonstrating race conditions elsewhere. 'Worth remember it's a Sharp next time I'm shopping for a TV.
 

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Ultra: It may be an odd time to evaluate Ottawa CJOH 13 and your TV behaviour. IDK what happens but occasionally with this channel, everyone loses PSIP, the channel code-name changes slightly, and some receivers either can't pick up the channel any more or have difficulties. It's something that periodically seems to sometimes happen for days or weeks until it gets corrected somehow - and it is happening currently. I don't understand it well but have seen plenty of mentions regarding in the Ottawa and regional forum threads.
 

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Thanks for the insight. What's PSIP?
Perhaps my upstairs TV is more robust (it's certainly newer) but I haven't at the same problem on that set. Also, I had a similar problem w/the American channels. In came down to no picture, but a strong signal for about a week. I don't remember if it was 18.x or 28.x. 'Know anything about that?
 
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